Final Technical Report Group #1 Thomas Chaisson, Joelle Cingel, …thomaschaissonportfolio.weebly.com/uploads/7/9/1/6/... · 2018. 9. 4. · Running head: FINAL TECHNICAL REPORT GROUP

Running head: FINAL TECHNICAL REPORT GROUP 1 1

Final Technical Report

Group #1

Thomas Chaisson, Joelle Cingel, Oana Ciobanu, Connor Fenn,

John Fitzell, Anna Kaplan, Jack Ravekes

Severna Park High School

May 9, 2016

FINAL TECHNICAL REPORT GROUP 1 2

Table of Contents

Abstract…………………………………………………………………………………………....4

Problem Statement and Statement of Purpose…………………………………………………….5

Market Research…………………………………………………………………………………..5

Armor Ball………………………………………………………………………………...5

Hexprotect………………………………………………………………………………...6

Shade Balls………………………………………………………………………………..7

Water Savr………………………………………………………………………………...8

Aquatain…………………………………………………………………………………..9

E-Vap-Cap……………………………………………………………………………….10

Justification………………………………………………………………………………………11

Design Criteria…………………………………………………………………………………...13

The Design: Hexaflex……………………………………………………………………………17

Explanation of Prototype………………………………………………………………………...20

Test Procedures and Results……………………………………………………………………..22

Cost Analysis…………………………………………………………………………….22

Distribution………………………………………………………………………………25

Evaporation (Version 1)………………………………………………………………….26

Evaporation (Version 2)………………………………………………………………….29

Material…………………………………………………………………………………..31

Rainfall…………………………………………………………………………………...35

Stress……………………………………………………………………………………..40

Waves…………………………………………………………………………………….42


Wind (Fan)……………………………………………………………………………….44

Wind Resistance (Version 1)…………………………………………………………….47

Wind Resistance (Version 2)…………………………………………………………….49

Design Refinements/Future Improvements……………………………………………………...52

References………………………………………………………………………………………..53

Appendix A………………………………………………………………………………………58

Appendix B………………………………………………………………………………………62

Appendix C………………………………………………………………………………………63

Appendix D………………………………………………………………………………………66

Appendix E………………………………………………………………………………………69

Appendix F……………………………………………………………………………………….70

Appendix G………………………………………………………………………………………72

Appendix H………………………………………………………………………………………73

Appendix I……………………………………………………………………………………….77

Appendix J……………………………………………………………………………………….79

Appendix K………………………………………………………………………………………84

Appendix L………………………………………………………………………………………85


Abstract

The purpose of this paper is to detail the yearlong process of creating a product that reduces

evaporation in agricultural reservoirs the Southwestern United States. With the current drought,

states such as California and Arizona have been subject to extreme water loss, which has heavily

impacted the agricultural business, a primary economic source in these states. The product,

Hexaflex, is a floating cover comprised of many floating hexagonal tiles made of HDPE. The

shape provides maximum surface area coverage and HDPE is a highly durable and inexpensive

material. Tests were conducted which proved that Hexaflex reduces evaporation by 85-90%,

which is expected to increase when piloted. Hexaflex is also wind resistant, as each tile is filled

approximately halfway with water to ensure appropriate floating depth and that tiles do not blow

away. When exposed to wind or water level changed, the tiles will ride up on one another due to

their filleted sides and 17° chamfer angle.

Keywords: Evaporation, HDPE, Hexaflex


Problem Statement and Statement of Purpose

Problem Statement: Water levels of reservoirs between 2011 and 2015, decreased by an

average of 3.29 feet annually due to evaporation. Reservoirs in this region experience annual

temperatures with an average low of 66.6 °F and an average high of 92.5 °F at an average

humidity of 57.7%. The combination of high temperatures and low humidity is the main cause of

evaporation.

Statement of Purpose: Reduce the amount of water lost from reservoirs due to evaporation each

year.

Market Research

Armor Ball (http://paradisenw.com/armor_ball_cover.php)

Pros: 90% evaporation reduction. Prevents birds from using the water. 25 year life

expectancy. Easy installation. Made of recycled High Density Polyethylene (HDPE).

Rise and restack when water levels fluctuate. Reduces odor

Cons: Aeration would need to be installed beneath the armor balls to maintain life. Poor

wind resistance, (inferred) high initial cost.

Summary: The Armor Ball’s material sets a precedent for what a solution should

possibly be made of if a physical solution is pursued. It provides insight into the

durability and weight that would follow for such a solution. Physical solutions will also

http://paradisenw.com/armor_ball_cover.php


necessitate the acknowledgement of environmental effects, and that they not be a priority

in applications.

Hexprotect (http://www.awtti.com/hexprotect_cover.php)

Pros: 95% evaporation reduction. Prevents birds from using the water. Prohibits the

growth of algae. Requires little maintenance. Easy installation. Wind resistant up to 75

mph.

Cons: Aeration would need to be installed to preserve life forms. Ballast increases weight

by 260%, making it weigh more for shipping. Weighs four times as much as Armor Ball.

Summary: Hexprotect demonstrates high wind resistance and durability due to its ability

to interlock. The tiles form a cover over the liquid surface, preventing growth in the

water. Hexprotect gives insight into ways to make a physical solution durable and keep

water free of algae and bacteria.

http://www.awtti.com/hexprotect_cover.php


Shade Balls (http://www.shade-balls.com/Water-Reservoir-Balls-Floating-Ball-Covers-Shade-

Balls-s/100.htm)

Pros: Deters waterfowl, and prevents algae growth. Able to adjust shape to fit nearly any

surface shape (does not need to be custom-made). Approximately 75% evaporation

reduction, long lifespan (10 years).

Cons: Costs approximately $15,680 per acre, or approximately $1,568 per acre per year.

Encourages non-photosynthetic anaerobic bacterial growth (aeration is required). Poor

wind resistance. Lifespan not comparable to other similar solutions.

Summary: Shade Balls are not durable compared to other products, making it a baseline

for the standards of the product. They are also made of HDPE, showing that this is a

popular material that can be used for physical solutions. The physical solutions above are

well suited to being long term solutions, as they have a high initial cost but little to no

maintenance cost.

http://www.shade-balls.com/Water-Reservoir-Balls-Floating-Ball-Covers-Shade-Balls-s/100.htm

http://www.shade-balls.com/Water-Reservoir-Balls-Floating-Ball-Covers-Shade-Balls-s/100.htm


WaterSavr (http://www.flexiblesolutions.com/products/watersavr/)

Pros: Reduces open water evaporation by up to 45%, has no adverse effects on

environment (has NSF certification), can be easily applied (manual or automatic), cost is

approximately $59 per acre, or approx. $5,900 per acre per year. Due to need to reapply

to maintain effectiveness, treatment can be immediately discontinued (in the case of

market fluctuations, etc.). Has no effects on vertebrates and invertebrates.

Cons: Degrades after three to four days, meaning it needs to be constantly applied,

though in reduced quantities. Does not perform favorably (performance reduction of

approx 50%) in windy conditions (average wind speed > 15mph). The applier needs to

wear a dust mask, safety glasses, and gloves while applying. The empty container,

without the chemical solution, is 125 pounds in weight.

http://www.flexiblesolutions.com/products/watersavr/


Summary: Fatty alcohol monolayers are a flexible solution which are fairly inexpensive

in the short run and easily maintained. Solution is not durable, but is suited for short term

or intermittent use.

Aquatain (http://www.aquatain.com/WaterGuard.html)

Pros: Reduces open water evaporation by up to 50%, few adverse effects on

environment, easily applied (manual or automatic), initial cost is approximately $360 per

acre, or approx. $5340 per acre per year. Treatment can be discontinued (in the case of

market fluctuations, etc.). Interferes with insect species dependent upon a water surface

(mosquitos). Performs well in wind.

Cons: Some adverse environmental effects; interferes with insect species dependent upon

a water surface (not just pests). Must be maintained through reapplication, though in

reduced quantities. Is not biodegradable (degradation catalyzed by clay, absorbed by

treatment plants).

Summary: A polydimethylsiloxane monolayer solution represents a longer-term solution

than fatty alcohols. Lasts longer per application, is more durable, and is slightly more

effective, although it is less flexible than fatty alcohols. This chemical solution and the

one above are better suited for intermittent application (useful in the case of market

http://www.aquatain.com/WaterGuard.html


volatility for example), or as a stop-gap, as they do not require a significant investment

for initial installation. This is because of their low initial cost and relatively high cost of

maintenance.

E-VapCap (http://www.evaporationcontrol.com.au/aboutecsproduct.htm)

Pros: Effectively reduces evaporation by 90%, reduces salt build up, prevents algae

growth, life span of 10-20 years depending on thickness.

Cons: Once covered, the reservoir cannot take in more water from rainfall, no

photosynthetic life forms can grow, can only cover small sized reservoirs, must be

custom manufactured, difficult to install, less resistant to UV.

Summary: Floating cover made of a multi-layered, polyethylene membrane 540

microns in thickness, up to 850 microns. Outer cover is white to reflect sunlight

underside is black to eliminate transmission of light to the water. Environmentally

neutral, material fairly resistant to environment. Shows that polyethylene is a viable,

durable material. Economics similar to other physical solutions, however, a single failure

(splitting of the cover) can cause a significant loss in effectiveness and usability.

http://www.evaporationcontrol.com.au/aboutecsproduct.htm


Justification

The states of the southwestern US; California, Nevada, Arizona, and New Mexico, are

experiencing severe water loss from reservoirs due to evaporation. This water loss exasperates

the current drought, which began in 2012. Addressing this issue occurs on a county level, as

most reservoirs are owned and managed by these counties. The current solutions do not directly

address evaporation but rather seek to mitigate its effects. Water conservation regulations and

incentives, groundwater banking, and lastly, surface treatments such as the Shade Balls used by

Los Angeles are the primary methods through which supply shortages are addressed.

Firstly, the Los Angeles reservoir has implemented Shade Balls, whose primary task is to

prevent the formation of harmful chemicals. They have also reduced evaporation (although this

is an unintended advantage), and require little maintenance, and require no significant

infrastructure. However, surface treatments thus far have not proven to be a cost effective means

of evaporation reduction.

Other county areas, such as San Diego, Santa Barbara, and Carson City, have dealt with

the issue of water loss by reducing water use in general and encouraging citizens to partake in

water conservation efforts. These efforts have been met with overwhelming support and allow

the county to use water only as needed without making significant changes to behavior or

infrastructure. In California, the state asked citizens to reduce water use by 25%, and this goal

was surpassed with a final reduction of more than 33%. However, these measures, while making

an impact, are still not enough. The majority of respondents said that their organizations/agencies

are still drawing down reserves at unsustainable rates, in some cases even exceeding maximum

safe yield.


Groundwater banking is the most common method of addressing the issue of water loss.

Of the eight people contacted directly involved in reservoir operations, all responded that

groundwater banking is implemented to some degree in their system, with three stating that

groundwater banking is their primary method of water storage. Because water stored in this way

is not exposed to air, these reservoirs do not experience evaporation, and serve as a form of

viable long term storage. However, groundwater banking requires intensive maintenance, and

cannot be implemented at low elevations due to leaching and pollution risks. Additionally, this

solution demands close, complex management and therefore is the most costly.

Each of these solutions have their own set of advantages and shortcomings. Together,

they form a robust water conservation strategy, but there is a gap in this system, and that gap lies

with surface treatments. All participants emphasized that groundwater banking is one of the best

methods for storing water reserves, but only surplus water can be diverted to these “banks”.

Because of the drought of 1988-1992, total water reserves are still on average 20% below

nominal, due in part to a constant stream of water being lost to evaporation over the 20 years

between droughts. It is necessary to directly address evaporation from reservoirs. Although

surface treatments directly address the problem of evaporation, none so far have proven to be

cost effective. By directly contacting officials related to the operation of reservoirs and the

distribution of water resources, it has been determined that the ideal solution must be cost

effective, raise awareness of the importance of water conservation, and be easy to implement and

maintain.


Design Criteria

1. Performance/Operating Environment: The product must reduce the evaporation from

Agricultural Water Reservoirs (AWRs) to less than the current 3.29 feet per year (Hudson,

2015; New Mexico Of Office of the State Engineer, n.d.; “Texas reservoirs,” n.d.; Texas

Water Development Board, n.d.; Western Regional Climate Center, n.d.). The product must

be able to withstand maximum winds of 120 miles per hour (Feather, 2007). The maximum

air temperature in California is 120°F (National Temperature, n.d.) so the product materials

operating temperature must be at least 140°F (“Operating temperature,” n.d.) without

suffering a performance decrease of greater than 50% in either extreme.

a. operating environment. Air temperatures average between 66.6 and 92.5 °F

(“Temperature-precipitation,” n.d.; The Weather Channel, n.d.; “Sierra County

weather,” n.d.), and humidity averages 57.7% (“Annual Average Humidity,” n.d.;

“Sierra County weather,” n.d.). The specific Total Dissolved Solids for salt (sTDSs)

does not exceed 2000 mg/L in operational agricultural reservoirs (R. Ayers, 1989).

Average wind speed in the southwestern United States is 15.77 mph (USA.com,

2012). The product must be able to withstand solar UV radiation for at least 12 hours

a day at a UV index of 13 over the product’s service life (“Weather and climate: Los

Angeles,” n.d.; Climate Prediction Center, n.d.; “How the UV index scale works,”

n.d.). The average surface area is 45,513 acres (Hudson, 2015; New Mexico Of

Office of the State Engineer, n.d.; “Texas reservoirs,” n.d.; Texas Water Development

Board, n.d.). Additionally, the water in AWRs is held at a pH between 5.5 and 6.5, so

the product must be able to operate in mildly acidic environments (Smart Fertilizer,

n.d.).


2. Customer Needs/Target Cost: The customer requires a product that reduces the amount of

water evaporating from agricultural water reservoirs (AWRs) in a cost effective manner (see

target cost). The average evaporation from AWRs (see performance) is 3.29 feet per year

(Bloomberg, 2014; “Farm ponds for irrigation,” n.d.; Hudson, 2015; New Mexico Of Office

of the State Engineer, n.d.; Texas Water Development Board, n.d.; Western Regional Climate

Center, n.d).

a. target cost. Given an average market value of $1,100 (Bloomberg, 2014) per acre

foot of water and an average evaporation of 3.29 feet per year (Hudson, 2015; New

Mexico Of Office of the State Engineer, n.d.; “Texas reservoirs,” n.d.; Texas Water

Development Board, n.d.; Western Regional Climate Center, n.d.), the solution must

cost no more than $3,619 per acre per year (3.29 feet * $1,100 per acre foot of water

= $3,619 per acre per year).

3. Durability and Maintenance/Service Life: The product will not require routine

maintenance. Previous solutions last 10-20 years with little to no maintenance (Shade Balls,

n.d.; AWTT, 2012; Evaporation Control Systems, 2006). There should not be any

replacement parts or maintenance plans necessary.

a. service life. The service life will be at least 10 years, as referenced to previous

products (Shade Balls, n.d.; AWTT, n.d.; Evaporation Control Systems, n.d.). At the

end of 10 years or more the customer must be able to collect and recycle the product

(see Ease of Use).

4. Material: The product must have a thermal expansion of less than 111.1x10-6 ℉-1

(“Thermal properties,” n.d.; “Lecture Notes,” n.d.; Martinez, 2015). It needs to be recyclable,

according to the Environmental Protection Agency standards for recyclables (EPA, n.d.). It


also must have a total water absorption of no more than 0.1% (“High density,” n.d.) over its

expected service life (“Water absorption,” n.d.). Additionally, the product must be able to

tolerate common chemicals used to reduce algae and microorganism growth (Wisconsin

Department of Natural Resources, 2012; R. Carlson n.d.; SpillTech, n.d.). The product must

also be able to tolerate the UV radiation over its service life (see Operating

Environment)(RTP Company, n.d.). Additionally, the water in AWRs is held at a pH

between 5.5 and 6.5, (see operating environment).

5. Product Life: The product life will depend on developing technologies. New

nanotechnologies, such as carbon nanotubes and nanoclays, are used to strengthen plastics as

well as introduce new properties into materials (“Chasing nanocomposites,” n.d.). Reliable

methods to infuse carbon nanotubes into materials are not yet practicable (“Carbon

nanotubes,” n.d.). The development of entirely new plastics, such as recyclable, self-healing

polymers, could have a major impact on the product (“IBM discovers,” n.d.).

6. Safety and Legal Issues/Global Environment: To avoid being a choking hazard to humans

and waterfowl, the product must be greater than 1.75 inches in diameter (Goldman, D, 2004).

The product must comply with the current Conditional Waiver of Waste Discharge

Requirements for Discharges from Irrigated Lands (Irrigated Lands Regulatory Program,

n.d.). The product must not release chemicals which are harmful to agricultural products,

specifically those in Table 1 of Ayers, R., 1989. The product must also not be flammable

according to the standards of Underwriters Laboratories (“Flammability testing & ratings for

plastics,” n.d.).

a. global environment. The product must not release compounds that are harmful to

crops or the ecology affected by runoff and leaching (Irrigated Lands Regulatory


Program, n.d.). The product must be recyclable according EPA recycling standards

(EPA, n.d.). The product must also prevent the growth of anaerobic bacteria in order

to mitigate possible crop infections; this is accomplished by surface area coverage

and through certain chemical solutions, the tolerance to which is discussed in

materials (SpillTech, n.d.).

7. Ease of Use and Installation:

a. installation. The product must have an installation rate of 10 acres per hour using 53

foot long semi-trucks. This calculation is based on the installation of 96 million Shade

Balls that are 4 inches in diameter over 175 acres. (Gebelhoff, R. 2015, August 14;

“Shade ball deployment,” n.d.; “YRC freight,” n.d.) The hourly rate of an installer

would be $15.00 (“Solar energy system,” n.d.) No equipment or special skills should

be necessary to install the product.

b. maintenance. It must also be unaffected by fluctuating water levels and still perform

at nominal capacity (AWTT, n.d.; Texas Reservoirs, n.d.; Farm Ponds for Irrigation,

n.d.). The product must not inhibit the use and distribution of chemical additives in

the reservoir (SpillTech, n.d.), specifically copper sulfate and chelated copper

(Extoxnet, 1994; Sanco Industries, 2011; Wisconsin Department of Natural

Resources, 2012), which prevent algal blooms.

c. removal and end of life. The consumer can remove the product by skimming the

surface of the water or by other purely mechanical methods. No chemical solutions or

specialized equipment will need to be purchased. The product will be made of plastic

that meets the recyclability resin codes (EPA, n.d.).


8. Size and Weight: The product must have a density less than that of water: 8.35 lbs per

gallon (Seaperch n.d.). The solution must be able to withstand wind speeds of up to 100 mph

(Feather, 2007). In such winds, the product must continue to cover the nominal surface area,

and must not suffer structural failure or deviate from a uniform surface density by more than

a factor of 2 (see performance). As points of reference, the Armor Ball has a diameter of 4

inches whereas the Hexprotect has a diameter of 8.7 inches from vertex to vertex (AWTT,

n.d.; AWTT, n.d.). As discussed in safety and legal issues, the product must be at least 1.75”

in diameter (Goldman, D, 2004).

9. Aesthetics: Existing products, such as the Shade Ball, the Hexprotect, and the Armor Ball,

prove that the product’s shape must allow it to shift and rearrange with fluctuating water

levels (Shade Balls, n.d.). A dark color will prevent light from reaching the water, so colors

like black will increase the service life of the product because it will not fade (McKinnon,

2015). Carbon black may be the optimal color (Sustainable Operation Excellence, n.d.). The

final shape of the product may focus on an angular design as farmers, being an individualistic

group, have a tendency to prefer hard-edged forms (Batra, R. n.d.).

The Design: Hexaflex

Shape

Hexaflex is a filleted, truncated hexagonal bipyramid. The hexagonal footprint allows

Hexaflex to tessellate (i.e. to become organized in a repeating pattern which has no empty

spaces) for efficient surface area coverage. The individual pieces cover surface of the water as a

floating cover. The pieces have a major diameter of 8.1” (see Appendix L, Optimization of Size).

This very efficient surface area coverage allows for the reduction of evaporation; as surface

coverage increases, evaporation decreases.


Hexaflex has a 17° chamfer angle for the purpose of self-distribution and installation.

This is the minimum angle at which Hexaflex cannot stack more than 1 unit high. This means

that, given this chamfer angle, Hexaflex will self-distribute, organizing itself into a one-unit thick

cover.

Hexaflex is hollow, and will be filled approximately halfway with water. Blow molding

is the manufacturing method that best supports this process, as the product would be blow

molded and then filled partway with water before being sealed. Less material is being used

because it is hollow, as plastic is only needed to coat the surface of the mold for the thin wall.

Given the fact there is a thin wall, Hexaflex must be able to withstand certain static and dynamic

loads. Given these loads (and a safety factor of 3), the necessary thickness was determined.

Hexaflex is filleted to reduce material needs, and to increase resistance to wind. The

fillets decrease the lift experienced by Hexaflex when high winds pass over the top half by

enhancing the overall aerodynamic profile.

Material

High Density Polyethylene (HDPE) was the best choice in material, as it is inexpensive

and is also the material of choice for products with similar necessary lifespans and environmental

exposure. HDPE has a lifespan that can be upwards of 100 years, but as rigorous testing was not

able to be completed, a conservative anticipated lifespan for Hexaflex is 15-20 years. Hexaflex

will also be exposed to extreme environments, so HDPE is resistant to a range of salinities, pHs,

high temperatures, and UV radiation. HDPE’s chemical resistance is a product of the plastic

itself, whereas its resistance to UV radiation is conferred by an additive, carbon black colorant.

HDPE also has a density less than water, allowing for it to float easily on the surface of the


water. In the event that an individual piece cracks, it would simply continue to float, making any

necessary cleanup relatively simple.

Conclusion

Hexaflex ultimately solved the problem, as it met all the previously stated design criteria.

Hexaflex self-distributes, making installation relatively easy and simple. This self-distribution

behavior also allows Hexaflex to maintain performance even after being exposed to weather

conditions that might otherwise decrease its effectiveness, such as winds, heavy rain, and falling

objects. The simple installation and self-distribution allows the Hexaflex to quickly and

effectively cover the surface of the water, thereby reducing evaporation. At scale, an individual

Hexaflex would cost $0.50 to manufacture, and after a 30% markup that includes transportation

and installation, it would cost $0.65 to the consumer.

Given the current price of water and its rate of growth with respect to overall inflation,

and the cost per unit area of Hexaflex coverage, it is predicted that Hexaflex with reach the

break-even point approximately 14.5 years after installation, and will generate a net gain of

approximately $60,000 per acre over its anticipated 20 year life-span.


Explanation of Prototype

Iterations

The design initially began with a hollow piece with a hexagonal footprint. Chamfers and

shell thickness were primarily arbitrary.

1. Hard Edged 15 degree chamfer

A. Proved out the concept; needed optimization for size and angle.


2. Hard Edged 17 degree chamfer

A. Optimized chamfer angle to 17 degrees (See Appendix B )

3. Rounded Sides

A. Alternative considered alongside the chamfer version. Not used because of the

higher lift force it produced during testing (See Appendix I, Data Collection and

Results)

4. Filleted 17 degree chamfer

A. Increased aerodynamics and wind resistance; optimized overall size to 8.1 inches

major diameter, and shell thickness to 0.03625 inches (See Appendix L,

Optimization of Size). This was the final iteration of the design.


3D Printing

Prototyping with molded parts would be impractical since molds cost roughly $300,000

apiece. All prototypes were instead 3D printed in Polylactic Acid (PLA) plastic. HDPE was not

an option as it does not work well with fused deposition manufacturing. Each production run

produced 10 models at 30% scale. 70 pieces were printed for tests involving multiple pieces. In

addition, several custom pieces cut in half for wind testing purposes were also created.

Test Procedures and Results

Cost Analysis

Purpose: To determine the optimal method of manufacturing of Hexaflex based on cost using

the following manufacturing processes:

● Blow Molding

● Rotational Molding

● Injection mold with ultrasonic welding

● Injection mold with hot plate welding

Materials:

● A working computer with internet access

● Access to email and phone communications

● Inventor drawings for each specified type of manufacturing (See Appendix A)

● Manufacturing companies to contact

1. Blow Molding

a. C.L. Smith

b. Exi-Plast

c. Stern Companies Inc.


2. Injection mold with ultrasonic welding

a. Cardinal Plastics

b. Bruin Manufacturing

3. Hot plate welding

a. Cardinal Plastics

4. Rotational molding

a. Rotomold

Pass or Fail Criteria:

pass. If one of the manufacturing companies provide a quote for $1.28 per unit or less,

then the test passes.

fail. If all of the manufacturing companies provide a quote for more than $1.28 per unit,

then the test fails.

Data:

Company Type of

Manufacturing

Cost Per Piece ($) Pass or Fail

C.L. Smith Blow molding ~1.00 Pass

Exi-Plast Blow molding 0.50 Pass

Stern Companies Inc. Blow molding 0.66 Pass

Cardinal Plastics

Injection mold with

ultrasonic welding

1.76 Fail


Bruin Manufacturing

Injection mold with

ultrasonic welding

1.86 Fail

Cardinal Plastics Hot plate welding 1.81 Fail

Rotomold Rotational molding 24.00 Fail

Results: Pass; 3 companies out of the 7 provided quotes of less than $1.28.

Discussion of Results: Only blow molding companies provided quotes that passed the cost test.

Research had to be completed to determine what methods of manufacturing should be considered

for the production of Hexaflex due to the importance of cost-effectiveness for this product.

While injection molding is a quick and effective method of manufacturing, the cost to mold

Hexaflex and then weld it together via hotplate or ultrasonic welding was expensive, with the

lowest price being $1.76. Rotational molding was eliminated from consideration after the receipt

of a quote. Manufacturing time is also unacceptably long. Blow molding is the least expensive

method for producing Hexaflex, as all the quotes provided by blow molding companies were

well under the cost limit.

Recommendations: This test is accurate, as each quote was provided by a professional

company. However, the prices will vary depending on the HDPE market price. Receiving more

quotes would reinforce the decision to choose blow molding as the manufacturing method, but

the consistency of prices was satisfactory for this test.

It would be ideal to make Hexaflex even less costly. Making Hexaflex smaller in size or thinner

would reduce the amount of material. However, decreasing the wall thickness would decrease


the load that Hexaflex could support and make the product more likely to fail under stress. The

loss of weight may also make it more vulnerable to blowing away in high winds.

Distribution

Purpose: Determine the minimal angle for self-spreading of Hexaflex.

Initial Conditions:

● Coefficient of static friction (HDPE on HDPE) is 0.29

● Mass of a Hexaflex is 118 grams

● Chamfer side angle is 15°

Materials:

● HDPE

● Calculator with basic trigonometric functions


pass. The component of force directed down the slanted surface is greater than the

resistive friction force.

fail. The component of force directed down the slanted surface is not greater than the

resistive friction force.

Procedures: See Appendix B

Safety Considerations: N/A

Results: Fail; There was a downward force parallel to the incline of 0.299 N and a friction force

of 0.324 N.

Discussion of Results: Hexaflex tested had a downward force parallel to the incline that was not

larger than the friction force. The design used had a chamfer side angle of, 15° so it failed the


test. The test is easily repeatable, as it is basic trigonometry and physics. As far as accuracy

goes, this test was conducted with the assumption of no outside energy added.

Recommendations: The calculations conducted predict a minimal angle of 16.6° in order for

Hexaflex to slide off each other effectively. It is recommended that at least a 17° angle is used

for added security and simplicity. Changes will be made to Hexaflex to reflect the 17° chamfer

angle.

Evaporation (Version 1)

Purpose: This test will measure the evaporation rate of water while Hexaflex is installed versus

the evaporation rate while Hexaflex is not installed.

Initial Conditions:

● The model reservoir is complete and marked along the side in centimeters (see Appendix

J, Evaporation (Version 1) Testing Environment)

● When Control Testing: use 51cm x 102cm x 13cm model reservoir

● When Treatment Testing: use 51cm x 51cm x 13cm model reservoir

● Model reservoir is on force plate such that it is in contact with no other supporting

surfaces

● Use a dehumidifier or humidifier to ensure that the environment has a constant humidity

of 15-18% during testing (see Appendix C, Humidity Instructions)

● Set the initial air temperature to 95°F using space heater

● Have 3.8.6.1 version of LoggerPro installed on the computer

Materials:

● 1 Model Reservoir (51cm x 102cm x 13cm)

● 1 Model Reservoir (51cm x 51cm x 13cm)


● Dehumidifier

● 80 Watt Heat Lamps (2)

● Ruler

● Digital Thermometer

● 80 Hexaflex (30% Scale)

● Logger Pro Relative Humidity Reader

● Logger Pro Force Plate

● Logger Pro 3.8.6.1 (http://www.vernier.com/products/software/lp/)


pass. When compared to the control, the volume of water lost to evaporation is reduced

by at least 75% while Hexaflex is installed.

fail. When compared to the control, the volume of water lost to evaporation is not

reduced by at least 75% while Hexaflex is installed.

Procedures:

1. Place control model reservoir on force plate.

2. Fill the reservoir with water to a depth of 6 cm (depth is approximate, small deviations

will not affect results.

3. Ensure that all sensors are operational; force plate and humidity sensors with Logger Pro,

and temperature sensor with independent readout (see Appendix C, Logger Pro

Instructions and Humidity Instructions).

4. Ready appliances for testing; heat lamps, space heater, and dehumidifier turned on.

5. Seal environmental enclosure, ensure that all initial conditions are met.

http://www.vernier.com/products/software/lp/


6. Use Logger Pro force plate to determine how much water is in the container (see

Appendix C, Logger Pro Instructions).

7. Begin collecting data on Logger Pro every 10 seconds. After 4320 minutes (3 days), stop

collecting data (see Appendix C, Logger Pro Instructions).

8. Divide the volume of the water lost while Hexaflex are installed by the difference

between the mass of the water in the treated reservoir and the untreated reservoir.

9. Repeat steps 1-8 for three control trials, and then three trials again for the treatment test.

Record data (see Appendix C, Results and Data Comparison). For the Treatment test,

place all Hexaflex prototypes in treatment reservoir and ensure even distribution (see

Appendix K, Pictures of Hexaflex (Properly Distributed)).

Safety Considerations:

● Do not touch the heat lamp while it is hot. Take the necessary precautions to avoid burns

and prolonged heat exposure.

● Read the directions for how to use a dehumidifier properly (see Appendix C, Humidity

Instructions).

● Make sure the lamp stays away from any flammable surfaces; use of a surge protector is

strongly recommended.

● Be cautious with water around electronic devices, especially those in the testing area.

● Wear closed-toed shoes and be careful while walking on wet and slippery surfaces.

● Safety goggles required.

Data: Water depth lost over time (cm/day). Treatment results will be compared to control

results.

Data Collection Graph or Sheet: (See Appendix C, Results and Data Comparison)


Results: Inconclusive.

Discussion of Results: The test was determined inconclusive because the first treatment trial

showed no substantial decrease in evaporation, so it was decided that the test was inaccurate and

that there was an issue with the environment or setup. It also took several days to run just one

trial, so repeating the test would be difficult in a reasonable about of time.

Recommendations: A new test will need to be written including a surface that heats a pan of

water to enable the test to be completed in a shorter amount of time and produce more accurate

results. This also allows the control and treatment trials to be conducted simultaneously, greatly

reducing the chance of interference by confounding variables.

Evaporation (Version 2)

Purpose: This test will measure the reduction of evaporation when a prototype treatment surface

is applied as it relates to no treatment.

Initial Conditions:

● The model reservoir is complete and marked along the side in centimeters (see Appendix

J, Evaporation Test (Version 2) Environment)

● 49.6cm x 29.5cm x 8.1cm metal pans as the reservoir

● Model reservoirs filled to 6.5 cm

● Water is at a temperature between 110° F and 120°F

● Thermometers attached to side of each pan for easy readout

Materials:

● 2 Model Reservoirs (49.6cm x 29.5cm x 8.1cm)

● Electric Stove (DSC 1260)

● Water (Anne Arundel County tap water)


● 60 Hexaflex

● Thermometer (Small, Alcohol)


pass. The volume of water lost to evaporation must be reduced by at least 80% while

Hexaflex is installed.

fail. Hexaflex does not reduce the evaporation rate by at least 80% while Hexaflex is

installed.

Procedure:

1. Meet initial conditions.

2. Place the model reservoirs on top of the stove.

3. For treatment model reservoir, install Hexaflex and ensure that they are evenly

distributed (See Appendix K, Pictures of Hexaflex (Properly Distributed)).

4. Every hour for 5 hours, measure and record the depth of water (See Appendix D, Results

and Data Comparison).

5. Determine loss ratio.

6. Repeat steps 1-5 for at least 3 control trials, and at least 3 treatment trials.


● Do not touch the stove while it is hot. Take the necessary precautions to avoid burns and

prolonged heat exposure.

● Avoid touching the water while it is hot.

● Do not wear loose fitting clothes.

● Be cautious with water around electronic devices. Make sure the testing environment is

distant from electronics or anything else that can be harmed by water.


● Wear closed-toed shoes and be careful while walking on wet and slippery surfaces.


Data: Water depth lost over time (cm/hour). Treatment results will be compared to control

results.

Data Collection Graph or Sheet: (See Appendix D, Results and Data Comparison)

Results: Passed; the average evaporation reduction was 83.1%, which is greater than 75%.

Discussion of Results: Hexaflex passed this test, although there is certainly room for

improvement; the evaporation that did occur most likely occurred due to the small gaps between

the pieces. Additionally, there are a great deal of variables that could not be controlled due to the

ad-hoc nature of the experimental setup. Further, if the adjustment had not been made for edge

behavior, the measured evaporation reduction would have been far below the target; about 73%.

Recommendations: Given additional resources and time, it would be ideal to run this test in a

larger environment for a greatly extended period of time, at temperatures that would more

realistically model those of the assumed operating environment. Additionally, further testing

would be conducted with full-scale prototypes manufactured out of HDPE through the blow

molding process in order to more accurately model the interaction of the product with its

environment.

Material

Purpose: To measure if HDPE plastic exhibits any degradation when exposed to/in contact with:

● Distilled Water

● Salinity below 2.0%

● pH of 4.5 to 7.5

● UV index below 13


Materials:

● A working computer with internet access

● Water Resistance (Distilled Water) Websites:

○ http://media.wattswater.com/Orion-AW-Chem_Resistance.pdf

○ https://www.newpig.com/wcsstore/NewPigUSCatalogAssetStore/Attachment/doc

uments/ccg/HDPE.pdf

○ http://www.sdplastics.com/kingplastic/HDPE_CRC1.pdf

● Salinity (Seawater) Websites:

○ http://www.solmax.com/wp-content/uploads/2013/12/Solmax-HDPE-Chemical-

Resistance-Chart.pdf

○ http://media.wattswater.com/Orion-AW-Chem_Resistance.pdf

○ http://www.sdplastics.com/kingplastic/HDPE_CRC1.pdf

● pH Websites:

○ http://www.calpaclab.com/chemical-compatibility-charts/#LDPE_HDPE

○ http://pprc.org/index.php/2015/p2-rapid/is-high-density-polyethylene-hdpe-a-

good-choice-for-potable-water/

○ https://plasticpipe.org/pdf/high_density_polyethylene_pipe_systems.pdf

● UV Websites:

○ http://www.dotmar.com.au/uv-resistance.html

○ http://www.plasticmentor.com/97/which-plastic-materials-are-uv-stable/

○ http://rescoplastics.com/plastic-lumber-capabilities

http://media.wattswater.com/Orion-AW-Chem_Resistance.pdf


https://www.newpig.com/wcsstore/NewPigUSCatalogAssetStore/Attachment/documents/ccg/HDPE.pdf


http://www.sdplastics.com/kingplastic/HDPE_CRC1.pdf

http://www.solmax.com/wp-content/uploads/2013/12/Solmax-HDPE-Chemical-Resistance-Chart.pdf





http://www.calpaclab.com/chemical-compatibility-charts/#LDPE_HDPE

http://pprc.org/index.php/2015/p2-rapid/is-high-density-polyethylene-hdpe-a-good-choice-for-potable-water/


https://plasticpipe.org/pdf/high_density_polyethylene_pipe_systems.pdf

http://www.dotmar.com.au/uv-resistance.html


http://www.plasticmentor.com/97/which-plastic-materials-are-uv-stable/


http://rescoplastics.com/plastic-lumber-capabilities




pass. If the majority of the websites state that HDPE does not degrade over time when

exposed to/in contact with water, salinity below 2.0%, pH of 4.5 of 7.5 , and nominal

temperate-equatorial UV levels (given carbon black colorant of 2-6%), the test is passed.

fail. If the majority of the websites state that HDPE does degrade over time when

exposed to/in contact with water, salinity below 2.0%, pH of 4.5 of 7.5, and a UV index

below 13, the test has failed.

Data: Research from the corresponding websites to determine if HDPE meets the criteria outline

(pass/fail).

Data Results:

Distilled Water

Website Criteria Pass or Fail

http://media.wattswater.com/Orion-AW-

Chem_Resistance.pdf

No degradation Pass

https://www.newpig.com/wcsstore/NewPigUSCatalogAsse

tStore/Attachment/documents/ccg/HDPE.pdf

No degradation Pass

http://www.sdplastics.com/kingplastic/HDPE_CRC1.pdf No degradation Pass







Salinity


http://www.solmax.com/wp-

content/uploads/2013/12/Solmax-HDPE-Chemical-

Resistance-Chart.pdf

No degradation Pass

http://media.wattswater.com/Orion-AW-

Chem_Resistance.pdf

No degradation Pass

http://www.sdplastics.com/kingplastic/HDPE_CRC1.pdf No degradation Pass

pH


http://pprc.org/index.php/2015/p2-rapid/is-high-density-

polyethylene-hdpe-a-good-choice-for-potable-water/

No degradation Pass

https://plasticpipe.org/pdf/high_density_polyethylene_pipe_

systems.pdf

No degradation Pass

www.calpaclab.com/chemical-compatibility-charts/ No degradation Pass












http://www.calpaclab.com/chemical-compatibility-charts/

http://www.calpaclab.com/chemical-compatibility-charts/


UV


http://www.dotmar.com.au/uv-resistance.html No degradation Pass

http://www.plasticmentor.com/97/which-plastic-materials-

are-uv-stable/

No degradation Pass

http://rescoplastics.com/plastic-lumber-capabilities No degradation Pass

Results: Passed; HDPE does not degrade over time when exposed to/in contact with its

surrounding environment.

Discussion of Results: This test was very accurate; there were at least 3 sources for each of the

criteria. This ensures that HDPE plastic does not degrade over time when exposed to/in contact

with water, salinity below 2.0%, pH of 4.5 of 7.5, and nominal temperate-equatorial UV levels.

The criteria that was set for Hexaflex was successfully met each time by HDPE, proving that

Hexaflex will remain intact while in its environment and not create or be the source of any

environmental or water hazards.

Recommendations: The type of plastic for Hexaflex does not need to be changed based on this

test. More sources should be used to collect data to further ensure and reinforce that HDPE is the

correct type of plastic to meet the criteria. Industry experts could be consulted to ensure that

HDPE is the ideal material for this type of product.

Rainfall

Purpose: This test will provide quantitative data about the effect of rainfall on Hexaflex,

particularly how submerged Hexaflex become during extended periods of rain.








Initial Conditions:

● The model reservoir is complete and marked along the side in centimeters, with Hexaflex

evenly distributed on surface (see Appendix J, Rainfall and Wave Test Environment)

● Running water source needs to be readily available

● Model reservoir environment should be isolated in order to protect any surroundings from

water damage

Materials:

● Model Reservoir (51cm x 102cm x 13cm)

● 80 Hexaflex (30%)

● Anne Arundel County Tap Water

● Hose and nozzle with shower setting


pass. Must have greater than 40% of its height unsubmerged 5 minutes after the rainfall

ends. There are no puddles of water resting on top of Hexaflex (small droplets are

alright).

fail. Hexaflex has more than 60% of its height submerged.

Procedures:

1. Ensure that initial conditions are met.

2. Fill the model reservoir up to 6 cm.

3. Use a shower setting on the hose. Hold the nozzle 60 cm above the surface of the model

reservoir and directly over top of the center of the model reservoir.

4. Start running the water. When the water level reaches 11 cm, stop running water.


5. Measure how far Hexaflex is submerged, record measurement (% submerged), and

calculate total height submerged given that the height of the prototype Hexaflex is 1.5 cm

(see Appendix E, Hexaflex Submersion Level Guide).

6. Conduct three trials and record all data using the data collection table.


● Suitable precautions must be taken to protect the surrounding environment. This may

include isolating the reservoir environment from any electric equipment.

● Wear safety goggles.

● Be cautious when walking on slippery surfaces.

Data:

● Height of Hexaflex submerged during heavy periods of rain (Percentage of total height,

centimeters)

● Significant amount of water accumulated on top of Hexaflex (Yes/No).


Data Collection Table:

Trial 1:

Rainfall intensity

(L/min)

15

Height of Hexaflex

submerged (cm)

Percent of Hexaflex

submerged (%)

Significant water

gathered on top of

Hexaflex (Yes/No)

Time (Minutes)

0 1.0 67% Yes

5 .75 50% No

10 .75 50% No

Trial 2:

Rainfall intensity

(L/min)

15

Height of Hexaflex

submerged (cm)

Percent of Hexaflex

submerged (%)

Significant water

gathered on top of

Hexaflex (Yes/No)

Time (Minutes)

0 1.0 67% Yes

5 .75 50% No

10 .75 50% No


Trial 3:

Rainfall intensity

(L/min)

15

Height of Hexaflex

submerged (cm)

Percent of Hexaflex

submerged (%)

Significant water

gathered on top of

Hexaflex (Yes/No)

Time (Minutes)

0 1.2 75% Yes

5 .75 50% No

10 .75 50% No

Results: Pass; rainfall did not accumulate on Hexaflex and greater than 40% of its height was

unsubmerged 5 minutes after test.

Discussion of Results: This test was as accurate as possible, given the conditions of the

operating environment and availability of resources. It would not have been feasible to place the

environment in an actual rainstorm because the conditions would not be easily replicable. This

test compensated for the duration of a rainstorm by subjecting Hexaflex to heavy rainfall for a

short period of time. The data gathered was accurate however, measurements were not precise.

While this test provides quantitative data, the main purpose is to collect qualitative data about

water gathering on top of Hexaflex surface. Since Hexaflex did not accumulate water, the design

is satisfactory and there is no need to make changes to it for this test specifically.

Recommendations: The design of Hexaflex does not need to be improved based on this test,

however, improvements could be made to the test procedure. The shower head does provide a

consistent stream of water, however, a true rainstorm will have water drops of various sizes as


well as varying rates and durations of rainfall. Also, the center of the treatment was directly

interacting with the water falling from the shower head, while the rest of Hexaflex were only

getting some of the stray water droplets or mist. The test could be redesigned to cover a larger

surface area of the treatment and also have varying pressures of water. As for data collection, the

accuracy of measuring the depth of Hexaflex could be improved by marking directly on

Hexaflex the submersion level and then measuring with calipers for more precise data.

Stress

Purpose: This test will determine if Hexaflex can withstand its anticipated maximum static load

(to be experienced during transport) without suffering structural failure.

Initial Conditions:

● Inventor is running, stress analysis environment is running

● Top face is being acted upon by 11.64 lbs downward

● Bottom face fixed in place

Materials:

● Computer with Autodesk Inventor 2016

● .ipt File of Hexaflex


pass. All points of Hexaflex have a safety factor of 1.5 or greater.

fail. One or more points on Hexaflex that have a safety factor of less than 1.5.

Procedures:

1. Click simulate button on upper ribbon

2. Select Safety Factor from left option menu, record minimum value



● N/A

Data: Quantitative data representing the amount of load placed on Hexaflex and the stress signs

on Inventor (see image below).

Data Collection Graph or Sheet:

Data: Minimum safety factor is 4.28

Results: Pass; minimum safety factor greater than 1.5.

Discussion of Results: Hexaflex showed no signs of degradation when placed under the load.

This test was as accurate as it could be, given that Inventor was used to identify signs of cracking

and to measure the load. It would not have been as accurate to have measured the load with a

force sensor. Also, Inventor is able to show internal degradation, whereas it would not have been

possible to distinguish weaknesses in person. Inventor made it easier to subject Hexaflex to a

closed environment. No signs of cracking were recognized, demonstrating that Hexaflex is able

to withstand the anticipated load experienced during transport.

Recommendations: Based on the results, the design of Hexaflex does not need to be altered

significantly in any way. The minor signs of degradation on the top of Hexaflex could indicate


that the edges need to be reinforced. However, the more material that is used, the more expensive

the product becomes to manufacture, so the design is acceptable the way it is. On the other hand,

since the minimum safety factor was approximately 285% of the stated minimum, the structural

integrity of Hexaflex could be optimized by reducing the wall thickness and therefore the amount

of material. This test could have given more insight into the design if multiple loads were used.

Waves

Purpose: This test will determine the behavior of Hexaflex when subject to waves of various

amplitudes.

Initial Conditions:

● The model reservoir is complete marked along the side in inches (see Appendix J,

Rainfall and Wave Test Environment)

● Use 20” x 20” x 5” model reservoir

● Disks of 4” and 8” are attached to handle

Materials:

● 1 Model Reservoir (20” x 20” x 5”)

● 50 Hexaflex

● Anne Arundel County Tap Water

● Timer

● Solid disks of diameter 4” and 8” and attachment

● Video camera


pass. Hexaflex maintain proper distribution throughout the waves dissipate.

fail. Hexaflex do not return to proper distribution after the waves dissipate.


Procedures:

1. Ensure that all initial conditions are met and that the reservoir is filled 2.75”.

2. Position setup with 4” disk extended below the water 1.375”.

3. Set a timer for 30 sec and begin moving the plate setup vertically in and out of the water,

being careful that it only breaks the surface the water and then returns to 1.375” each

time. Maintain a constant period.

4. Observe Hexaflex from directly above. Record with a camera for analysis.

5. Review recordings. Analyze the behavior of Hexaflex and record in the observation

section of the data table (see Appendix F, Results and Data Comparison).

6. Repeat this simulation but with the disk starting at the bottom of the model reservoir.

Maintain the same period and be sure that the force applied is reasonable and consistent.

7. Repeat each trial 3 times for both the 4” disk and 8” disks.


● Wear closed-toed shoes and be careful while walking on wet and slippery surfaces


Data: Qualitative observations based on the behavior of Hexaflex while subjected to waves of

variable frequency and amplitude.

Data Collection Graph or Sheet: (See Appendix F, Results and Data Comparison)

Results: Pass; Hexaflex returned to proper distribution after waves dissipated.

Discussion of Results: This test provided the expected results. Hexaflex maintained a

tessellating pattern while subject to waves. There were few gaps between Hexaflex and after

each trial, Hexaflex redistributed quickly and accurately. This test produced consistent results


and is repeatable but is not entirely accurate (see Expert Feedback). Each trial was satisfactory

though, and Hexaflex did not space out more than a few centimeters for the large waves.

Expert Feedback: After discussing this test with Mr. Howard, a few suggestions were made as

to why the test performed as it did. Firstly, the size of the reservoir is not large enough to let the

waves form and dissipate naturally. This resulted in the waves splashing over the size of the

reservoir, as well as Hexaflex. Mr. Howard also mentioned that the device creating the waves is

large in comparison to the size of the model reservoir and Hexaflex. This leads to interference

between the waves and Hexaflex, so a smaller device that is farther away from the testing area

would reduce the influence it has on the behavior of Hexaflex.

Recommendations: Hexaflex do not need to be redesigned because they tessellated accordingly.

However, based on the feedback from Mr. Howard, the test could be improved by using a motor

to create the waves and therefore create a more consistent period and amplitude of waves. This

would also allow the test to be performed several different ways and provide more quantitative

data. Currently, the data is mainly qualitative, as the results are based on observations and

analysis of the movement of Hexaflex. The wave maker could also be situated farther from the

test area so that it does not interfere with the behavior of Hexaflex and the waves themselves. A

model reservoir with sloped sides (possibly concrete as well) would also be an improvement to

the test because it would mimic the edges of an actual reservoir.

Wind (Fan)

Purpose: To determine if 30% scale Hexaflex can withstand constant wind exposure of up to 30

kilometers per hour and redistribute itself quickly after being subjected to high winds.


Initial Conditions:

● Hexaflex are properly installed in the model reservoir (See Appendix J, Wind Resistance

(Fan)).

● Model reservoir should be filled to its maximum capacity, which is 10 gallons (37.8

liters) of water.

Materials:

● Fan (Honeywell, Comfort Control Tower)

● Water (Anne Arundel County tap water)

● Model Reservoir (25.4 cm x 40.8 cm x 30.5 cm fish tank)

● Anemometer

● Timer (Smartphone acceptable)

● 40 Hexaflex (30% scale)


pass. Hexaflex must return to its original distribution within three minutes of the wind

stopping.

fail. Hexaflex is blown out of the reservoir or Hexaflex stack due to the wind blowing

and fail to unstack and redistribute within three minutes of the wind stopping.

Procedures:

1. Place the fan on the shorter side of the reservoir. When using a 25.4 cm x 40.8 cm x 30.5

cm fish tank and the Honeywell brand fan, the base of the fan will rest on a surface 20 cm

above the ground. The fan needs to be sideways and blowing across the surface of the

water.

2. Set the fan to its lowest setting and start timer. Leave fan on for five minutes.


3. Use an anemometer to record the wind speed simulated at each of the fan’s settings.

4. When timer has expired, record how long it takes for Hexaflex to redistribute (see

Appendix K, Pictures of Hexaflex (Properly Distributed)).

5. Record if Hexaflex is being forced against the side of the reservoir or becoming airborne

and leaving the reservoir (see Appendix G, Wind Speed Data Table). Record anything

that affects Hexaflex, such as water gathering on top of Hexaflex or Hexaflex stacking on

top of each other.

6. Repeat steps 2-5 two more times and then again using the fan’s medium setting and then

the fan’s highest setting.


● Do not stand in front of the fan while it is producing high winds.

● Suitable precautions must be taken to protect the surrounding environment. This may

include isolating the reservoir environment from any electric equipment, and possibly

surround the area with some kind of cover to prevent water from escaping the model

reservoir.

● Be cautious when walking on possibly wet and slippery surfaces.

Data: Qualitative data regarding the comments and observations on how Hexaflex react to

different wind speeds. The quantitative data is the time that it takes for Hexaflex to redistribute

after the wind is applied.

Data Collection Graph or Sheet: Refer to Appendix G, Wind Speed Data Table.

Results: Passed; redistribution took less than three minutes.

Discussion of Results: Although Hexaflex was able to redistribute itself in a short amount of

time and not blow away when the fan was blowing, the fan was not strong enough for the testing


needs (20 mph at the least). The test was also subjective and therefore not entirely accurate, so

no final conclusions can be made based on this test.

Recommendations: According to this test no changes are needed to the design of Hexaflex due

to the fact it withstood the wind without flipping or flying away. However, a new test needs to be

created using a wind tunnel to produce a more concentrated wind source and one that would be

able to test wind resistance at different angles and speeds.

Wind Resistance (Version 1)

Purpose: To determine if the scaled down Hexaflex can withstand constant wind exposure of up

to 75 miles per hour and ensure that Hexaflex do not blow out of the reservoir based on the

comparison of lift to weight.

Initial Conditions:

● Hexaflex needs an attachment so it will work in the wind tunnel (see Appendix J,

Hexaflex Attachment)

Materials:

● Wind Tunnel (Jetstream 500)

● Hexaflex (30% scale)

● Wind Tunnel bracket for Hexaflex


pass. If the lift at each varying angle and wind speed is less than the weight of Hexaflex,

the test passes.

fail. If the lift at each varying angle and wind speed is more than the weight of Hexaflex,

the test fails.


Procedures:

1. Mount Hexaflex inside the wind tunnel (see Appendix J, Wind Resistance (Version 1)

Testing Environment).

2. Set the tunnel to 30 mph. The angle of attack should be 0°.

3. Record the lift force, drag force, and lift to drag ratio on the wind tunnel’s outputs (see

Appendix H, Data Collection and Results).

4. Repeat steps 2 and 3 for 45 mph, 60 mph, and 75 mph.

5. After recording the data for 0°, repeat steps 2 through 4 for angles of -30° to 30°,

increasing by increments of 5° each time.


● Wear earplugs.

● Do not use wind tunnel when the instructor is not in the room.

● Be prepared to turn the wind tunnel off quickly if anything goes wrong. (Hexaflex

unmounting and hitting the back of the wind tunnel).

Data: Quantitative data of the lift force and drag force (in Newtons), and the lift to drag ratio at

various angles.

Data Collection Graph or Sheet: Refer to Appendix H, Data Collection and Results.

Results: Inconclusive; new test is needed.

Discussion of Results: The failure to recognize scaling factors makes it difficult to analyze the

results properly. The fact that a complete model was used also alters the results. A new test will

need to be completed that includes the recommendations discussed in the following section.

Recommendations: After running this test, no corrections would be made to Hexaflex, but Mr.

Howard gave a few suggestions about the test itself. First of all, adjustments need to be made to


account for scaling. However, other adjustments need to be made to the test itself, particularly

the model Hexaflex. Currently, airflow is moving both above and below Hexaflex, but for the

purpose of this test, only the top surface needs to be tested, so the model needs to be cut in half.

After testing, Reynold’s number will be necessary for scaling the results to match the scaling of

the model.

Wind Resistance (Version 2)

Purpose: To compare the performance of three different possible designs in heavy winds.

Initial Conditions:

● Hexaflex has wind tunnel attachment hot glued on (see Appendix J, Hexaflex

Attachment)

● Supports of the Plexiglass sheet are taped to the mirror of the wind tunnel. (see Appendix

J, Wind Resistance (Version 2) Attachment of Supports)

Materials:

● Wind Tunnel (Jetstream 500)

● Top Half of Version 1.1- 17° Hexaflex (30% scale)

● Top Half of Version 1.2- 17° Filleted (30% scale)

● Top Half of Version 1.3- “Bubbled” (30% scale)

● 3 Wind Tunnel brackets for prototypes

● Plexiglass sheet

● 4 VEX 3” Aluminum Standoffs

● 4 VEX 5/32” x 1/4" screws

● Duct Tape (To affix insert to wind tunnel base)

Pass or Fail Criteria: N/A


Procedures:

1. Mount the Plexiglas insert on the wind-tunnel base (see Appendix J Wind Resistance

(Version 2) Testing Environment).

2. Mount Hexaflex inside the wind tunnel, so Hexaflex is just above the Plexiglass sheet; set

angle of attack to 0° (see Appendix J, Wind Resistance (Version 2) Testing

Environment).

3. Set the tunnel’s wind speed to 25 mph.

4. Record the lift and drag on the wind tunnel’s outputs (see Appendix I, Data Collection

and Results).

5. Increase the wind speed by increments of 5 mph and record the lift and drag at each

speed. Stop the wind tunnel after recording the data at 50 mph.

6. Repeat steps 2-4 with the two other Hexaflex designs.


● Wear earplugs.

● Do not use wind tunnel when the instructor is not in the room.

● Be prepared to turn the wind tunnel off quickly if anything goes wrong. (Hexaflex

unmounting and hitting the back of the wind tunnel, or the Plexiglass moving out of

place).

Data: Quantitative data of the lift force and drag force (in Newtons)

Data Collection Graph or Sheet: Refer to Appendix I, Data Collection and Results.

Results: 17° filleted performed the best by producing the least amount of lift.

Discussion of Results: The inability to account for scaling factors makes it difficult to analyze

the results beyond a simple comparison between each design that was tested. Version 1.2


produced less lift than version 1.1 after 35 mph, and both versions produced less lift than version

1.3. Version 1.3 should not necessarily be disqualified until more specific tests are run using

Inventor programs, but the importance of making a Hexaflex that does not fly away in heavy

winds must be considered and version 1.3 is more likely to do so than the other two designs. This

test is accurate and repeatable, as each trial was consistently performed. The only possible

inaccuracy is that the Plexiglas underneath Hexaflex was pushing against the model and adding

to the lift force.

Recommendations: A test needs to be conducted on Autodesk Simulation CFD or else

Reynold’s Number must be used to determine how Hexaflex is going to scale and if the final

product can withstand winds of up to 75 mph while it is in the water. The test itself could be

improved by reducing the size of the hole and the space underneath Hexaflex to eliminate a

possible increase in lift force.

Design Refinements/Future Improvements

It is not immediately obvious what changes or improvements need to be made to

Hexaflex. Further tests would need to be conducted, primarily a large scale evaporation

reduction test, in order to pinpoint any functional flaws in the product. These tests would be

focused on the evaporation reduction, wind resistance, and lifespan. It can be speculated that

future refinements would include variations of the fillet and possibly changing the chamfer angle

for better installation.

With the product’s main focus being evaporation reduction, it is clear that the immediate

concern when pilot testing is the ability to limit evaporation. It was speculated that a pilot test

would exhibit greater reduction rates, but if this is incorrect, then changed would need to be

made in regards to the surface area coverage and minimizing the amount of water exposed. Since


the actual shape of Hexaflex would not be changed, an additional feature would need to be

included to ensure the pieces are interlocking appropriately.

A pilot test would provide more accurate results for the ability for Hexaflex to remain

floating in the water when exposed to high winds. If Hexaflex were to become detached from the

surface of the water and blow out of the reservoir during the pilot test, then refinements would

need to be made to the shape or weight of the product, or else more water would need to be

added to the inside of the Hexaflex. It is plausible that the shape of Hexaflex would have to be

further optimized in order to decrease the lift generated. Such optimizations might entail

reducing the chamfer angle or altering how fillets are executed. However, any alterations in

shape would have to still allow Hexaflex to self-distribute.

The last concern is that of lifespan. In order to verify that Hexaflex is cost effective, its

evaporation reduction must be ensured as detailed above, and it must be proven that its

reasonable life span is in excess of 1 years. Ensuring that Hexaflex’s lifespan is greater than 15

years will be the goal of rigorous bench testing. This testing must include but will not be limited

to UV resistance testing, general wear and collision tests, thermal expansion/stress tests, and

water infiltration tests. The goal of these tests will be to ensure that Hexaflex maintains nominal

performance over its lifespan. Nominal performance will have to be established, as will various

accelerations factors which will be used to translate testing data to real-world results and

predictions. These results will then be compared with performance in pilot tests. Presumably,

minor design adjustments will have to be made, then Hexaflex can be safely commercialized.


References

Annual Average Humidity in Texas. (n.d.). Retrieved September 23, 2015, from

http://www.currentresults.com/Weather/Texas/humidity-annual.php

Arizona Reservoir Volumes. (2013, June 30). Retrieved October 14, 2015, from

http://www.climas.arizona.edu/swco/southwest-climate-outlook-july-2013/arizona-

reservoir-volumes

Armor Ball™ AQUA 275. (2013). Retrieved October 7, 2015, from

http://www.awtti.com/armor_balls_aqua_275_cover_info.php

Armor Ball™: Floating cover system. (n.d.). Retrieved from

http://paradisenw.com/armor_ball_cover.php

Ayers, R. (1989). Water quality for agriculture. Retrieved from

http://www.fao.org/DOCReP/003/T0234e/T0234E01.htm

Batra, R. (n.d.). The psychology of design: Creating consumer appeal.

Blanch, D. (2012, February 20). E-Vapcap Dam Cover | Innovations | ABC Radio

Australia. Retrieved from

http://www.radioaustralia.net.au/international/radio/onairhighlights/evapcap-dam-cover

California Water Prices Soar for Farmers as Drought Grows. (n.d.). Retrieved October 11, 2015,

from http://www.bloomberg.com/news/articles/2014-07-24/california-water-prices-soar-

for-farmers-as-drought-grows

Carbon Nanotubes Toughen a Common Plastic. (n.d.). Retrieved October 9, 2015, from

http://phys.org/news/2009-04-carbon-nanotubes-toughen-common-plastic.html

Carlson, R. (n.d.). Copper compounds and algae. Retrieved from

http://www.bassresource.com/fish_biology/algae_copper.html


Chasing Nanocomposites: Plastics Technology. (n.d.). Retrieved October 9, 2015, from

http://www.ptonline.com/articles/chasing-nanocomposites

Climate Prediction Center - Stratosphere: UV Index: Annual Time Series. (n.d.). Retrieved

October 13, 2015, from

http://www.cpc.ncep.noaa.gov/products/stratosphere/uv_index/uv_annual.shtml

ECS Products - About Evaporation Control Systems. (n.d.). Retrieved from


EPA. (n.d.). Retrieved October 9, 2015, from http://www2.epa.gov/recycle/how-do-i-recycle-

common-recyclables

Evaporation Control Systems Products. (n.d.). Retrieved October 7, 2015, from


Extoxnet. (1994, May). Copper Sulfate. Retrieved from

http://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/copper-sulfate-ext.htm

Farm Ponds for Irrigation. (n.d.). Retrieved October 12, 2015, from

http://agwaterstewards.org/index.php/practices/farm_ponds_for_irrigation

Feather, P. (2007, November 7). Structural Engineering: RE: Wind Speeds in California.

Retrieved from http://seaint.blogspot.com/2007/11/re-wind-speeds-in-california.html

Flammability Testing & Ratings For Plastics. (n.d.). Retrieved October 13, 2015, from

http://www.rtpcompany.com/products/flame-retardant/flammability-testing-ratings-for-

plastics/

Flexible Solutions. (n.d.). Flexible Solutions: WaterSavr™: Application Rates and Coverage.

Retrieved from

http://www.flexiblesolutions.com/products/watersavr/application_coverage.shtml


Frey-Klett, P. (2011). Bacterial-Fungal Interactions: Hyphens between Agricultural, Clinical,

Environmental, and Food Microbiologists. Retrieved from

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC32327

Gebelhoff, R. (2015, August 14). 'Shade balls' in L.A. reservoir may look silly, but they'll save

the city 300 million gallons of water a year. Retrieved October 14, 2015, from

http://news.nationalpost.com/news/canada/shade-balls-in-l-a-reservoir-may-look-silly-

but-theyll-save-the-city-300-million-gallons-of-water-a-year

Goldman, D. (2004, September 24). The Physical Hazards of Foreign Materials. Retrieved

October 9, 2015, from http://www.fsis.usda.gov/OPPDE/rdad/FRPubs/02-

033N/ThePhysicalHazardsofForeignMaterials.pdf

HDPE (High Density Polyethylene). (n.d.). Retrieved October 4, 2015, from

http://www.upcinc.com/resources/materials/HDPE.html

Hexprotect™ AQUA: Technical data. (2013). Retrieved October 7, 2015, from

http://www.awtti.com/hexprotect_aqua_cover_info.php

Hexprotect™ MAX R Technical Data. (n.d.). Retrieved from

http://www.awtti.com/hexprotect_max_r_cover_info.php

High Density Polyethylene or HDPE Sheets benefits Architecture and Design, Building and

Construction, Partition and Furniture, Machinery and etc. (n.d.). Retrieved October 9,

2015, from http://www.neuplastics.com/product-advantages/

How The UV Index Scale Works & How To Use UV Index Reports To Avoid A Sunburn | Fun

Times Guide to Weather. (n.d.). Retrieved October 13, 2015, from

http://weather.thefuntimesguide.com/2015/05/uv-index-scale.php


Hudson, B. (2015, January 6). Drying Up Our Water, Part Three | Pagosa Daily Post News

Events & Video for Pagosa Springs Colorado. Retrieved from

http://pagosadailypost.com/2015/01/06/drying-up-our-water-part-three/

IBM discovers new class of ultra-tough, self-healing, recyclable plastics that could redefine

almost every industry | ExtremeTech. (n.d.). Retrieved October 9, 2015, from

http://www.extremetech.com/extreme/182583-ibm-discovers-new-class-of-ultra-tough-

self-healing-recyclable-plastics-that-could-redefine-almost-every-industry

Irrigated Lands Regulatory Program. (n.d.). Retrieved October 9, 2015, from

http://www.waterboards.ca.gov/rwqcb3/water_issues/programs/ag_waivers/index.shtml

Kemsley, J. (2007, November 24). Chemical & Engineering News: Bromate in Los Angeles

Water. Retrieved from https://pubs.acs.org/cen/news/85/i52/8552notw4.html

Lecture Notes. (n.d.). Retrieved October 9, 2015, from

http://classes.mst.edu/civeng120/lessons/thermal/thermal_expansion/index.html

Liquid Innovations! - WaterGuard. (n.d.). Retrieved from

http://www.aquatain.com/WaterGuard.html

Los Angeles Dept. of Water and Power. (2015, August 10). Mayor Garcetti announces

completion of innovative “shade ball” cover project at Los Angeles reservoir. Retrieved

from http://www.ladwpnews.com/go/doc/1475/2578586/MAYOR-GARCETTI-

ANNOUNCES-COMPLETION-OF-INNOVATIVE-SHADE-BALL-COVER-

PROJECT-AT-LOS-ANGELES-RESERVOIR

Martinez, I. (2015). Thermal Effects on Materials. Retrieved October 11, 2015, from

http://webserver.dmt.upm.es/~isidoro/ot1/Thermal effects on materials.pdf

http://www.extremetech.com/extreme/182583-ibm-discovers-new-class-of-ultra-tough-s

http://www.extremetech.com/extreme/182583-ibm-discovers-new-class-of-ultra-tough-s


McKinnon, M. (2015, August 14). Why are Shade Balls Black Instead of White? Retrieved

October 7, 2015, from http://space.io9.com/why-are-drought-balls-black-instead-of-

white-1724040253

National Temperature and Precipitation Maps. (n.d.). Retrieved October 11, 2015, from

https://www.ncdc.noaa.gov/temp-and-precip/us-

maps/ytd/201507?products[]=statewidetmaxrank

New Mexico Of Office of the State Engineer. (n.d.). Water Supply. Retrieved from

http://www.ose.state.nm.us/Planning/RWP/Regions/RioArriba/4-Water-Supply.pdf

White, S. (2010, November 1). Water Markets of the United States and the World.

Retrieved from http://www.thewatercouncil.com/wp-content/uploads/2012/04/EDA-Report.pdf


Appendix A

Rotational Molding:


Injection Molding Drawing (Sonic Welding):


Injection Molding Drawing (Hot Plate Welding):


Blow Molding Drawing:


Appendix B

Diagram of Forces:

Annotation of Physics:

In order for this test to be successful, the angle (𝜃) must be found such that force pulling the object

down the incline is greater than the force of friction resisting motion down the incline.

Setting component of downward force parallel to incline greater than or equal to frictional force:

𝑚𝑔 sin 𝜃 ≥ 𝜇𝑚𝑔 cos 𝜃

Simplifying:

𝑡𝑎𝑛(𝜃) ≥ 𝜇

Solving for θ, given that 𝜇 = .29:

𝑎𝑟𝑐𝑡𝑎𝑛(.29) = 16.6°


Appendix C

Results and Data Comparison:

Sample Results Analysis:


Summary Table:

Control Depth Lost (cm/day) Treatment Depth Lost (cm/day)

.526 .412

.455 -

.487 -

Humidity Instructions:

1. Set the humidity on the dehumidifier to 15-18%

2. Use the relative humidity sensor to measure the humidity in the room. When it reaches

15-18% humidity, the test can begin.

3. While the test is being conducted, use Logger Pro to track the humidity in the room (click

this http://www.vernier.com/products/software/lp/ to open the logger pro program) If the

humidity is ever greater than 18% the test will need to be conducted again.

4. Once an hour, empty the water in the dehumidifier.

Logger Pro Instructions:

1. Click on the link in the Materials section to start the Logger Pro program.

2. The humidity sensor as well as the force plate needs to be plugged into USB ports on the

computer. Cut small holes (1 inch radius) through the plastic section of the environment

and have the wires run through those holes and into the USB ports. Seal the holes that has

wires going through them with duct tape.

3. Click on the Data collection tab.

4. Still in the data collections toolbar, set the mode to time based.

http://www.vernier.com/products/software/lp/


5. Then, set the duration to 4320 minutes (3 days)

6. Click done.

7. Click the zero button near the top of the screen, then start collecting data.


Appendix D

Data Table: Results and Data Comparison

Without Hexaflex With Hexaflex

Time (hours) Water Depth (cm)

0 6.50 6.50

1 6.39 6.44

2 6.25 6.40

3 6.12 6.35

4 5.90 6.30

5 5.60 6.25

Total Depth Lost

(adjusted)

0.90 0.17

Water Loss Ratio: (1-(With/Without)) = (1-(.17cm/.90cm))*100% = 81.1%




0 6.50 6.50

1 6.40 6.47

2 6.25 6.43

3 6.10 6.37

4 6.00 6.34

5 5.75 6.30

Total Depth Lost 0.75 0.11





0 6.50 6.50

1 6.35 6.49

2 6.19 6.45

3 6.08 6.40

4 5.93 6.34

5 5.80 6.30

Total Depth Lost

(adjusted)

0.70 0.12


Avg. Evaporation Reduction: 83.1%


Appendix E

Hexaflex Submersion Level Guide:


Appendix F

Results and Data Comparison

Disk Size: 4”

Small Waves:

Trial Observations

1 Hexaflex remained in the reservoir and had

no issues redistributing after the test was

conducted.

2

3

Large Waves:

Trial Observations

1 Hexaflex remained in the reservoir and had no

issues redistributing after the test was

conducted.

2

3

Disk Size: 8”

Small Waves

Trial Observations

1 Hexaflex redistributed evenly upon

completion of each trial. 2

3


Large Waves

Trial Observations

1 Waves caused water and 4 Hexaflex pieces to

escape the Reservoir.

Hexaflex redistributed evenly upon

completion of the trial.

2 Same as Trial 1

3 9 Hexaflex escaped.

Hexaflex that stayed in the reservoir

redistributed evenly.


Appendix G

Wind Speed Data Table:

Wind speed (mph) Time to Redistribute Comments/ Observations

Low: 5 2 seconds From the start, Hexaflex all moved to one side

of the reservoir with the wind, but afterwards,

quickly moved back into place.

Medium: 10 2 seconds Same as above

High: 15 3 seconds Same as above


Appendix H

Data Collection and Results:

Wind Speed: 30 mph

Angle (degrees) Lift Force (N) Drag Force (N) Lift/Drag Ratio

-30 -0.24 0.39 0.6

-25 -0.17 0.27 0.6

-20 -0.18 0.19 1.0

-15 -0.12 1.33 0.1

-10 -0.04 0.12 0.3

-5 0.00 0.08 0.0

0 0.06 0.11 0.6

5 0.24 0.06 3.9

10 0.16 0.11 1.4

15 0.17 0.14 1.2

20 0.20 0.17 1.2

25 0.24 0.21 1.2

30 0.12 0.26 0.4


Wind Speed: 45 mph


-30 -0.49 0.76 0.6

-25 -0.17 0.27 0.6

-20 -0.44 0.46 1.0

-15 -0.29 0.33 0.9

-10 -0.12 0.27 0.4

-5 0.00 0.22 0.0

0 0.11 0.24 0.5

5 0.32 0.20 1.6

10 0.29 0.25 1.1

15 0.36 0.31 1.2

20 0.44 0.40 1.1

25 0.55 0.51 1.1

30 0.44 1.07 0.4


Wind Speed: 60 mph


-30 -1.06 1.48 0.7

-25 -0.69 1.10 0.6

-20 -0.78 0.79 1.0

-15 -0.53 0.58 0.9

-10 -0.23 0.48 0.5

-5 -0.03 0.44 0.1

0 0.15 0.40 0.4

5 0.41 0.38 1.1

10 0.47 0.44 1.1

15 0.62 0.56 1.1

20 0.78 0.69 1.1

25 0.98 0.88 1.1

30 0.44 1.07 0.4


Wind Speed: 75 mph


-30 -1.35 2.03 0.7

-25 -1.07 1.68 0.6

-20 -1.19 1.22 1.0

-15 -0.83 0.92 0.9

-10 -0.38 0.72 0.5

-5 -0.06 0.67 0.1

0 0.19 0.63 0.3

5 0.52 0.61 0.9

10 0.69 0.68 1.0

15 0.93 0.82 1.1

20 1.20 1.07 1.1

25 1.49 1.36 1.1

30 0.57 1.68 0.3


Appendix I

Data Collection and Results:

Version 1.1- 17° Hexaflex:

Wind Speed (mph) Lift Force (N) Drag Force (N)

25 .00888 0

30 .03108 0

35 .08888 0.0888

40 0.12432 0.12432

45 0.15096 0.14652

50 0.19536 0.19092

Version 1.2- 17° Filleted:


25 0.013344 0.040032

30 0.035584 0.062272

35 0.062272 0.080064

40 0.097856 0.1112

45 0.13344 0.146784

50 0.169024 0.17792


Version 1.3- “Bubble”:


25 0.04448 0.057824

30 0.071168 0.080064

35 0.102304 0.102304

40 0.124544 0.151232

45 0.173472 0.173472

50 0.213504 0.209056


Appendix J

Evaporation Test (Version 1) Testing Environment:

Picture of the Outside of the Environment:

Picture of the Inside of the Environment:


Evaporation Test (Version 2) Environment:


Rainfall and Wave Test Environment:

Wind Resistance Test (Fan):


Wind Resistance (Version 1) Testing Environment:

Hexaflex Attachment:


Wind Resistance (Version 2) Testing Environment:

Wind Resistance (Version 2) Attachment of Supports:


Appendix K

Pictures of Hexaflex (Properly Distributed):


Appendix L

Optimization of Size with Respect to Lift

Documents

Final Technical Report Group #1 Thomas Chaisson, Joelle Cingel, …thomaschaissonportfolio.weebly.com/uploads/7/9/1/6/... · 2018. 9. 4. · Running head: FINAL TECHNICAL REPORT GROUP