Cat.mec. Dei Fluidi 41 Engl

8/12/2019 Cat.mec. Dei Fluidi 41 Engl

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LABORATORY of

FLUID MECHANICS

Cat. n. 41


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CONTENTS

1. HYDRAULICS BENCH Mod HB/EV

2. DEAD WEIGHT CALIBRATOR Mod HB1/EV

3. CENTRE OF PRESSURE Mod HB2/EV

4. FLOW OVER WEIRS Mod HB3/EV

5. STABILITY OF A FLOATING BODY Mod HB4/EV

6. BERNOULLIS THEOREM DEMONSTRATION Mod HB5/EV

7. IMPACT OF A JET Mod HB6/EV

8. FLOW THROUGH ORIFICES Mod HB7/EV

9. BOTTOM ORIFICE DISCHARGE Mod HB8/EV

10. ENERGY LOSSES IN PIPES Mod HB9/EV

11. FLOW CHANNEL Mod HB10/EV

12. OSBORNE REYNOLDS DEMONSTRATION Mod HB11/EV

13. METHODS OF FLOW MEASUREMENTS Mod. HB12/EV


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14. ENERGY LOSSES IN BENDS AND FITTINGS Mod HB13/EV

15. FREE AND FORCED VORTEX Mod HB14/EV

16. HYDRAULIC RAM Mod HB15/EV

17. DEMONSTRATION PELTON TURBINE Mod HB16/EV

18. SERIES/PARALLEL PUMPS Mod HB17/EV

19. CENTRIFUGAL PUMP CHARACTERISTICS Mod HB18/EV

20. CAVITATION DEMONSTRATION Mod HB19/EV

21. MULTIPURPOSE FLOW CHANNEL Mod HB20/EV

22. FLUID FRICTION APPARATUS Mod HB21/EV


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Elettronica Veneta S.p.A. - 31045 Motta di Livenza (TV) Italy - Via Postumia,16 - Tel.+39 0422 7657 (r.a.) - Fax.+39 0422 860784

Export: Tel. +39 0422 765802- Fax +39 0422 861901- http://www.elettronicaveneta.comE-mail: [email protected]

HYDRAULICS BENCH

mod. HB/EV

DescriptionThe bench has been designed to study thebehaviour of fluids and the hydraulic theory.It is a support module for various complementaryaccessories that enable to test the fluid mechanics.The upper part of the bench consists of an openchannel that can house some complementarymodules, and of two tanks of known volume for avolume measurement of flow rate. An external sighttube with scale enables to read the water levelinside these tanks.A dump valve is installed in the bottom of thevolumetric tank; this valve allows the water flows

into the supply tank available at the base of thehydraulic bench.The water is drawn to the top of the bench by acentrifugal pump, whereas the flow rate is adjustedthrough a control valve.A variable-area flowmeter enables to compare theflow rate read on the instrument, to the flow ratemeasured through the measuring tanks.

Training program

Measurement of flow rates

TECHNICAL CHARACTERISTICS

Hydraulics bench built completely in stainlesssteel and mounted on wheels

Centrifugal pump of stainless steel - 0.37 kW,maximum flow rate of 80 l/min, maximum headof 20 m

Variable-area flowmeter

Capacity of the supply tank: 120 litres

Upper tank for measuring volume flow: 10litres, for low flow rates; 40 litres, for high flowrates

Control valve for adjusting flow rate

Discharge valve on the base of the upper tankfor water recycling inside the supply tank

Open channel at the top with the function ofsupporting various modules

Services required

Tap water for filling the supply tank

Single-phase power supply

Chonometer

Theoretical-experimental texts

- Theoretical-experimental handbook


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DEAD WEIGHT CALIBRATORmod. HB1/EV

Description

This equipment enables to calibrate a pressuregauge by applying prefixed pressures.It consists of a piston running inside a cylinder thussupplying a certain pressure to the liquid enteringthe cylinder.

A supporting plate at the top of the piston enablesto apply several weights and consequently differentand prefixed pressures to the system.The cylinder-piston assembly is connected with the

pressure gauge of the equipment.

Training program

- Calibratine a Bourbon gauge

TECHNICAL CHARACTERISTICS- Bourbon gauge: scale 0 - 2.5 bar

- Diameter of piston: 10 mm- Mass of piston + weight supporting plate: 0.5kg

- Ancillary masses: 2 x 0.5 kg; 1 x 1 kg

Services required

Hydraulics bench


- Theoretical-experimental handbook


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CENTRE OF PRESSURE

mod. HB2/EV

Description

The module enables to determine the hydrostaticthrust exerted by a fluid on a submerged surface.A body of toroidal shape mounted on a balancearm is introduced into a plexiglas tank.When the quadrant is immersed in the tank, theforce exerted by the water on the perpendicularsurface gives rise to a moment with respect to thefulcrum that provokes a variation in the arminclination.A counterweight is positioned at the end of thebalance arm to counterbalance the momentexerted by the water until the arm returns to itshorizontal position. The value of hydrostatic thrustcan be determined from the applied weights.A graduated scale drawn on the plexiglas tankenables to assess the hydrostatic thrust of thewater when the water level varies inside it.

Training program

- Determining the centre of hydrostatic pressureon a surface submerged completely or partiallyand compariing with the theoretical position

- Determining the resulting compression force byusing counterbalance weights

Determining the compression force when thewater level varies


- Capacity of plexiglas tank: 6 litres- Distance between suspended mass andfulcrum: 275 mm

- Inside diameter of quadrant: 100 mm- Outside diameter of quadrant: 200 mm- Depth of the quadrant: 75 mm- Height of fulcrum above quadrant: 100 mm

Weights supplied: two of 10 g, two of 20 g, four of100 g, one of 50 g

Services required

Hydraulics benchThis module can also work autonomously.

Theoretical-experimental textsTheoretical-experimental handbook


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FLOW OVER WEIRS

mod. HB3/EV

Description

The module enables to assess the characteristicsof flow over weirs with different shapes.A rectangular notch and a vee notch weir are usedin the flow channel of the Hydraulic Bench.A quick release connector in the base of thechannel is unscrewed and a delivery nozzlescrewed in its place. A baffle enables to reduceliquid turbulence thus ensuring a more regular flow.Lowering a fixed measuring rod onto the freesurface of water and using a graduated scaleenable to measure the level inside.

The measurement system is applied onto the sidewalls of the channel and it can be moved along thechannel to the required position.The used weirs are fastened to their carriermounted at the end of the channel, by screws.

TECHNICAL CHARACTERISTICS- Overall dimensions of weir plates: height of

160 mm; width of 230 mm- Dimensions of rectangular notch: height of

100 mm; width of 90 mm

- Angle of vee notch weirs: 60, 90- Range of level indicator: 0-200 mm

Services required

Hydraulics bench


Theoretical-experimental handbook

Training program

- Assessing the flow characteristic over a rectangular notch- Assessing the flow characteristic over a vee notch- Determining the discharge coefficient


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STABILITY OF A FLOATING BODY

mod. HB4/EV

Description

The equipment enables to investigate the factorsaffecting the stability of a floating body.It consists of a plastic rectangular floating pontoon,the centre of gravity of which can be varied byadjustable weights sliding on a horizontal rod andit can be clamped in any position on a verticalmast.Moving these weights will enable to pass from a

stable equilibrium situation to another situation ofunstable equilibrium, and to determine themetacentre position.A plumb-bob suspended from the mast indicatesthe angle of heel on a calibrated scale.Use this equipment on the Hydraulics Bench afterfilling the upper tank with water.

Training program

determining the centre of gravity of the pontoon

determining the metacentric height and theposition of the metacentre for the stability of

the pontoon

variation of metacentric height with angle ofheel

TECHNICAL CHARACTERISTICSPontoon dimensions:

- length: 350 mm

- width: 200 mm- overall height: 475 mm

Max. angle of heel: 13 that correspond to a

linear dimension of 90 mm

Services requiredHydraulics bench




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Elettronica Veneta S.p.A. - 31045 Motta di Livenza (TV) Italy - Via Postumia,16 - Tel.+39 0422 7657 (r.a.) - Fax.+39 0422 860784Export: Tel. +39 0422 765802- Fax +39 0422 861901- http://www.elettronicaveneta.comE-mail: [email protected]

BERNOULLIS THEOREM DEMONSTRATION

mod. HB5/EV

Description

The equipment enables to study the Bernoullistheorem through the use of a classical Venturi.A series of wall tappings allow measurement of thestatic pressure distribution along the convergingduct, wherea a measurement of dynamic pressure iscarried out along the centre line of the section afterthe venture meter.

The pressure tappings are connected with a set ofpressure gauges pressurized by a hand pump.Water is fed through a hose connector and iscontrolled by a flow regulator at the outlet oftheequipment.The venture meter can be used for flowmeasurements and it is possible to determine thedischarge coefficient.

Training program

demonstration of Bernoullis theorem and of itslimitations

directl measurement of the static and total(static + dynamic) pressure distribution along aVenturi tube

tubo Venturi

determining the discharge coefficient atvarious flow rates

variation of metacentric height with angle ofheel


Pressure gauges:number of pressure gauges : 7

range of pressure gauges: 0-500 mm.w.c.- Diameter of Venturi: 25 mm- Throat diameter: 10 mm

- Upstream taper: 14

- Downstream taper: 21




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IMPACT OF A JET

mod. HB6/EV

Description

This apparatus enables to measure the forcedeveloped by a jet of water impinging upon astationary object.It consists of a cylindrical transparent vessel insidewhich water is fed from the bottom: the water isdischarged vertically through a nozzle and it hits anobject carried on a stem which extends through the

cover.A system for counterbalancing the impact of the jetis mounted on the upper end of this stem; thissystem consists of a weight carrier with weights.A height indicator of the weight carrier on the coverof the cylinder enables to adjust the equilibriumposition of the forces. When there is a water jet, theforce exerted by the jet leads to a stem extensionand it is counterbalanced by the addition of weightsonto the top until the weight pan returns to thestarting position.Thus the force exerted by the water jet on thestationary object can be determined.

A total of four targets are provided: a flat target, a120 cone, a 30 cone and a hemispherical target.

Training program

Measuring the force exerted by a water jet ondifferent targets and comparing with theresults predicted by the momentum theory.

TECHNICAL CHARACTERISTICS- Diameter of cylinder: 180 mm- Height of cylinder: 300 mm

- Nozzle diameter: 8 mm, 5 mm- Distance between nozzle and target: 20 mm- Diameter of target plate: 30 mm- Target plates:

- hemispherical target

- 45cone- flat target

- Set of weights




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FLOW THROUGH ORIFICES

mod. HB7/EV

Description

This equipment enables to calibrate two orificesof different diameter and to determine thedischarge coefficient.The equipment consists of a tank fed with waterfrom the Hydraulics Bench.The orifice is installed at the base of the tank bymeans of a special wall fitting which provides aflush inside surface.The head inside the tank is kept at a constantvalue by an adjustable overflow and is indicatedby a level scale.A jet trajectory tracing device allows the pathfollowed by the jet to be ascertained.

Training program

- Determining the coefficient of velocity for asmall orifice

- Experimental determination of thedischarge coefficient for a small orifice with

flow under constant head and flow under

varying head- Comparing the measured trajectory of a jet

with that predicted by theory of fluidmechanics


- Orifice diameters: 4 mm and 8 mm- Jet trajectory probes: 8- Height of overflow: 410 mm

Services required

- Hydraulics bench





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BOTTOM ORIFICE DISCHARGE mod. HB8/EV

DESCRIPTIONThis module consists of a cylindrical glass tankwith an orifice fitted in the base.used to studythe flow.The water fed from the hydraulics bench entersfrom the top through a system that eliminatesthe turbulence inside, whereas an overflowkeeps the level constant.A traverse assembly is installed under the tank:this enables to position a pitot tube anywhere inthe jet. A sharp graduated blade attached to thispitot tube is crossed by the jet to measure the

jet diameter and the vena contracta diameter,thus the contraction coefficient can becalculated.The static head and the total head across theorifice are shown on manometer tubes adjacentto the tank.In addition to the standard orifice, supplyincludes five additional orifices

Training program

Determining the velocity coefficient for asmall orifice

Calculating the discharge coefficient for a

small orifice with constant or variable flow Comparing the detected trajectory of a jet

with that predicted by the theory of fluidmechanics.

TECHNICAL CHARACTERISTICS- Orifice diameters: 4 mm and 8 mm- Jet trajectory probes: 8- Height of overflow: 410 mm

Services required

- Hydraulics bench





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Export: Tel. +39 0422 765802- Fax +39 0422 861901- http://www.elettronicaveneta.comE-mail: i [email protected]

ENERGY LOSSES IN PIPES

mod. HB9/EV

Description

The equipment enables to measure the pressuredrop of a liquid flowing through a circular pipe.It consists of a test pipe, oriented vertically, whichmay be fed directly from the Hydraulics Bench orfrom an internal constant head tank.The flow rate can be controlled by a valve on the

discharge line of the pipe.Head loss between two tapping points in the testpipe is measured by two pressure gauges: a waterover mercury gauge for large pressure drops, anda pressurized water gauge for small pressuredrops.Water discharging from the head tank returns tothe supply tank of the Hydraulics Bench.

Training program

- Determining the pressure drops along the pipeas the water flow varies

- Investigating the effects of laminar and

turbulent flow regimes


Diameter of test pipe: 4 mmLength of test pipe: 560 mmDistance between pressure tappings points: 510mmRange of mercury gauge: 0-500 mmRange of water gauge: 0-500 mm

Cylinder capacity: 1000 ml

Services required

- Hydraulics bench




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FLOW CHANNELmod. HB10/EV

DESCRIPTIONThis module enables to study the characteristics of

flow in an open channel.The channel is fed with the water coming from thehydraulics bench via a stilling tank that reduces theturbulence of the liquid.The channel, made of transparent acrylic material,is high and narrow and incorporates weirs ofadjustable height at the inlet and at the outlet tocontrol the liquid level inside.This apparatus is also equipped with a dye injectionsystem consisting of a reservoir, of a flow controlvalve and of a graticule allowing a bettervisualization of the flow according to the differenthydrodynamic models available in the central part

of the channel.The water coming from the flow channel isdischarged into the hydraulics bench and it returnsto the supply tank of this bench for being recycled.

Training program

Demonstrating the basic principles of the openchannel flow

Visualization of flow patterns over or around

immersed objects of different shape and size

TECHNICAL CHARACTERISTICS Dye injection needles: 5

Dye reservoir capacity: 0.45 l

Width of channel: 20 mm

Length of channel: 625 mm

Depth of channel: 150 mm

Available hydrodynamic models:- broad crested weir- narrow crested weir- symmetrical aerofoil- asymmetrical aerofoil- small cylinder- large cylinder





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OSBORNE REYNOLDS DEMONSTRATIONMod HB11/EV

Description

The equipment reproduces the Osborne Reynoldsexperiment concerning the nature of laminar andturbulent flow.It consists of a header tank where water comingfrom the hydraulics bench is made to pass throughsome glass marbles to reduce the water turbulence.The flow through the pipe can be adjusted through acontrol valve in the discharge line.Using the volumetric tank of the hydraulics benchenables to measure the flow rate of water crossingthe pipe. Thus the velocity of water can bedetermined and Reynolds number calculated.The equipment uses a dye injection system for aneasier observation of flow conditions inside thetransparent pipe.

Training program

Reproducing the classic experiments conductedby Osborne Reynolds concerning fluid flowcondition

Observing the laminar, transitional, turbulentflow and determining the velocity profile


- Test pipe diameter: 10 mm- Lenght of test pipe: 700 mm- Dye reservoir capacity: 250 ml- Supply tank: 3.5 litres

Services required

- Hydraulics bench




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METHODS OF FLOW MEASUREMENTSMod HB12/EV

Description

The equipment enables to carry out threemeasurements of flow rate using a Venturi meter, acalibrated orifice and a variable area flow meterconnected in series to enable direct comparison.A flow control valve enables to vary the flow ratecrossing the circuit.Each instrument incorporates some pressuretappings so that its head loss may be measured.

These tappings are connected to a pressure-gaugebank of eight tubes pressurized by a hand pump.The circuit and pressure gauges are mounted on asupport framework standing on the working top ofthe Hydraulics Bench. This bench is used as sourceof water supply and to calibrate each flow meter withits volumetric tanks.

Training program

Direct comparison of flow measurements carriedout with a Venturi meter, a variable area flowmeter and and orifice plate

calibrating each flow meter by using thevolumetric tank of the hydraulics bench

comparing pressure drops across eachinstrument

TECHNICAL CHARACTERISTICSRange of pressure gauges: 0-500 mm. w.c.Number of manometer tubes: 4Orifice plate diameter: 20 mmVariable area flow meter: 0.1-1 m/hVenturi dimensions:

- throat diameter: 15 mm- upstream pipe diameter: 31.75 mm

- upstream and downstream taper: 21/14

Services required

- Hydraulics bench




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ENERGY LOSSES IN BENDS AND FITTINGSmod. HB13/EV

DescriptionThis equipment enables to calculate the energylosses through some elements of a hydrauliccircuit such as bends, sudden contractions andenlargements, control valves, etc

The equipment is mounted on a framework fixedonto the hydraulics bench.

The fittings available in this equipment for thestudy of head losses are:

mitre bend

90 elbow

sweep bend of small radius

sweep bend of large radius

sudden contraction

sudden enlargement.

Each fitting has two pressure tappings: thesetappings are connected with a bank of 12 water

manometers thus enabling to measure the headloss through them.

Another element of this equipment is a valveequipped with pressure tappings for head lossmeasurements; these tappings are connectedwith a differential pressure gauge mounted on thesupporting framework.

A gate valve available at the outlet is used toadjust the flow rate of water.This module is fed through the hydraulics bench.


Pipe diameter: 20 mm

Differential pressure gauge: 0-3 bar

Enlargement diameter: 26 mm

Contraction diameter: 20 mm Fittings:

45 mitre

elbow

short bend

large bend

enlargement

contraction

Pressure gauge range: 0-440 mm

Number of manometer tubes: 12

Differential pressure gauges: 6




Training program

Measuring the losses in the devices related toflow rate and calculating the respectivecoefficients

Comparing the pressure drop across eachdevice


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FREE AND FORCED VORTEX

mod. HB14/EV

Description

The equipment has been designed to study thecharacteristics of free and forced vortices inside acylinder of acrylic cylinder.The free vortex is generated by water dischargingthrough an interchangeable orifice available at thebase of the cylinder and the resulting profile ismeasured with a vortex height measuring systemplaced in the upper part of the cylinder, and with ameasuring instrument of the vortex diameter at

different depth.The forced vortex is induced by a paddle in the baseof the cylinder which is rotated by jets of waterentering through pipes with particular inclinations.Velocity at any point in the free or forced vorticesmay be measured with 3 Pitot tubes placed atdifferent distances from the centre.

Training program

- Understanding the difference between free andforced vortices

- Determining the surface profile of a forcedvortex

- Determining the surface profile of a free vortex


- Tank diameter: 250 mm- Tank height: 300 mm- Orifice diameters: 8, 12, 16, 24 mm- Distance from centre of vortex height

measuring probes: 0, 30, 50, 70, 90 and 110mm

- Pitot tubes at: 15, 25, 30 mm radius- Inlet tubes diameters: 9, 12.5 mm- Inlet tubes inclination:

60for diameter of 9 mm15for diameter of 12.5 mm

Services required

- Hydraulics bench




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HYDRAULIC RAM

mod. HB15/EV

DescriptionThis equipment enables to study the effect of thewater hammer inside pipes; this occurs whenflowing water is suddenly brought to rest and a

pressure wave travels along the pipe. Theequipment includes two tanks at different heightsand a pump operating according to the principle ofthe hydraulic ram; this pump consists of a pulsevalve that closes when the water arrives at highspeed (high kinetic energy) and of a non-returnvalve. An air vessel above the valve chambersmooths cyclic fluctuations due to the ram pump.The lower tank is fed by the hydraulics bench,whereas the water flows from the upper tank backto the hydraulics bench. Some weights aresupplied so that they can be applied to the pulse

valve to change the closing pressure and hencethe operating characteristics.

Training program

- Establishing flow/pressure characteristics anddetermining efficiency of the hydraulic ram


Height of the lower tank: 880 mm

Height of the higher tank: 1150 mm

Capacity of the pump: 0.025 litres/s







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DEMONSTRATION PELTON TURBINE

mod. HB16/EV

Description

The equipment consists of a miniature Peltonturbine with spear valve arrangement mounted on asupport standing on the top of the HydraulicsBench.The Pelton turbine has a horizontal shaft; a nozzleproduces horizontal jets tangent to the buckets thathave a flow splitter in the centre and are shaped in

such a way that the water flow coming out has anopposite direction with respect to the inlet flow.The bottom of the casing is open to allow the waterleaving the buckets be drained into the hydraulicsbench.The front face of the casing is transparent allowingan easy observation of the behaviour of the waterjet on the buckets.Mechanical output from the turbine can bemerasured through a dynamometer that consists ofa 60mm-diameter brake wheel fitted with a bandtensioned by a weight hanger from one side and bya spring balance from the other side.

Pressure at the nozzle can be read on a pressuregauge.

Training program

- Determining the operating characteristics(power, efficiency, torque) of a Pelton turbine atvarious speeds of its rotor


- Speed range: 0 to 2000 r.p.m.

- Power: 10 W- Pressure gauge: 0 to 2.5 bar- Number of Pelton buckets: 20- Outer diameter of Pelton wheel: 100 mm- Two 10-N dynamometers

Services required

- Hydraulics bench




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mo d. HB17/EV

Description

Introducing a second pump to the HydraulicsBench enables to study two pumps in seriesand parallel configuration.The module consists of a fixed speed pumpinterconnected by flexible tubing to the firstpump.The auxiliary pump is mounted on a supportwhich stands adjacent to the primary pump of

the Hydraulics Bench.The equipment has three Bourdon gauges, acompound gauge to be mounted in suction ofthe pump, and the other two pressure gauges inthe discharge of the two pumps.The accessory comprises a flow rate regulatingvalve.Moreover a Y accessory with two valves isavailable for the connection in parallel.

Training program

- Drawing of the curve H(Q) of a centrifugal

pump- Series connection of two pumps with samecharacteristics

- Parallel connection of two pumps withsame characteristics


- Pump: of centrifugal type max. head: 22 meters of water column max. flow rate: 80 l/h

- Motor rating: 0.37 kW- Pressure gauge range: 0 to 6 bar- Compund gauge range: -1 to 2.5 bar- Flow rate regulating valve- Two-way valve

Services required

- Hydraulics bench- Single-phase power supply + Gz



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CENTRIFUGAL PUMP CHARACTERISTICS

mod. HB18/EV

Description

This module is similar to the module HB17/EVwith the difference that the auxiliary pump hasvariable speed with inverter drive.The pump is mounted on a support adjacent tothe pump of the hydraulics bench.The motor speed, output voltage and motorcurrent can be monitored directly on theinverter display. Moreover on the control paneloffers the possibility of modifying the pumpspeed.A pressure gauge is mounted directly on thepump inlet, whereas another pressure gauge ismounted on the pump outlet.A discharge manifold including a pressuregauge, a flow control valve and diffuser is alsoavailable.

Training program

- Drawing of the curve H(Q) for a centrifugalpump- Plotting the curves of head, power, speed

and efficiency versus flow rate- Series connection of two pumps with same

characteristics

- series connection of two pumps withdifferent characteristics

- Parallel connection of two pumps withsame characteristics

- Parallel connection of two pumps withdifferent characteristics

TECHNICAL CHARACTERISTICS- Pump: of centrifugal type

max. head: 22 meters of water columnmax flow rate: 80 l/h

- Motor power: 0.37 KW- Variable speed: 0 to 1500 rpm- Pressure gauge: 0 to 6 bar- Compound gauge: -1 to 2.5 bar

Services required

- Hydraulics bench

- Single-phase power supply + G



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CAVITATION DEMONSTRATION UNIT

mod. HB19/EV

Description

This apparatus mounted on the hydraulicsbench is used to demonstrate the phenomenonof cavitation.It consists of a Venturi tube manufactured from

clear acrylic to allow an easy visualization insidethe section.When water flow rate increases, pressure at thethroat is reduced complying with the Bernoulliequation until the vapour pressure of the liquidis reached and small bubbles of vapour formand then they collapse violently as the pressurerises again downstream; this phenomenon iscalled cavitation.Bourdon gauges indicate the pressure upstreamof the contraction, inside the throat anddownstream of the contraction.Flow control valves before and after the test

section enable to adjust flow and pressure sothat the phenomenon of cavitation can bedemonstrated.

Training program

- Observation of the phenomenon ofcavitation in a liquid

- Comparing theoretical and effectivepressure in cavitation conditions

- Observation of air release due to gases inthe liquid

- Demonstrating how cavitation is reduced bythe rise of the static pressure in a liquid

TECHNICAL DETAILS- Pressure gauge

- before the throat: 63 mm diameter; 0-1bar

- at the throat: 100 mm diameter; -1-0 bar- after the throat: 63 mm diameter; 0-1 bar

The module can work independently from theHydraulics Bench using cold water with flowrate of 0.4 l/s at a pressure of 2 bar.

Services required- Hydraulics bench



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MULTI PURPOSE FLOW CHANNEL

mod. HB20/EV

Description

This module has been conceived to demonstrate theprinciples of fluid mechanics when applied toengineering structures in open channel flow.The apparatus consists of a open flow channel,available in lengths of 2.5 m and 5 m, with clearacrylic sides for an easier visibility of the flow; thechannel is fed by an inlet tank and is designed forfree discharge into the Hydraulics Bench.

The channel is mounted on a rigid framework and itcan be tilted thanks to a calibrated screw jack.The inlet tank is designed to ensure a uniform flow.The level in the working section of the channel iscontrolled by an overshot weir at the discharge end.A lot of objects being fixed to the channel base aresupplied, for a better teaching of fluids mechanic.A longitudinal scale available at the top of thechannel allows depth gauges and Pitot-static tubesfor speed measurements to be positioned along thechannel length.The channel has been designed to be used withthe hydraulics bench that provides the pumped

water flow, the flow control valve and a volumetrictank for flow measurement.

Training program

- Using depth gauges to measure water level- Using a Pitot-static tube to measure flow rate- Applying force-momentum and steady flow

energy equations to simple flow situations- Understanding the relationship between water

level above the crest of a weir and flow rateover the weir

- Using hydraulic structures such as syphon

spillways, to control level- Understanding sub- and super-critical flow and

the underlying characteristics of waves- Hydraulic jump- Using hydraulic structures such as sluice

gates, for control of flow- Applying and understanding Mannings

formula- Measurement of velocity profiles


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- Dimensions: HB-20-2.5 HB-20-5.0- Length 2.91m 5.41m- Width 0.62 m 0.62 m- Height 1.46 m 1.46 m

- Channel dimensions:- Width 76 mm- Height 250 mm

Channel slope: adjustable between 1% and3%

Models supplied:

- Venturi tube- Sharp crested weirs- Broad crested weirs- Crump weir- Adjustable undershot weir- 2 Vernier level gauges

Optional available models:

HB-20-1: Pitot tube and pressure gaugeHB-20-2: Culvert fitting, one edge square, oneroundedHB-20-3: Flow splitters of different shapeHB-20-4: Free overflow spillway section ofdifferent shape, complete with ski jump, slopingapron and blended reverse curvatureattachmentsHB-20-5: Syphon spillwayHB-20-6: Radial gateHB-20-7: Wave generator and wave absorbingbeachHB-20-8: False floor sections for graduallyvaried profilesHB-20-9: Artificially roughened bed section withlength of 2.5 mHB-20-10: Thin-plate (triangular, Cipoletti,Bazin) weirHB-20-11: Broad crested weirHB-20-12: Parshalls device

Services required

- Hydraulics bench




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FLUID FRICTION APPARATUS

mod. HB21/EV

Description

The module is used to study fluid friction lossesthrough pipes of different diameters, valves andflow metering devices.The unit consists of a framework which supportsthe network of pipes and fittings for test.

In detail, four smooth pipes of differentdiameters and one roughened pipe are used.The pipe having to be tested will be isolatedthrough a valves system without beingdisconnected.Pressure drops are measured through pressuretappings positioned immediately before andafter the element.One of the pipe sections is equipped with aVenturi, an orifice plate and a Pitot tube.The module is equipped with a watermanometer for measurements of pressuredrops; this is connected with the pressuretappings of the element whose loss must becalculated.

Training program

Demonstrating the relationship betweenhead losses and velocity of fluid

Determining the head loss of a flowthrough pipes of different diameters, fittingsand metering devices

Determining the relationship betweenfriction coefficients and Reynolds numberfor flow through a pipe with roughened

bore Demonstrating the application of different

systems for measuring flow rate and fluidvelocity

Practical training of pressure measurementtechniques


- Overall Dimensions:Height: 1.10 mWidth: 2.Depth: 0.43 m

- Test pipe inside diameter: 17.2 mm, 10.9mm, 7.7 mm, 4.5 mm

- Inside diameter of roughened pipe: 15.2mm

- Test pipe length: 1000 mm- Number of tapping points: 38- Venturi meter- Orifice plate- Pitot tube

Services required

- Hydraulics bench



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ELETTRONICA VENETA spa - 31045 Motta di Livenza (Treviso) ITALYVia Postumia. 16 Tel. +39 0422 7657 r.a. Fax +39 0422 861901 www.elettronicaveneta. com

All rights reserved. No part of this publication may be reproduced, stored in any retrieval system, or transmitted in any form or by any means,

electronic, mechanical, photocopying, recording, or otherwise without the prior writen permission of Elettronica Veneta S.p.a.

Documents

Cat.mec. Dei Fluidi 41 Engl