PARAMETRIC INVESTIGATION OF PIPE HEAT EXCHANGER · 2017-04-14 · PARAMETRIC INVESTIGATION OF PIPE HEAT EXCHANGER. Shyam Saraiya. 1, Prashant Vakil. 2, Divyanshu Rai. 3 ... The classic

PARAMETRIC INVESTIGATION OF PIPE HEAT EXCHANGER

Shyam Saraiya1, Prashant Vakil

2, Divyanshu Rai

3, Urvesh Patil

4

Student, Mechanical department, Laxmi institute of Technology, Sarigam-Valsad. Gujarat

Corresponding Author Detail:

Prashant Vakil

Student, Mechanical department,

Laxmi institute of Technology,

Sarigam-Valsad, Gujarat.

Internal Guide Detail:

Mr. Hemant Patel & Mr. Jignesh Chaudhri

Assistant Professor, Mechanical department,

Laxmi institute of Technology,

Sarigam-Valsad. Gujarat.

ABSTRACT

In this project, an experimental study on the flows in pipe Heat exchanger is presented. An

experimental setup is fabricated for the estimation of the various Heat Transfer

characteristics. In order to estimate the thermal performance of Pipe Heat exchanger, suitable

instrumentation is employed in the experimental set-up for estimating various parameters

such as temperature measurement and flow measurement. The overall Heat transfer

coefficient is determined by using Reynolds Number, Prandtl Number and Nusselt number.

Heat transfer characteristics inside the pipe heat exchanger for various mass flow rates of

different fluids are compared. The results include temperature and pressure contours and

velocity vectors at several selected cross , distributions of overall heat transfer coefficient and

heat transfer enhancement factor versus different parameters.

KEYWORDS: Pipe heat exchanger, Rota-meter, Pump, Thermocouples, Bypass valve, etc.

INTRODUCTION

A heat exchanger is a device used to transfer heat between one or more fluids. The fluids may

be separated by a solid wall to prevent mixing or they may be in direct contact.They are

widely used in space heating, refrigeration, air conditioning, power stations, chemical

plants, petrochemical plants, petroleum refineries, natural-gas processing, and sewage

treatment. The classic example of a heat exchanger is found in an internal combustion

engine in which a circulating fluid known as engine coolant flows through radiator coils

and air flows past the coils, which cools the coolant and heats the incoming air.

TYPES OF HEAT EXCHANGER

1. SHELL AND TUBE HEAT EXCHANGER

Shell and tube heat exchangers consist of series of tubes. One set of these tubes contains the

fluid that must be either heated or cooled. The second fluid runs over the tubes that are being

heated or cooled so that it can either provide the heat or absorb the heat required. A set of

tubes is called the tube bundle and can be made up of several types of tubes: plain,

longitudinally finned, etc. Shell and tube heat exchangers are typically used for high-pressure

applications (with pressures greater than 30 bar and temperatures greater than 260 °C). This

is because the shell and tube heat exchangers are robust due to their shape.

International Journal of Scientific Research in Engineering (IJSRE) Vol. 1 (3), March, 2017

IJSRE Vol. 1 (3), March, 2017 www.ijsre.in Page 148

Figure-1 Straight tube heat exchanger

2. SPIRAL HEAT EXCHANGER

A modification to the perpendicular flow of the typical HCHE involves the replacement of

shell with another coiled tube, allowing the two fluids to flow parallel to one another, and

which requires the use of different design calculations. These are the Spiral Heat Exchangers

(SHE), which may refer to a helical (coiled) tube configuration, more generally, the term

refers to a pair of flat surfaces that are coiled to form the two channels in a counter-flow

arrangement. Each of the two channels has one long curved path. Pair of fluid ports are

connected tangentially to the outer arms of the spiral, and axial ports are common, but

optional. The main advantage of the SHE is its highly efficient use of space.

3. PLATE HEAT EXCHANGER

Another type of heat exchanger is the plate heat exchanger. These exchangers are composed

of many thin, slightly separated plates that have very large surface areas and small fluid flow

passages for heat transfer. Advances in gasket and brazing technology have made the plate-

type heat exchanger increasingly practical. In HVAC applications, large heat exchangers of

this type are called plate-and-frame; when used in open loops, these heat exchangers are

normally of the gasket type to allow periodic disassembly, cleaning, and inspection. There are

many types of permanently bonded plate heat exchangers, such as dip-brazed, vacuum-

brazed, and welded plate varieties, and they are often specified for closed-loop applications

such as refrigeration. Plate heat exchangers also differ in the types of plates that are used, and

in the configurations of those plates. Some plates may be stamped with "chevron", dimpled,

or other patterns, where others may have machined fins or grooves.

4. REGENERATIVE HEAT EXCHANGER

In a regenerative heat exchanger, the same fluid is passed along both sides of the exchanger,

which can be either a plate heat exchanger or a shell and tube heat exchanger. Because the

fluid can get very hot, the exiting fluid is used to warm the incoming fluid, maintaining a near

constant temperature. A large amount of energy is saved in a regenerative heat exchanger

because the process is cyclical, with almost all relative heat being transferred from the exiting

fluid to the incoming fluid. To maintain a constant temperature, only a little extra energy is

need to raise and lower the overall fluid temperature.



5. ADIABATIC WHEEL HEAT EXCHANGER

In this type of heat exchanger, an intermediate fluid is used to store heat, which is then

transferred to the opposite side of the exchanger unit. An adiabatic wheel consists of a large

wheel with threads that rotate through the fluids—both hot and cold—to extract or transfer

heat.

METHODOLOGY

PART SPECIFICATION

1.Pump

Kirloskar self priming pump

Capacity :0.5 HP, Inlet & Outlet diameter :25 mm

Head :6 to 24 m, Speed :2700 rpm

2.Heat Exchanger

Pipe heat exchanger

No of Thermocouple :07 ,Type :K-type

No of Heater :06 ,Type :Bend type

Pipe Length :300 mm, Pipe Diameter :25 mm

3.Rota-meter Glass Tube Rota-meter

Range :0-1000 LPH

4.Voltmeter

Digital Voltmeter

Aux Supply :230 V AC,50 Hz

Range :0-500 V AC

5.Temperature

Indicator

Digital Temperature Indicator

No of indicator: 2, Supply :230 V AC

6.Tank

Square Tank

Size : 180*180*120 mm

Volume :38.88 l

7.Manometer U-Tube Manometer, Range :0 to 250 mm

8.Dimmer Single Phase Dimmer, Range : 0-260 V

9.Switch MCB, Toggle

Table-1 Part Specification

Study of research Paper Study of mechanism Selection of material

Design of Experimental set up Analysis Fabrication & assembly

Check for no leakage Conduct Experiment, note observation &

compare

re



EXPERIMENTAL TEST SET UP

Assembly & setup of project is shown in figure.

Figure-1 Project Setup

OBSERVATION TABLE

Voltage

(V)

Mass flow

Rate

(LPH)

T(1)

(C)

T(2)

(C)

T(3)

(C)

T(4)

(C)

T(5)

(C)

T(6)

(C)

T(7)

(C)

P

(cm)

100

400 43 42 42 44 45 49 50 21

600 44 42 43 45 46 50 53 20.7

800 45 44 45 46 47 51 54 20.5

150

400 41 40 41 43 44 48 51 21

600 45 43 44 46 46 51 53 20.8

800 46 44 45 47 47 52 54 20.5

200

400 45 44 44 46 47 51 54 20.8

600 47 46 46 48 48 53 56 20.9

800 48 46 47 49 48 53 57 20.2

Table-2 Observation Detail



CALCULATION

We have obtained number of readings of temperature& pressure at different voltage & mass

flow rate in pipe heat exchanger at different location. From above readings, parametric

calculation of pipe heat exchanger are given below;

We know, Pipe Diameter (D): 25mm = 0.025 m

Pipe Length (L): 300mm = 0.3m

At V = 100V&m = 400 LPH,

T(1) = 43, T(2) = 42, T(3) = 42, T(4) = 44, T(5) = 45, T(6) = 49, T(7) = 50 in C

∆T = T(7) – T(1) = 50 – 43 = 07 C = 7 + 273 = 280 K

P = 21 cm = 0.21 m

At ∆T= 280 K, Specific heat (Cp) =1.003 kcal/kgK

Density ( ) = 999.96 kg/m^3

Thermal conductivity (k) = 0.5715 W/mK

Viscosity (µ) = 0.001429kg/ms

We know that 1LPH = 0.00028 LPS

So, m = 400 * 0.00028

So, m = 0.112 LPS

Surface area of pipe, A = π*D*L

= 3.1416*0.30*0.025

So, A = 0.023562 m^2

Now, Heat transfer co-efficient, q” = hA∆T(1)

Where, Heat Flux q” = Q/A ,∆T(1) = Tsurface –Tbulk

But Q = m*Cp*∆T = 0.112 *1.003 *280

So, Q = 31.45

Thus, q” = Q/A = 31.45/0.023562

So, q” = 1334.77 watt

Tsurface = T(2) + T(3) + T(4) + T(5) + T(6) / 5 = 42 + 42 +44 + 45 + 49 / 5 = 44.4 C

Tsurface = 317.4 K

Tbulk = 2 T(1) + T(7) / 2 = 2 (43) + 50 / 2 = 86 + 50 / 2

Tbulk = 68 K

∆T(1) = Tsurface – Tbulk = 317.4 – 68

∆T(1) = 249.4 K

Substituting all value of q” , A , ∆T(1)in h = q” /A∆T(1)

We get , h = 1334.77 / 0.023562 * 249.4 = 1334.77 / 5.876

So, h = 227.15 W/m^2 K

Now, Reynold number , Re = ρvD / µ

But, Velocity (v) = m /ρ A = 0.112 / 999.96 * 0.023562 = 0.112 / 23.56 = 4.753 * 10 ^-3

So, v = 0.74 m/s

Thus, Re = ρ v D / µ = 999.96 * 0.749 * 0.025



So, Re = 1200

So, flow is laminar.

Nusselt number ,Nu = h D / k = 227.15 * 0.025 / 0.5715

So, Nu = 9.9365

Prandtl number ,Pr =µ Cp / k = 0.001429 * 1.003 / 0.5715

So, Pr =0.00250794

Similarly, we will calculate all parameter of heat exchanger at different voltage and mass

flow rate for various reading from observation table.

COMPARISON

Comparison & analysis of various fluid parameters are given in table.

Diameter

(D)

m

Density

( ρ)

Kg/m^3

Thermal

Conductivity

(k)

W / mK

Specific

Heat (Cp)

kcal

/kgK

Viscosity

(μ)

Kg / ms

Heat

transfer

coefficient

(h) W/m^2

K

Water

(Experiment) 0.025 999.96 0.5715 1003 0.001429 227.15

Water+Ethylene

Glycol (30%) 0.025 1030.7 0.49185 3754.8 0.001501 349.7035

Ethylene Glycol 0.025 1106.6 0.25405 2444.1 0.012671 383.9669

Water+ Ethylene

Glycol (50%) 0.025 1048.7 0.43641 3314.2 0.002707 373.7272

Table-3 Comparison of fluid parameter

CONCLUSION

From this experiment, we can conclude that

When mass flow rate increase , Temperature increase ,but pressure decrease and

Water has lowestheat transfer coefficient where as Ethylene Glycol has highest at

same mass flow rate & voltage.

FUTURE SCOPE

We can check for maximum heat transfer coefficient of given fluid in other type of heat

exchanger like shell and tube heat exchanger ,plate type heat exchanger ,etc. by

replacing pipe heat exchanger.

We can try to improve the heat transfer coefficient obtain in this experiment by some

suitable mean & will try to do project for different fluid other than Ethylene Glycol and

Water.



REFERENCE

1. R.K.Rajput, Heat and Mass Transfer.

2. Frank P. Incropera & David P. Dewitt, Fundamentals Of Heat And Mass Transfer, ssPp

642-643.

3. S.N. Sridhara1*, S.R. Shankapal2 And V. Umesh Babu3 " Cfd Analysis Offluid Flow

And Heat Transfer In A Single Tube-Fin Arrangement Of An Automotive Radiator" ,

International Conference On Mechanical Engineering 2005

4. S.M. Peyghambarzadeh , S.H. Hashemabadi, S.M. Hoseini, M. Seifi Jamnani

"Experimental study of heat transfer enhancement using water/ethylene glycol based

nanofluids as a new coolant for car radiators.

5. K.Y. Leong a,b, R. Saidur a,*, S.N. Kazi a, A.H. Mamunc " Performance investigationof

an automotive car radiator operated with nanofluid-based coolants (nanofluid as a coolant

in a radiator)" , 30 March 2010.

6. S. Toolthaisonga,* and N. Kasayapananda " Effect of attack angles on air side thermaland

pressure drop of the cross flow heat exchangers with staggered tube arrangement", 10th

Eco-Energy and Materials Science and Engineering (EMSES2012)

7. Aytunc， Er , Barı_ Ozerde , Levent Bili , Zafer _Ilke " Effect

ofgeometrical parameters on heat transfer and pressure drop characteristics of plate fin

and tube heat exchangers, 2004

8. Mr. Amol B. Dhumne And Prof. H. S. Farkade " Heat Transferanalysis Of Cylindrical

Perforated Fins In Staggered Arrangementa Review.



Documents

PARAMETRIC INVESTIGATION OF PIPE HEAT EXCHANGER · 2017-04-14 · PARAMETRIC INVESTIGATION OF PIPE HEAT EXCHANGER. Shyam Saraiya. 1, Prashant Vakil. 2, Divyanshu Rai. 3 ... The classic