Experimental Investigation on the Effect of Fluid Flow Rate on the Performance of a Parallel Flow Heat Exchanger

Transcription

1 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) Experimental Investigation on te Effet of Fluid Flow Rate on te Performane of a Parallel Flow Heat Exanger Cristian O. Osueke, Antony O. Onokwai Adeyinka O. Adeoye Department of Meanial Department of Meanial Department of Meatronis Engineering Landmark University Engineering Landmark University Engineering Afe Babalola University, Omu-Aran, Kwara State, Nigeria Omu-Aran, Kwara State, Nigeria Ado-Ekiti,Ekiti State, Nigeria Abstrat -- Te pervading industrial importane of Heat exanger in eat transfer is one of te major motivations to arry out tis work. A plate eat exanger is a type of eat exanger tat uses metal plates to exange eat between two liquids wit ig density fluid. Tis resear foused on te use of an extended plate eat exanger using water as working fluid. Tis resear work deals wit an experimental Investigation on te effet of Fluid Flow Rate on te Performane of a Parallel Flow Heat Exanger. Te extended plate eat exanger onsists of plates overall dimensions: 75mm by 115mm. Effetive diameter: 3.mm, plate tikness:.5mm, wetted perimeter: 153.mm and Projeted eat transmission area:.8m 2 per plate. Te study was limited to te pysial arateristis and termal performane of a parallel flow eat exanger stationed at te Meanial Engineering Laboratory of landmark University. Experimental results in te form temperature distribution and flow rates were analyzed to generate te termal performane measures of te eat exanger. Te study was limited to te pysial arateristis and termal performane of a parallel flow eat exanger stationed at te Meanial Engineering Laboratory of landmark University. Experimental results in te form temperature distribution and flow rates were analyzed to generate te termal performane measures of te eat exanger. Experimental results in te form temperature distribution, veloity and flow rates, were analyzed to generate te Reynolds numbers, Nusselt numbers, Prandtl numbers, termal performane, logaritmi mean temperature differene onvetive and overall eat transfer oeffiient of te eat exanger. It was deduted tat rise in effiieny requires faster inrease in flow rate of te ot stream tan of te old stream. Also te eat transfer oeffiient inreases wit Reynolds NumberNusselt number. Inrease in Reynolds and nusselt number is an indiation tat flow is beoming more turbulent and results into iger eat transfer rates.wit tis work as foundation, reommendations for future resear inluded more advaned study tat would involve determination of temperature distribution by solving eatmass transfer equation. Tis level of analysis will require knowledge of termal properties and boundary onditions. It was also reommended tat ounter-urrent flow of same faility be investigated for instrutive omparison wit te studied parallel flow under te bakground of teoretial result tat given mass flows and temperature differenes, te ounter-flow eat exanger requires less surfae area (tus less lengt) tan its parallel flow equivalent Keywords- Extended plate eat exanger, termal effiieny, flow rate, Convetive eat transfer oeffiient, Overall eat transfer oeffiient, Reynolds number, nusselt number. I Introdution Heat exanger is a devie in wi transfer of termal energy takes plae between two of more fluids aross a solid surfae. Tese exangers are lassified aording to onstrution, flow arrangement; number of fluids, ompatness, et. Te use of eat exanger gives iger termal effiieny to te system. In many appliations like power plants, petroemial industries, air onditioning et. eat exangers are used. Plate eat exanger is generally used in dairy industry due to its ease of leaning and termal ontrol. Te plate eat exangers are built of tin metal eat transfer plates and pipe work is used to arry streams of fluid. Plate eat exangers are widely used in liquid to liquid eat transfer and not suitable for gas to gas eat transfer due to ig pressure drop [1]. A plate eat exanger is a type of eat exanger tat uses metal plates to exange eat between two liquids. Tis as a noteworty favorable position more tan a onventional eat exanger in tat te liquids are presented to a mu bigger surfae range in ligt of te fat tat te liquids spread out over te plates. Tis enourages te exange of eat, and enormously builds te pae of te temperature ange. Plate eat exanger onsists of parallel metal plates tat are orrugated bot to inrease turbulene and to provide meanial rigidity. Tese normally ave four flow parts, one in ea orner, and are sealed at teir outer edges and around te ports by gaskets, wi are saped to prevent external leakages and to diret te two liquid troug te relatively narrow passages between alternate pairs of eat transfer plates. Te plates are lamped togeter in a frame tat inludes onnetions for te fluid. All wetted parts are aessible for inspetion by removing te lamping bolts and rolling bak te removable over [2] , IJIRAE- All Rigts Reserved Page -1

2 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) R. K. Sa and S. G. Kandilkar [3], ave experimentally investigated te influene of number of termal plates on effetiveness of eat exanger for 1 pass 1, 2 pass 1, 3 pass 1 flow arrangements and number of plates up to 41. Results were plotted for number of plates and F, NTU and F, for 4 different pass arrangements. Tey onluded, for 1pass1 flow arrangement wit an even number of termal plates, fluid in te outermost annels is same. Te eat transfer rate of multi pass arrangement may be iger or lower tan tat of 1pass1 for same N and R wi depends upon eat transfer arateristis of plate material. For N < 4, end effet is onsiderable. Wen tere is signifiant imbalane in flow rates, R < 2, 1pass1 arrangement is desirable. For (R=2, 3) 2pass1 arrangement is desirable and for R > 4, 3 pass 1 arrangement is desirable and for 1 pass 1 exanger wit an even number of termal plates te fluid in outermost annel is same. Te exanger effetiveness is sligtly iger if outer fluid as iger eat apaity as ompared to oter fluid aving one less flow annel. [4] H. Dardour, S. Mazouz, and A. Bellagi [5] ad done numerial analysis of te termal performane of a plate type eat exanger wit parallel flow onfiguration. Te omputation is based on te effetiveness- NTU model. Te numerial results illustrate te evolution of te most important parameters of te plate eat exanger. A parametri analysis is presented wi brings out te effet of NTU and te R parameter, te eat apaity rate ratio, on te performane of te plate eat exanger (PHE). To ek te validity of te presented simplified model establised to desribe te energy balanes in te PHE and te numerial seme adopted, simulated performane as been ompared to te performane evaluated by teoretial relations. Comparison sows an exellent agreement between tem. Te temperature gradients troug ea annel and eat fluxes troug ea ative plate are also evaluated. [6] Murugesan M.P. and Balasubramani [7] Performed test for te investigation of milk adesion and te stability of te oatings on orrugated plates. A number of oatings and surfae treatments were tested. Heat exanger plates oated wit different nanoomposites as well as eletro polised plates installed in te eating setion of te pasteurizer were tested. Signifiant differenes were observed between oated and unoated plates. Te oated plates sowed tat redued deposit buildup in omparison wit te unoated stainless steel plates. Te time required for leaning plae wit te oated plates was redued by 75% ompared to standard stainless steel plates [8]. Tey also investigate eat transfer performane of plate type eat exanger experimentally by varying operating parameters and design parameters. Heat transfer oeffiient was studied for various fluids like water and etylene glyol. Te inrease mass flow rate wit subsequently inrease in te flow veloity as led to an inreased overall eat transfer oeffiient as well as individual eat transfer oeffiient. [9] T K S Sai Krisna, S G Rajasekar, C Pravarakya [1] modeled te plate type eat exanger in solid works and te fluid flow analysis is done on te modeled fluid part. Te analysis stated tat wen te tikness of te plates dereases ten te eat flow is iger and if te number of plates inreases ten te outlet temperature differene of te fluids inreased and te pressure ontour stated tat, tere is little pressure drop in te entry and outlet of te fluid, From te turbulent ontour it is interfered tat tere is very ig turbulene in te entry and outlets due to sudden ange in ross setion along te plates. [11] Tis paper fouses on an experimental investigation of te performane of a parallel flow eat exanger as well as te effet of fluid flow rate wit respet to overall eat transfer oeffiient. II METHODOLOGY A. Experimental Set Up 1) Test Proedure: Te plate eat exanger wit flat plates is used for trials.te fluids used are ot and old water. Two flow arrangements implemented wi are parallel flow and ounter flow. Trials onduted wit different mass flow rate of ot and old water and also ot water inlet flow rate was kept onstant wile old water inlet flow rate varied. Proedure repeated for getting more aurate results and results plotted Fig.1 Hydrauli ben Fig.2 Extented plate eat exanger , IJIRAE- All Rigts Reserved Page -11

3 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) 1. Base Plate 2. Fixed endplate 3. Heat exanger plates 4. Moving end plate 5. Frame 6. Central bolt 7. Intermediate plate Fig. 3 Extended plate eat exanger mounted on servie unit Fig. 4 Hydrauli ben ontaining te fluid and extended plate eat exanger mounted on a servies unit. B. Equipment details TABLE 1 EXTENDED PLATE HEAT EXCHANGER Plates overall dimensions 75mm by 115mm Effetive diameter Plate tikness Wetted Perimeter Projeted eat transmission area 3.mm.5mm 153.mm.8m 2 per plate. Cirulating Pump Pump Motor Rating Sump Tank Capaity Hig-Flow Volumetri Tank Capaity Hig-Flow Volumetri Tank Capaity TABLE 2 HYDRAULIC BENCH Type: Centrifugal Max. Head: 21m Water Max. Flow: 8litresmin(Using Volumetri tank) Max. Flow: 1litresmin(Using appropriate aessory).37kw 25litres 4litres 6litres , IJIRAE- All Rigts Reserved Page -12

4 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) TABLE 3 SERVICE UNIT Heigt- Lengt- Dept- Hot Water Vessel Capaity C. Assumptions 1) Te plate eat exanger operates under steady state onditions, 2) No pase ange ours; bot fluids are single pase and are unmixed, 3) Heat losses to surrounding are negligible, 4) Te temperature in te fluid streams is uniform, 5) Te fluids ave onstant speifi eats, 6) Te fouling resistane is negligible, 7) Pressure drop aross eat exanger is negligible. 43mm 1mm 5mm 1.5litres. TABLE 4 PROPERTIES OF WATER AT MEAN TEMPERATURE. Property Unit(Metri) Hot Water (Mean Temperature) Heat Capaity(C p ) KJKgK Termal Condutivity(K) WmK Dynami Visosity Nsm Density(ρ) Kgm Speifi Volume(v) M 3 Kg Absolute Pressure KNm Speifi Entropy KJKgK Cold Water (Mean Temperature) Te two integrated forms of eat transfer equation of 1% effiient parallel-flow and ounter-flow (wit ot fluid being te reversed flow) eat exanger are ± ± Q = T T (1) UA = ln (2) were m and m are te mass flow rate of te old and ot fluids respetively, and are te speifi eat apaities of te old and ot fluids respetively, Q is te total eat exange between te ot and old fluid steams, T and T are te temperature differenes between te ot and old fluid steams at te outlet and inlet of te eat exanger respetively, U is te overall eat transfer oeffiient and A is te eat exange area. Dividing equation (2) wit equation (1) and rearranging gives Q = UA (3) ( ) It is seen from equation (3) tat te logaritmi mean temperature differene T is T = ( ) Wen Q is viewed as UA T. At 1% effiieny all te eat emitted by te ot stream is absorbed by te old stream. Wen te eat exange between te ot and old fluid steams is not 1% effiient, te following nomenlature are introdued; rate of emission of eat or eat power emitted by te ot stream Q, rate of absorption of eat or eat power absorbed by te old stream Q and overall effiieny η. Tese are respetively given by Q = m T (5) Q = m T (6) η = = (7) Were T and T are magnitude of te temperature differenes between te outlet and inlet of te ot and old streams respetively. Te overall eat transfer oeffiient sould ave been given as U = Q (A T ) if not for pysial onstrution tat sometimes auses a deviation from eiter 1% parallel flow or 1% ounter flow. Tis is taken are of by introdution of orretion fator f su tat , IJIRAE- All Rigts Reserved Page -13 (4)

5 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) U = = Te value stipulated for f in te user manual of te extended plate eat exanger is.95 ten U =. =. (8a) (8b) D. Qualitative and Tabular Analysis of Experimental Results Te studied system is in parallel flow meaning tat T = T T and T = T T (see figure 5) ten T = (T T ) (T T ) ln[(t T ) (T T )] (2.9) Tis is better understood by a simplified diagram of te studied mode of flow as given in fig. 5 below T T T 1 2 T3 4 ot T 5 old T6 T7 T T 8 9 T1 Fig. 5 A simplified diagram of te experimental parallel flow eat exanger Te dedution is tat T is only realisti wen T > T and T > T. For matematial justifiation of tis point suppose T > T and T > T ten te denominator of equation (9) gives ln[ k] = ln[ 1 k] = ln[ 1] + ln[k] = x (1) Were te positive real number k is given by k = (T T ) (T T ) =-(T T ) (T T ) =(T T ) (T T ). Equation is rewritten based on te omplex number teory as ln[ k] = ln[exp(jπ)] + ln[k] = jπ + ln[k] = x (11) were j is te unit magnitude omplex number 1. Te dedution from equation (11) is tat te ondition T > T and T > T auses te denominator x to ave a omplex value and ene auses T to ave a omplex value wi is not supposed to be so. Te onlusion is tat te realisti ondition for tere to be real and positive value for T is T > T and T > T. Tese are onditions tat are onsistent wit te first and seond laws of termodynamis. Te experimental results from te extended plate eat exanger are given in table 5. Te experimental runs tat do not meet wit te neessary ondition T > T are put in red in table 5. Tis experimental runs are onsidered invalid and are not analyzed furter in wat follows. Table 5 is re-presented as table 6 ontaining only te relevant experimental runs. Also in table 6 are presented te volumetri flow rates in m 3 s -1 and te omputed values of te flow apaities m and m. Tis value make omputations easier as will be seen in wat follows. 1) Area of te flow : A = 3na were 3 is te number of ative plates per pak for te studied eat exanger, n = 4 is te number of paks utilized in te experiment and a =.8 is te projeted eat transfer area of every plate ten A = =.96m 2) Hydrauli Diameter: It is te ratio of ross setional area of te annel to te wetted perimeter of te annel 4A D H P Were, A= Area of Flow in m 2, P= wetted Perimeter of te plate in m and 4x m.153 D H = Hydrauli Diameter , IJIRAE- All Rigts Reserved Page -14

6 3) Veloity of flow: International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) V m A Were, A= Area of flow in m 2, ρ= Density in Kgm 3 and m = mass flow rate in Kgse. Veloity for Cold Water V m s.96x997.1 Veloity for Hot Water V m s.96x ) Reynolds Number: It is te ratio of inertia fores to visous fores. Re = inertial foresvisous fores D Re H VD H Were, V= mean veloity of te objet relative to te fluid in ms D H =Hydrauli Diameter in m =dynami visosity of te fluid in Nsm 3 =Kinemati visosity ( ) in m 2 s =density of te fluid in Kgm 3 Reynolds Number for Cold Water V D Re H 997.1x.22461x Reynolds Number for Hot Water V D Re H 994.1x.3489x ) Prandtl Number: It is te ratio of momentum diffusivity (kinemati visosity) to termal ondutivity. P r = Visous diffusion ratetermal diffusion rate V C P p r K V= Kinemati visosity, V (m 2 s) , IJIRAE- All Rigts Reserved Page -15

7 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) K = Termal diffusivity, = (m 2 s) C p =Dynami visosity (Nsm 2 ) C p =Speifi eat (JKgk) K = Termal Condutivity (Wmk) =Density (Kgm 3 ) P r Prandtl Number for Cold Water V C p K.6312x4.181 r Prandtl Number for Hot Water.6284x4.181 r ) Nusselt Number: It is te ratio of onvetive to ondutive eat transfer aross te boundary. DH Nu K Were, = Heat transfer oeffiient D H = Hydrauli visosity in m K = Termal ondutivity in WmK Nu = Nusselt Number Nusselt Number for Cold Water: D Nu K Nu Nu H.662 Re.5 P.33 r.662x x Nu Nu.662 Re Nusselt Number for Hot Water D Nu K.5 P.662x r.5 x , IJIRAE- All Rigts Reserved Page -16

8 NO of Exp EXP NO of Exp T 1 T 1 T 2 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) T 2 T 3 T 3 TABLE 5 EXPERIMENTAL RESULTS OBTAINED FROM THE EXTENDED PLATE HEAT EXCHANGER TABLE 6 RESULTS OF HOT AND COLD FLOW RATES AND THERMAL CAPACITY TABLE 7 RESULTS OF THERMAL EFFICIENCY AND OVERALL HEAT TRANSFER COEFFICIENT T 4 T 5 T 6 T 7 T 8 T 9 T 1 m p T1 - T 1 T 4 T 5 T 6 T 7 T 8 T , IJIRAE- All Rigts Reserved Page -17 m p T 5 T - 6 T in n U ( W m 2 K) T 1 F ot Liters per se F old Liters per se T2 T4 1 T -T5 T1 -T T 1 T 2 T 3 T 4 T 5 T 6 T 7 T 8 T 9 T 1 q ot ( m 3 s) q old ( m 3 s) m p m p x x x x x x x x x x x x x x x x x x x x m m p p

9 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) TABLE 8 RESULTS OF REYNOLDS NUMBER, PRANDTL NUMBER, NUSSELT NUMBER, HEAT TRANSFER COEFFICIENT AND OVERALL HEAT TRANSFER COEFFIECIENT. Re Re P r P r Nu Nu H H Fig. 6 Grap of te ratio of old to ot termal apaity against overall eat transfer oeffiient From fig. 6 above te overall eat transfer oeffiient of te eat exanger approximately falls wit rise in te ratio of termal apaities Fig. 7 Grap of te ratio of old to ot termal apaity against termal effiieny Fig. 7 above, effiieny of te eat exanger approximately inreases wit rise in te old stream flow rate. Tis is aieved by making sure tat te ot stream flow rate is stationary , IJIRAE- All Rigts Reserved Page -18

10 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) Grap of te flowrate ratio for oldot fluid against intermidiate temperature E-67.6E-66.55E-64.95E-69.6E-62.79E-53.29E-52.1E-52.3E-53.1E T7-T9 T1-T5 T1-T6 QoldQot Fig. 8 Flow rate ratio for oldot fluid against intermediate temperature One important observation from fig. 8 above is tat intermediate temperatures for te extended plate eat exanger inrease as te flow rate ratio for oldhot fluid inreases; tis is as a result of inrease in te old water flow rate wile te ot water flow rate is kept onstant at a low temperature. Te first intermediate temperature for te eat exanger as te maximum temperature tat is 1 o, tus possesses iger termal effiieny. Te intermediates temperatures derease as te flow rate ratio between te old to ot stream inreases, wile tat of te tird intermediate temperature inrease gradually. Tis is due to te inrease in te pressure from te ydrauli ben. Te first and seond intermediate temperatures are equal wen te flow rate is 6.55E-6 and 2.1E-5 respetively. Wile tat of first and seond intermediate temperature are te same, wen te flow rate is 4.95E-6. 1.E+1 8.E+ 6.E+ 4.E+ 2.E+ QoldQot Tin.E Fig. 9 Grap of Logaritmi Mean Temperature Differene against Ratio of Cold to Hot flow rate From fig. 9, te temperature driving fore for eat transfer inreases as te flow rate inreases until it get to te maximum point wen te flow rate is 5.5m 3 s, after tat, it dereases gradually as te flow rate ontinue to inreases at 8m 3 s. Overall Heat Transfer Coeffiient(U) in Wm2K) Reynolds Number (Re) Fig. 1 Grap of old reynolds number against overall eat transfer oeffiient , IJIRAE- All Rigts Reserved Page -19

11 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) Overall Heat Transfer Coeffiient(U) in Wm2K) Reynolds Number (Re) Fig. 11 Grap of ot reynolds number against overall eat transfer oeffiient Fig Sows te variation of Reynolds against onvetive eat transfer oeffiient. From te figure, it is dedue tat te onvetive eat transfer oeffiient inreasesdereases wit an inrease in Reynolds number. Tis is due to te inreasederease in te ratio of inertia to visous fores in te fluid. Overall Heat Transfer Coeffiient (Wm2K) Nusselt Number(Nu) Fig. 12 Grap of old nusselt number against overall eat transfer oeffiient Overall Heat Transfer Coeffiient (U) (Wm2K) Nusselt Number(Nu) Fig. 13 Grap of ot nusselt number against overall eat transfer oeffiient Fig Sows a gradual inrease and derease in overall eat transfer oeffiient wit an inrease in Nusselt number. Te inrease in overall eat transfer oeffiient is as a result te orresponding inreasederease in te ratio of onvetive to ondutive eat transfer aross te boundary , IJIRAE- All Rigts Reserved Page -2

12 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) Convetive Heat Transfer Coeffiient (H) (Wm2K) Cold Reynolds Number(Re) Convetive Heat Transfer Coeffiient (H) Wm2) Fig. 14 Grap of old reynolds number against eat transfer oeffiient Hot Reynolds Number (Re) Fig. 15 Grap of ot reynolds number against eat transfer oeffiient Fig Sows te grap of onvetive eat transfer oeffiient against Reynolds number. From te figure, it is dedue tat te onvetive eat transfer oeffiient inreases wit an inrease in Reynolds number due to inrease in te variation of te inertia fores applied to te eat exanger, wile te dereases is as a results of derease in te inertia to visous fores in te eat exanger. Inrease in Reynolds number sows tat te flow is turbulent and lead to a ig rate of eat transfer. Convetive Heat Transfer Coeffiient(H) Nusselt Number (Nu) Fig. 16 Grap of old nusselt number against eat transfer oeffiient , IJIRAE- All Rigts Reserved Page -21

13 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) Convetive Heat Transfer Coeffiient(H) Hot Nusselt Number (NU) Fig. 17 Grap of ot nusselt number against eat transfer oeffiient Fig Sows te grap of onvetive eat transfer oeffiient against Nusselt number. From te figure, it is dedue tat te onvetive eat transfer oeffiient sligtly inrease wit an inrease in Nusselt Number, leading to a more ative onvetive, wit turbulent flow. Te derease in onvetive eat transfer oeffiient is as a result of derease in onvetive eat transfer aross te boundary. Overall Heat transfer Coeffiient (Wm2K) Mass Flow Rate (Kgs) Fig. 18 Grap of mass flow rate against overall eat transfer oeffiient Fig. 18 above sows te variation of overall eat transfer oeffiient against mass flow rate. From te figure, it is dedue tat te overall eat transfer oeffiient inreases wit an inrease in mass flow rate. Tis is due to te inrease in te flow veloity wi an also lead to inrease in te eat transfer rate. III CONCLUSION Tis resear fouses on an experimental investigation of te effet of fluid flow rate on te performane of a parallel flow eat exangers in an extended plate wit regard to termal effiieny, overall eat transfer oeffiient, onvetive eat transfer oeffiient, flow rate, and Reynolds number. Pysial arateristis and termal performane of a real eat exanger were studied in tis work. Te eat exanger was supplied to te Meanial Engineering laboratory of Landmark University wit te model name HT3XC Heat exanger Servie Unit. Te detailed desription of te unit is given in is as given in te previous setion. Even toug te Unit an be onfigured for eiter parallel or ounter-urrent flow by anging te diretion of te pump ontrolling te ot water flow, only te o-urrent flow was studied in tis work. Te experimental results tat violet te laws of termodynamis were onsidered experimental outliers and disarded. Using te experimental results te termal performane arateristis of te eat exanger wi inlude; effiieny, overall eat transfer oeffiient and logaritmi mean temperature differene were alulated for all te experimental runs. Te relationsip between te first two and te ratio of termal apaities was presented grapially.it was seen from te grap tat effiieny of te eat exanger falls wit rise in. In oter words it an be stated tat rise in effiieny requires faster inrease in flow rate of te ot stream tan of te old stream. Also, It was seen tat te overall eat transfer oeffiient approximately falls wit rise in. It an also be stated tat rise in overall eat transfer oeffiient requires faster inrease in flow rate of te ot stream tan of te old stream. Tere is variation of onvetive eat transfer oeffiient wit respet to mass flow rate. Also te onvetive eat transfer oeffiient inreases wit bot Reynolds and nusselt numbers, wi inreases te overall eat transfer oeffiient , IJIRAE- All Rigts Reserved Page -22

14 International Journal of Innovative Resear in Advaned Engineering (IJIRAE) ISSN: Issue 6, Volume 2 (June 215) ACKNOWLEDGMENT We wis to aknowledge te efforts and ontributions of te anellors of Landmark University Omu-Aran, Kwara State, Bisop David Oyedepo (P.D) and Afe-Babalola University, Ado-Ekiti, Ekiti State, Afe Babalola (SAN) for teir ommitment in uman apital development via prourement of laboratory equipment and training of teir staffs wi is evidene in tis work. We will forever remain indebted to tem. To God alone be all te glory. REFERENCES [1]. Ci-Cuan W, Cang-Tsair C. (212): Heat and mass transfer for plate fin-and-tube eat exangers, wit and witout ydropili oating. International Journal of Heat and Mass Transfer, Volume 41, Issue 2, Pages Retrieved 6 t September,214. [2]. Sa R.K and Kandilkar S. G (1989): Te influene of te number of termal plates on plate eat exanger performane, Journal of Heat Transfer, vol.111, pp [3]. Ho-Ming Ye, (21)Effet of External Reyle on te Performane in Parallel-Flow Retangular Heat-Exangers, Tamkang Journal of Siene and Engineering, 13 ( 4) [4]. Kevin M. L (1998): Inreasing Heat Exanger Performane, Bryan Resear and Engineering, In. - Tenial Papers (Mar 1998), Vol 2. [5]. Dardour, S. Mazouz, and Bellagi A( 29): Numerial Analysis of Plate Heat Exanger Performane in CoCurrent Fluid Flow Configuration, World Aademy of Siene, Engineering and Tenology, Vol: 3, [6]. Murugesan M.P. and Balasubramanian R.(213): To Study te Fouling of Corrugated Plate Type Heat Exanger in te Dairy Industry, Resear Journal of Engineering Sienes, Vol. 2(1), 5-1, [7]. Murugesan M.P. and Balasubramanian R., Te Experimental Study on Enanged eat Transfer Performane in Plate Type Heat Exanger, Resear Journal of Engineering Sienes, Vol. 2(2), 16-22, [8]. Sadeva R.C (28): Fundamentals of Engineering Heat and Mass Transfer, New age International Publisers, pp [9]. Sanviente E. et al (212): Transitional Natural Convetion Flow and Heat Transfer in an Open Cannel: International Journal of Termal Siene, Pg Doi.1.116j.ijlermalsi [1]. Sai K T., Rajasekar S. G and Pravarakya G (213): Design and Analysis of Plate Heat Exanger wit CO and R134a as Working Fluids, International Journal of Meanial Engineering And Tenology, Volume 4, Issue4 [11]. Yunus A.C (23): Heat Transfer: A pratial Approa. 2 nd Ed. MGrawHill, New York , IJIRAE- All Rigts Reserved Page -23