Performance analysis of heat exchanger with different types of fins

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1 1. International Engineering Reearch Journal (IERJ) Special Iue 3 Page 3-370, 201, ISSN ISSN Performance analyi of heat exchanger with different type of fin #1 Mi. Priyanka Ghurde, #2 Prof. S.P.Yeole 1 priyanka.ghurde21@gmail.com 2 rkpvpit@gmail.com #12 Mechanical Department, SGBAUniverity, P.R.Pote college of engineering, Amravati, Sant Gadge baba Amravati Univerity, Pincode: ABSTRACT ARTICLE INFO Variou method are ued to increae rate of heat tranfer without affecting much the overall performance of the ytem. Thee technique are ued in heat exchanger. Heat exchanger i ued in variou application in day to day life. Some of the application of heat exchanger are in proce indutrie, thermal power plant, air conditioning equipment, refrigerator, radiator for pace vehicle, automobile etc. The preent paper i review of the variou method ued to increae the heat tranfer performance by uing different type of fin. The performance of different fin type i evaluated at different Reynold number, fin pitch, number of tube row etc. Keyword heat exchanger, fin. I. INTRODUCTION The rate of heat tranfer from a urface at a temperature T to the urrounding medium at Ti given by Newton law of cooling a, Q conv= ha (T-T ) Article Hitory Received :29 th February 201 Received in revied form : 1 t March 201 Accepted : 4 th March 201 Publihed online : th March 201 packed thin metal heet attached to the hot-water tube increae the urface area for convection and thu the rate of convection heat tranfer from the tube to the air many time. There are a variety of innovative fin deign available in the market. Where, A i the heat tranfer urface area and h i the convection heat tranfer coefficient. When the temperature T and Tare fixed by deign conideration, a i often the cae, there are two way to increae the rate of heat tranfer: to increae the convection heat tranfer coefficient h or to increae the urface area A. Increaing h may require the intallation of a pump or fan, or replacing the exiting one with a larger one, but thi approach may or may not be practical. Beide, it may not be adequate. The alternative i to increae the urface area by attaching to the urface extended urface called fin made of highly conductive material uch a aluminium. Finned urface are manufactured by extruding, welding, or wrapping a thin metal heet on a urface. Fin enhance heat tranfer from a urface by expoing a larger urface area to convection and radiation. Finned urface are commonly ued in practice to enhance heat tranfer, and they often increae the rate of heat tranfer from a urface everal fold. The car radiator hown in Fig i an example of a finned urface. The cloely Figure 1: Some innovative fin deign. 2015, IERJ All Right Reerved Page 1

2 International Engineering Reearch Journal (IERJ) Special Iue 3 Page 3-370, 201, ISSN and ingle wall interruption. FLUENT and COMSOL metaphyic oftware are ued in order to develop a two dimenional numerical model for invetigation of fin interruption effect. Ue of adding interruption to vertical fin increae the thermal performance and reduce the weight of the fin array, can lead to lower manufacturing cot. Figure 2: The thin plate fin of a car radiator greatly increae the rate of heat tranfer to the air. II. LITERATURE REVIEW The literature review mainly focuing on deign and optimization technique baed on analyi of heat exchanger with different type of fin and their reearch and outcome. The detail of literature review have been i a follow. 2.1 Abdullah, H. Alea et. al. Had tudied the natural convection heat tranfer enhancement from rectangular fin embedded with equilateral triangular perforation. The heat diipation rate from the perforated fin i compared to that equivalent olid one. The effect of geometrical dimenion of the perforated fin and thermal propertie of the fin wa tudied in detail. They concluded that, heat tranfer rate of perforated fin can be enhancement for certain valve of triangular dimenion. The magnitude of enhancement i proportional to the fin thickne and it thermal conductivity. The magnitude of enhancement i proportional to the fin thickne and it thermal conductivity. The perforation of fin enhance heat diipation rate and at the ame time decreae the expenditure of the fin material. 2.2 B. Ramda Pradip et. al. Had tudied thermal ytem in many indutrie wherein overheating can damage the ytem component and lead to failure of the ytem. In order to overcome thi problem, thermal ytem with effective emitter uch a rib, fin, baffle etc. are deirable. The need to increae the thermal performance of the ytem, thereby affecting energy, material and cot aving ha led to development and ue of many technique termed a Heat tranfer Augmentation. Thi technique i alo termed a Heat tranfer Enhancement or Intenification. Due to Augmentation technique increae convective heat tranfer by reducing thermal reitance in heat exchanger. There are many augmentation technique (a) urface roughne, (b) plate baffle and wave baffle, (c) perforated baffle, (d) inclined baffle, (e) porou baffle, (f) corrugated channel, (g) twited tape inert, (h) dicontinuou Croed Rib and Groove. Ue of Heat tranfer enhancement technique lead to increae in heat tranfer coefficient but at the cot of increae in preure drop. 2.3 Golnooh Motafavi had invetigated the teady-tate external natural convection heat tranfer from vertically mounted rectangular interrupted finned heat ink. After regenerating and validating the exiting analytical reult for continuou fin a ytematic numerical, experimental, and analytical tudy i conducted on the effect of the fin array 2.4 Sable, M.J. et. al. had invetigated for natural convection adjacent to a vertical heated plate with a multiple v- type partition plate (fin) in ambient air urrounding. V- type partition plate work not only a extended urface but alo a flow tabulator a compare to conventional vertical fin, In order to enhance the heat tranfer, V-haped partition fin with edge faced uptream were attached to the two identical vertical plate. They oberved that among the three different fin array configuration on vertical heated plate, V-type fin array deign perform better than rectangular vertical fin array with bottom pacing deign. The performance wa oberved to improve further, with increae in the height of the V-fin height. momentum and energy to individual operation of manifold, mixing chamber and cylinder. Two different approache ued to develop two model are preented. The effect of motive team preure, evaporator temperature, and preure rie acro the manifold, and the reult preented. To tet the adequacy of the model, thee reult were compared with empirical graph and are found to be in good agreement. III. DESIGN ANALYSIS OF FIN WITH EXTENSIONS A. Deigning of AutoCAD The fin with variou are deign with the help of deign oftware AutoCAD by uing the AutoCAD 2D and 3D command like a 2D command polyline, arc, mirror, pedit,& 3D command extrude. The line draw with the Polar mode. In thi mode length of the line and angle of the line i defined to draw the deign. [5] The angle i meaured in anti-clock direction tarting from the firt quadrant. Main Fin pecification: Length, l = 40mm = 0.04 m, width, b = 240 mm = 0.24 m and thickne, y = 15mm = m. Specification of variou hown in the Fig. 3 and number of ued on main fin i 10 no. Figure 3: (a) Rectangular extenion, (b) Trapezium extenion, (c) Triangular extenion, (d) Circular extenion. B. Analyi of fin for Heat Tranfer with Any oftware 2015, IERJ All Right Reerved Page 2

3 International Engineering Reearch Journal (IERJ) Special Iue 3 Page 3-370, 201, ISSN The numerical analyi ha been carried out for computing the temperature and thermal tre ditribution in fin uing commercially available finite element oftware ANSYS. The cutom ytem option for thermal analyi wa elected. The numerical analyi wa baed on the following aumption I) Steady-tate heat flow, II) The material are homogeneou and iotropic, III) The convection heat tranfer coefficient i the ame all over the urface, IV) The thermal conductivity of the material i contant In thi work we have made a model for cylinder engine uing CATIA for variou profile which include rectangular, tapered and helical. The below figure how the helical profile in a cylinder engine.similarly other profile were only changed in the above model. After the model ha been made then we aign the boundary condition baed on the paper. In thi we have taken baically 3 parameter teady tate, total heat flux and directional heat flux for all the three profile. C. Aigning Load and Contraint In thi aign the material having thermal conductivity, convection coefficient of heat tranfer for fluid, temperature of urface and ambient temperature a: Thermal conductivity, k = 40 W/m C = 0.04 J/( mm C) Convection coefficient of heat tranfer, h = 40 W/m2 C = J/( mm2 C) Temperature of wall urface at which fin attached, to = 55 C Ambient temperature, ta = 30 C (a) Similarly the reultant Fig. 5 & Fig. how that variation of temperature along length of fin with trapezium, triangular and fin with fin without that the temperature reduce from fin bae to the tip end of the fin. (b) D. Reult from the Analyi After the generation of model and aigning of load, the proce for the analying teady tate heat tranfer proce and finally obtain the required reult of temperature. Fig. 7: Temperature contour for fin (a) Circular, (b) Without. Figure 4: Show that variation of temperature along length of fin with rectangular that the temperature reduce from fin bae at 55 C to C at the tip end of the fin. Figure 8: plot howing the temperature variation along with length of fin with rectangular, trapezium, triangular, and fin without. 2015, IERJ All Right Reerved Page 3

4 International Engineering Reearch Journal (IERJ) Special Iue 3 Page 3-370, 201, ISSN IV. RESULTS AND DISCUSSIONS Heat tranfer calculated by uing the heat tranfer governing differential equation for the fin of finite length and loe heat by convection [], for which the given length of fin (l in m), thickne of fin (y in m), width of fin (b in m),thermal conductivity of fin (k in W/m C ), coefficient of convective heat tranfer (h in W/m2 C ), temperature at bae of fin (to in C),temperature of the ambient fluid (ta in C). After the calculation of heat tranfer rate of variou fin geometry now it i the time to compare the increae in heat tranfer rate for the given geometry of fin which i hown in Table-2. The fin without having W heat tranfer value. TABLE-1 COMPARISON OF HEAT TRANSFER FOR VARIOUS EXTENSIONS ON FIN. rectangular trapezium triangular Heat tranfer (in W) Increae in heat tranfer (in W) Percentage increae in heat tranfer (in percentage) TABLE-3 HEAT TRANSFER THROUGH FIN AT AMBIENT TEMPERATURE 28 C TO 18 C Type of extenio n Rectangu lar Trapeziu m Triangula r egmenta l Qfin in W at ambient temperature 28 0 C 2 0 C 24 0 C 22 0 C 20 0 C 18 0 C Without extenion 0 TABLE-4 PERCENTAGE INCREASE IN HEAT TRANSFER FIN WITH EXTENSIONS Rectangul ar Trapezium Triangular Percentage increae in heat tranfer fin with 28 0 C 2 0 C 24 0 C 22 0 C 20 0 C 18 0 C TABLE-5 EFFECTIVENESS OF FIN WITH EXTENSIONS Rectangul ar Trapezium Triangular Effectivene C 2 0 C 24 0 C 22 0 C 20 0 C 18 0 C V. CONCLUSION The ue of fin (extended urface) with, provide efficient heat tranfer: provide near about 5 % to 13% more enhancement of heat tranfer a compare to fin without. Heat tranfer through fin with rectangular higher than that of fin with other type of. Temperature at the end of fin with rectangular i minimum a compare to fin with other type of. The effectivene of fin with rectangular i greater than other. Chooing the minimum value of ambient fluid temperature provide the greater heat tranfer rate enhancement. REFERENCES [1]. Abdullah, H. Alea and Mohammed, Q. Al-Odat, Enhancement of Natural Convection Heat Tranfer from a Fin by Triangular Perforation of Bae Parallel and Toward it Bae, the Arabian Journal for Science and Engineering, vol. 34, pp , [2]. B. Ramda, Pradip and K. Kumar, Dineh, A Study on the Heat Tranfer Enhancement for Air Flow through a Duct with Variou Rib Inert, International Journal of Latet Trend in Engineering and Technology, vol. 2, iue 4, pp , , IERJ All Right Reerved Page 4

5 International Engineering Reearch Journal (IERJ) Special Iue 3 Page 3-370, 201, ISSN [3]. Golnooh Motafavi, Natural Convective Heat Tranfer from Interrupted Rectangular Fin, MASc, Simon Fraer Univerity, Canada, [4]. Sable M.J., Jagtap S.J., Patil P.S., Bavikar P.R. and Barve S.B., Enhancement of Natural Convection Heat Tranfer on Vertical Heated Plate by Multiple V-fin array, IJRRAS, vol. 5, iue 2, pp , [5]. Vihal S., Auto-CAD, Dhanpat Rai Pubblicating Company, New Delhi, pp , []. Rajput R. K., Heat and Ma Tranfer, S. Chand & Company Ltd., New Delhi, , IERJ All Right Reerved Page 5