Computer Aided Design CFD Analysis of Plate Heat Exchanger Dnyaneshwar B.Sapkal 1, Samir J.Deshmukh 2, Rucha R. Kolhekar

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1 Volume, Secial Issue 1 MEPCON 015 Available online at International Journal of Innovative and Emerging Research in Engineering e-issn: ISSN: Comuter Aided Design CFD Analysis of Plate Heat Exchanger Dnyaneshwar B.Sakal 1, Samir J.Deshmukh, Rucha R. Kolhekar 1 Student of Second year M.E.(CAD/CAM.) PRMIT &R Badnera, Amravati(M.S.) Associate Professor Mechanical Engineering Deartment PRMIT&R Badnera, Amravati (M.S) Assistant Professor Mechanical Engineering Deartment PRMIT&R Badnera, Amravati (M.S) 1 sakaldb@gmail.com, aryasamir@rediffmail.com, 3 ruchakolhekar@gmail.com ABSTRACT: An industrial alication of late heat exchangers is demonstrating a large dominance over the shell and tube heat exchangers. In this aer focus on the modeling a coer late heat exchanger for milk asteurization in a food industry using high temerature for a short time. The efficiency of the late heat exchange deends on numerous factors like sace requirement, material required for construction, ressure dro and energy requirement for circulation of milk and water by using um. This aer resents theoretical analysis of counter flow coer late tye heat exchanger and CFD analysis of ressure dro for milk and water over late heat exchanger. The results of ANSYS validate results redicted theoretically. Knowing the hot and cold fluid stream inlet and outlet temeratures and mass flow rates of hot and cold fluid and resective heat caacities, and values of heat transfer coefficient. Mathematical model based on steady flow energy. Balancing for secific heat exchanger geometry and oerational arameters the roblem first theoretically solved by LMTD method. This aer, resent modeling done by PROE, and the software analysis rediction of ressure dro analysis of late heat exchanger done by CFD tools. CFD rediction are also validate with theoretical analysis of late heat exchanger. Keywords: Plate heat Exchanger, CFD, PROE, PHE, and LMTD. I. INTRODUCTION A Heat exchanger is secialized device that assist the heat transfer of one fluid to other, in some cases a solid wall may searates the fluid and revent them from mixing. In other Design the fluid may direct contact with each other. Plates or baffle fines are from time to time used with wall in order to increase surface area turbulence introduced. A common aliance containing heat exchanger includes air conditioner, refrigerator and sace heater. A late heat exchanger also used in food industry, rocessing industry, etroleum refinery, sewage treatments shiment, sace heating chemical rocessing and ower roduction, erhas most commonly known heat exchanger is car radiator which cools the hot radiator fluid by taking advantage of air flow over a surface of radiator, there are three rimarily flow arrangements with heat exchanger counter flow, arallel flow and cross flow. The counter flow heat exchanger is more effective and efficient design because the fluid flows in oosite sides. [] In order to select suitable heat exchanger, even though the cost is often first consideration criterion evaluated and other several imortant selection criteria which includes ressure dro across heat exchanger [6], roduct mix, fluid flow, material required for construction,thermal erformance, high/low ressure limit, clean ability, maintenance and reair etc. Rates of heat flow at any oints deends uon heat transfer coefficient, temerature difference between hot fluid and cold fluid, material, No. of lates, total heat transfer area of lates. The main objectives of this resent aer theoretically analysis of coer late heat exchanger, which more referable over existing heat exchanger having stainless steel and economical also we comare volume required, material reduction, energy saving, and also ressure dros for milk and water. The result rediction ressure dro theoretically comare with CFD result. II. DESIGN METHODOLOGY The goal of heat exchanger design is to relate the inlet and outlet temeratures, the overall heat transfer coefficient, and the geometry of the heat exchanger, to the rate of heat transfer between the two fluids. The two most common heat exchanger design roblems are those of rating and sizing. The design of a two fluid heat exchanger used for the uroses of food asteurization. [1] 88

2 International Journal of Innovative and Emerging Research in Engineering Volume, Secial Issue 1 MEPCON 015 Q mc ( T T ) and C PC C1 C Q mc ( T T ) H PH H H1 Now from energy conservation we know that Considering the tye of fluids to be handled, a first guess of the overall heat transfer Coefficient Then calculate LMTD to the some mean temerature difference by means of this relation:- T1 t T t1 LMTD T1 t ln T t1 Q C With the assumed Uo, an value of the heat total heat transfer area of late required can be calculated as T is given by relation. Q U A T O T LM = Q H = Q. Overall heat transfer coefficient ( U 0 ), t [] U h h K 0 Choose the Effective Area of the late, which includes late length, width & thickness of late. Total Material required in kg mass ( m) --- kg Calculated Pressure Dro by milk and water can be calculated by using relation, 64 V L R D D e e e m Power required for circulating milk & water P=Pressure dro ( P) x mass flow rate (m)/density (ρ) Watt. [1] Table1: Oerating Condition Content Density 3 ( kg / m ) Prandelt No. Temerature. Inlet (C) Temerature. Outlet (C) Mass-flow rate(kg/sec) Milk Water [6] w U 0, A Equiment Selection duty (Watt) Materia l Table : Secification of Plate Heat Exchanger Length Widt Sacing No.of ( ) (m) h (mm) lates (m) water ( ) milk Total ower (Watt) 008 Coer N/m² 546 N/m² 37 Fig 1: Cad model of late heat exchanger Fig : Side view of Cad model 89

3 Volume, Secial Issue 1 MEPCON 015 Fig3: Imort Geometry Fig 4: Mesh model Table 3: Mesh Information CFX Domain Nodes Elements Milk Water All domain Table 4 : Boundary Condition Boundary Physics for CFX Default Domain Setting Boundary Inlet Milk Flow Regime = Subsonic Tye INLET Mass And Momentum = Normal Seed Normal Seed = [m s^- 1] Location Inlet Milk Static Temerature = 4 [C] Boundary outlet Milk Flow Regime = Subsonic Tye OUTLET Mass And Momentum - Pressure & Direction Oening Relative Pressure = 0 [Pa] Heat Transfer = Oening Oening Temerature = 80 Temerature [C] Boundary Inlet Water Flow Regime Subsonic Tye INLET Mass And Momentum - Normal Seed Normal Seed = [m s^-1] Location inlet Water Boundary Outlet Water Tye OUTLET Pressure & Direction Location Outlet Water Heat Transfer = Static Temerature Flow Regime - Subsonic Mass And Momentum - Oening Relative Pressure = 0 [Pa Oening Temerature = 65 [C] Fig 5: Boundary tye and Location 90

4 Volume, Secial Issue 1 MEPCON 015 III. NOMENCLATURE Symbol Name Units U 0 Overall heat transfer coefficient. h Convective heat transfer coefficient m h Convective heat transfer coefficient w K Thermal conductivity of material t W m thickness of late of late Mm Density of fluid T LM Logarithmic Mean tem. Difference C [] 3 ( kg / m ) IV. CFD RESULT AND DISCUSSION Zones Blue Values in Pa. 9.78e+00 1 Fig 6 : Pressure dro variation over the Water late Discussion Shows very low ressure is created at the outlet section due to Extraction of heat with low velocity flow Skyblue 1.94e+00 Shows the ressure create on thoughts the water lates Green 3.395e+00 Its shows the little high ressure occurred at the water flow side Yellow 4.364e+00 Shows the little high ressure occurred at middle section of water lates Red 5.817e+00 Shows the maximum ressure occurred at the inlet of water because due to high velocity value Fig 6 : Pressure dro variation of Milk over late 91

5 Volume, Secial Issue 1 MEPCON 015 Zones Value in Pa. Discussion Blue 1.001e+00 Shows the very low ressure at the water outlet section due to extraction of heat with low flow velocity Sky- Blue.78e+00 Shows the ressure create on throughout milk late. Red Shows maximum ressure occurred at the inlet of water because due to high velocity value Results Analytical CFD Pressure dro for milk (N/m²) Pressure dro for water (N/m²) V. CONCLUSIONS 1. It is concluded that the results obtained the total volume in use by the M.S. material late heat exchanger is 0.153m³, while the volume of the coer late heat exchanger is 0.071m³ using of coer material. Coer late tye heat exchanger results in an 8.16 % diminution in volume relative to the existing late M.S. late heat exchanger.. Material required for the coer late heat Exchanger is 4.5 Kg but M.S. late heat exchanger is required Kg. reduction material required for construction coer material late heat exchanger. 3. The ressure dro related with the use of coer late heat exchanger are considerably less than for conventional concentric tube configuration and the stainless late heat exchanger i.e. low ower consumtion. 4. For circulating milk and water for stainless steel late exchanger, the total ower required 105 Watt, the annual units required for circulating is 914 units. A coer material of late heat exchanger required the total ower 37 Watt, the annual units required only 35 units. 5. The CFD outcome of ressure dro is low as comare to the analytical result, we save energy require for circulation of water & milk is very low as comare to the stainless steel due to the above oints hence refer coer model of late heat exchanger. This is an attemt to validate the CFD rediction with that of the analytical result. REFERENCES [1] Frank P. Incroera, David P. Dewitt, Adrienne S. Lavine, Theodore L. Bergman A textbook of Fundamentals of Heat and mass Transfer Sixth Edition toic Heat Exchanger Analysis Page no.683 [] R.K. Rajut A text book of Heat and Mass Transfer Toic Heat Exchanger , [3] Numerical Analysis of Plate Heat Exchanger Performance in Co-Current Fluid Flow By H. Dardour, S. Mazouz, and A. Bellagi World Academy of Science, Engineering and Technology Vol: Configuration [4] Dr.R.K. Bansal A text book of Fluid Mechanics and Hydraulic Machines, First Edition, Laxmi Publication (P) Ltd,. 1-6, ,56-8, [5] Ahmetbaylar,M. Cihanaydin, Mehmet unsaland Fahriozkan, Numericalmodeling of heatexchangfor determining heat flow rates using fluent v 6.. Vol. No., , 009. [6] C.B. Prajaati, V.K.Patel, S.N. Singh V.Seshadri. CFD analysis of ermanent ressure loss for different tyes of flow meters in industrial alications, 37 th National and 4 th International conference of fluid mechanics & fluid ower, dec-16-18, 010 At IIT Madras [7] B. Aacoglu S. Aradag, CFD analysis of uncontrolled and controlled turbulent flow over a circular cylinder.16- May 011, Elazıg, Turkey [8] Gut,J. A W.& Pinto, J. M.(003)Modeling of late heat exchangers with generalized configurations, International Journal of Heat and Mass Transfer, , ISSN: