Numerical Simulation of inser‎ts Effect on Heat Transfer and Pressure dro‎p in a 3D Laminar and Turbulent flow in Tube with k 2 f Model Mohammad Reza Nazari mnazari@yazduni ac ir 2009 1 28 Department of Mechanical Eng Isfahan University of Technology Isfahan 84156 83111 IranA A Alemrajabi rajabi@cc iut ac irE ShiranaiA SohankarM KeshmiriABSTRACTHeat transfer and pressure drop for a 3D flow in a pipe which is equipped with one or fewinserts is numerically investigated The Reynolds number for the flow ranges between 450to 1800 for laminar and 3000 to 45000 for turbulent flow and the Prandtle number is 0 72 In laminar flow inserts are inter connected by a thin rod and kept in the center of the pipe In turbulent flow inserts are connected to the wall The number of inserts the distancebetween them and their axial length are the variables and their effects on the heat transferand pressure drop are investigated Finite volume method is employed to transfer thegovening equations into algebraic ones To eva‎lutae simultaneous effect of inserts on heattransfer and pressure drop an overall enhanncement ratio OER is introduced and applied The results show that in many cases thinner insserts lead to a better OERs Also in lamiarflow the shape of the inserts is effective on the ORE In turbulent flow longitudinalvortices near the wall more effects in heat transfer Key Words heat transfer enhancement pressure drop numerical method tube inserts

علي اكبر عالم رجبي

ابراهيم شيراني، احمد سوهانكار

محمود يعقوبي، محمد حسن سعيدي، محمود اشرفي زاده، محسن دوازده امامي، محمد رضا سليم پور