THREE DIMENSIONAL NUMERICAL ANALYSIS OF HEAT TRANSFER BY FORCED CONVECTION THROUGH HEAT SINK WITH RECTANGULAR RIBS
1 student Mechanical, MIT College 2 Assistant professor Mechanical, MIT College Abstract— Numerical simulation of heat transfer in the rectangular fin type of heat sink has been made under various operating conditions. Commercially available software package Ansys Fluent is used for the purpose. The methodology is validated by analyzing the flow through rectangular channel with heat transfer. The computed result is compared with the standard available data and it is concluded that „k-ω‟ turbulence model gives best element in case of turbulence flow. In the present study the methodology has been validated by CFD then it is used to analyse the heat transfer characteristics of plate fins with rectangular ribs. Analysis have been made for various dimensions and spacing of the ribs. It is observed that the introduction ribs enhance the heat transfer capabilities. They effect of flow velocities on Nusselt number at various rib length(0.2mm,0.3mm,0.4mm, and 0.5mm) as well as diagonal pitches(1.25mm,1.5mm,1.75mm, and 2mm) have been quantitevely analyzed. The analysis shown that rib length 0.5mm and diagonal pitch 1.25mm gives the highest enhancement in the heat transfer. The provisional of ribs also result in increases in the pressure drop through the passage. Hence it is necessary to optimize both heat transfer co-efficient and pressure drop simultaneously. Keywords—CFD, Rectangular ribs, pressure drop, Nusselt number, Friction factor.