The Role of Fin Geometry in Heat Sink Performance

The following study will examine the effect on overall thermal/fluid performance associated with different fin geometries, including, rectangular plates as well as square, circular and elliptical pin fins. The use of EGM allows the combined effect of thermal resistance and pressure drop to be assessed through the simultaneous interaction with the heat sink. A general expression for the entropy generation rate is obtained by using the conservations equations for mass, energy, and entropy. The formulation for the dimensionless entropy generation rate is developed in terms of dimensionless variables, including the aspect ratio, Reynolds number, Nusselt number and the drag coefficient. Selected fin geometries are examined for the minimum entropy generation rate corresponding to different parameters including axis ratio, aspect ratio, and approach velocity. The results clearly indicate that the preferred fin profile is very dependent on these parameters.