The effect of the triangular rib usage in the plate fin heat sinks on the pressure drop, base plate temperature, and entropy generation

Abstract

Improving the thermal efficiency in plate fin heat sinks (PFHS) results in a reduction in the weight, volume and cost of the heat sink. This ensures long life and reliable operation of the cooled equipment. In this study, the performances of triangular ribbed PFHSs, which are formed by placing a staggered array of triangular ribs between plate fins, were numerically investigated. Pressure drop, base plate temperature and entropy generation are used for performance comparisons. Numerical heat transfer and flow analysis were performed in three-dimensional models with the help of Ansys Fluent program, which uses the finite volume method with incompressible, turbulent flow and conjugate heat transfer assumptions. The design parameters were determined as inlet velocity between 3 m/s and 9 m/s, number of plate fins 9, 12 and 15, plate fin heights 10 mm and 30 mm, triangular rib heights 0.1 mm and 0.3 mm. As a result, the heat sink base temperature decreases with the increase of velocity, fin height, number of plate fins and triangular rib height, lower pressure drop values were obtained in the case of Hrib=0.1 mm compared to the unribbed case. If the design with the least entropy production is desired as the optimum design, there is a %10.64 increase in the base temperature and a significant decrease in the pressure drop (220.88 Pa to 7.512 Pa). In this case, since the fin length is H=30 mm, the volume and weight of the heat sink also increase.