Thermal Analysis of Flow Across Two Tandem Triangular Bluff Bodies in Unsteady Regime

Abstract

AbstractThermal behavior of flow across sharp edge bluff bodies (such as rectangular, triangular bluff bodies, etc.) is repeatedly used for the designing of novel heat exchange systems, support structures, impellers, etc. However, the triangular bluff bodies are primarily studied for their use in the designing, construction, and working of a vortex flow meter. Thus, the present paper focuses on the two-dimensional transfer of heat by forced convection by the flow of Newtonian fluid around two isothermal tandem isosceles triangular bluff bodies placed in a horizontal channel with adiabatic walls. The effect of gap space (i.e., gap between two triangular bluff bodies) ranging from 1 to 4 for Prandtl number of 0.71 (air) and Reynolds number of 100 is investigated, by keeping the blockage ratio fixed as 25%. Simulation of the present problem is carried out by solving governing equations, i.e., equation for conservation of mass, conservation of momentum, and conservation of energy, along with suitable boundary conditions with the SIMPLE method by using a finite volume-based solver. Contours of streamline and isotherms help in understanding the flow and temperature fields across the two triangular cylinders, respectively. The average Nusselt number, mean drag coefficient, etc., are calculated. It is found that the values of the average Nusselt number and the mean drag coefficient, both, decline with the declining gap space between the two tandem bluff bodies. The changes in the average Nusselt number and mean drag coefficient values are more significant for the second triangular bluff body than the first one.KeywordsTriangular bluff bodyCFDThermal analysis