Thermo-hydraulic effects of vortex generator pairs in a crossflow channel with a transverse-jet flow

Abstract

The use of passive obstacles to control the hydraulic and thermal behavior of fluids is an application in many industrial mechanisms. In this study, flow and thermal oscillation behaviors in a crossflow channel with a transverse jet flow were investigated numerically. Passive vortex generator(VG) pairs with different geometric properties were used in the test channel and their thermo-hydraulic effects in the active mixing zone were discussed. In addition, nine boundary conditions, which are the function of velocity and temperature, have been applied to the computational domain. The results showed that VG pairs with different geometric properties do not provide an effective improvement in thermal mixing behavior, but they are very successful in removing thermal oscillations from the channel walls. Momentum and temperature differences between cross flow and jet flow are the secondary parameters of the study. When the jet velocity was gradually increased by keeping the crossflow rate constant, improvements in thermal mixing performance were observed but in this case, it was also seen that thermal oscillations reached the channel walls. As the jet temperature increased, a decrease in thermal mixing performance was observed due to the increased hot fluid dominance in the duct.