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

Year 2019, , 942 - 963, 01.10.2019

Beşir Kok

https://doi.org/10.16984/saufenbilder.558877

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. 

Keywords

Transverse jet, Crossflow, Thermal mixing, LES, Vortex generator

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