ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-472-4
ISBN Online: 978-1-56700-471-7
3rd Thermal and Fluids Engineering Conference (TFEC)
TAB-INDUCED COUNTER-ROTATING VORTEX PAIRS FOR MIXING AND HEAT TRANSFER APPLICATIONS
Аннотация
One of the common passive methods to enhance heat transfer with low pressure drop is the use of vortex
generators (VGs). In the present study, an experimental investigation was carried out to explore the effects of
single vortex generators on flow dynamics and heat transfer when using air as heat transfer fluid. Mean
velocities and surface temperature distributions have been characterized by using particle image velocimetry
(PIV) and infrared camera thermography at a fixed Reynolds number of air (Re = 4800). Physical parameters
of vortex generators, such as inclination angle and taper angle, were varied to understand the role of VG
geometry on flow and heat transfer characteristics. Results to date show that taper angle and inclination
angle have distinct effects on local heat transfer behavior. Specifically, the induced counter-rotating vortex
pair (CVP) leads to heat transfer enhancement both along the streamwise and spanwise directions. Better
cooling effects are found in the down-flow regions due to the acceleration of streamwise velocity in those
regions. In general, the effects by the CVP structures on convective heat transfer are evident in the range of
x/h < 1.5 - 2 approximately. Results also show that heat transfer enhancement can be correlated directly to
the local shear rate at the wall. The results also suggest that the heat transfer rates on the surface depend
mainly on flow resistance near the heated wall.