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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)
March, 4–7, 2018, Fort Lauderdale, FL, USA

DIRECT NUMERICAL SIMULATION OF BOUNDARY LAYER ON FLAT PLATE WITH VORTEX GENERATOR FOR HEAT TRANSFER ENHANCEMENT

Get access (open in a dialog) pages 1239-1243
DOI: 10.1615/TFEC2018.tfh.021640

Resumo

Heat transfer enhancement between gas and wall is of great importance in various fields of engineering. In this study, the heat transfer enhancement effect by vortex generators (VGs) installed in a laminar boundary layer was verified by direct numerical simulation (DNS). It should be noted that the effect of vortex gener- ators having the height of about the boundary layer thickness applied in this study has rarely been verified by means of DNS. A hemispherical, a delta-shaped and a V-shaped VGs were placed on the wall. As a result, a vortex pair was generated downstream of all the VGs. In the downstream of the delta-shaped VG, vortices were generated faster than the others. On the downstream of the hemispherical and the V-shaped VGs, the vortex is slowly generated from their shape features. The disturbance caused by the V-shaped VG is larger than those of the other VGs. The profile of the Nusselt number (Nu) averaged in the spanwise direc- tion was similar to that of the vortex pair, i.e., the increase of the averaged Nusselt number of delta-shaped VG is faster than the other VGs, and the averaged Nusselt number of the V-shaped VG is much larger than those of the others. In consequence, the averaged Nusselt numbers in the downstream of the hemispheri- cal, the delta-shaped and the V-shaped VGs were 2.6, 2.9, and 4.5 times as much as that of the flat surface, respectively.