Study of Near Wall Coherent Flow Structures on Dimpled Surfaces Using Unsteady Pressure Measurements
- 275 Downloads
Unsteady pressure measurements have been performed inside a spherical dimple in a narrow channel for turbulent flow at Re D = 40,000 with the aim to study coherent vortex structures and to get a deep insight into flow physics. Results confirm the formation of asymmetric coherent vortex structures switching between two extreme positions. Analysis of the pressure temporal distributions and correlation functions shows the presence of the anti-phase motion inside the dimple. Typical power laws of the pressure fluctuation energy spectrum ω − 1 and ω − 7/3 are reproduced.
KeywordsDimples Vortex structures Pressure measurements
Unable to display preview. Download preview PDF.
- 1.Chyu, M.K., Yu, Y., Ding, H., Downs, J.P., Soechting, F.O.: Concavity enhanced heat transfer in an internal cooling passage. ASME No. 97-GT-437 (1997)Google Scholar
- 2.Elyyan, M.A., Rozatia, A., Tafti, D.K.: Investigation of dimpled fins for heat transfer enhancement in compact heat exchangers. Int. J. Heat Mass Transf. 51(11–12), 2950–2966 (2007)Google Scholar
- 4.Isaev, S.A., Leont’ev, A.I., Baranov, P.A., Pyshnyi, I.A.: Numerical analysis of the influence of the depth of a spherical hole on a plane wall on turbulent heat transfer. J. Eng. Phys. Thermophys. 76, 52–59 (2003)Google Scholar
- 10.Terekhov, V.I., Kalinina, S.V., Mshvidobadse, Y.M.: Heat transfer coefficient and aerodynamic resistance on a surface with a single dimple. Enhanc. Heat Transf. 4, 131–145 (1997)Google Scholar