Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 0-89116-299-2

International Heat Transfer Conference 7
September, 6-10, 1982, Munich, Germany

HEAT TRANSFER IN A TURBULENT BOUNDARY LAYER BEHIND A TWO-DIMENSIONAL BLUFF BODY AT DIFFERENT Pr NUMBERS

Get access (open in a dialog) DOI: 10.1615/IHTC7.1740
pages 217-221

Abstrakt

Measurements downstream of an obstacle in fluids of different Pr suggest that maximum disturbances in the sublayer do not coincide with maximum turbulence in the shear layer along the reattachment region. Unlike the case of Pr = 1, for higher obstacles and Pr >> l, an upstream shift of the maximum heat transfer is observed. The length of the separation region l reflects the intensity of reattachment. With a reference to this, Nul ~ Rel·R0−0.2 for Pr = 1. In the region of redevelopment, there exist two distinct stages of return to the ordinary heat transfer, with a significant effect of the turbulence memory. In the first stage of relaxation L = 0.4x. A neglect of the memory effect leads to overestimated values of the turbulent Prandtl number.