DOI: 10.1615/ICHMT.2006.TurbulHeatMassTransf
ISBN Print: 978-1-56700-229-4
ISSN: 2377-2816
Role of the Sub-Kolmogorov Scales in the Near-Wall Turbulent Passive Scalar Transfer at High Prandtl Numbers
摘要
Role of the sub-Kolmogorov scales in high Prandtl number fluids is analyzed in the turbulent channel and flume flow. Temperature is assumed to be a passive scalar at Prandl numbers 100 and 200 and friction Reynolds numbers 150 and 395. Velocity field is resolved with DNS accuracy, while the temperature field is treated with LES-like approach. The present results confirm conclusions of the previous studies of Campbell and Hanratty [AIChE J. 29, 215 (1983)] and Calmet and Magnaudet [Phys. Fluids 9, 438 (1997)] and show that the near-wall heat transfer is governed by the large scale near-wall structures. Namely, the results point to the very negligible role of the sub-Kolmogorov temperature scales.