Author(s): Satoshi Yokojima

Linked Author(s): Satoshi Yokojima

Keywords: Turbulence model; Near-wall modeling; Separated flow

Abstract: Recently proposed turbulence models that are valid up to a wall have been critically examined by applying them to the calculation of separated and reattaching flow over a backward-facing step in an open channel. Two groups of models are considered. The first group is the widely-used k-model and the other is the k-otype model, both of which are categorized as the two-equation models. Methods of extending to the wall are either the low-Reynolds-number treatment in the near-wall region or the algebraic specification of the length scale in the same region. Detailed comparisons with a direct numerical simulation made at a low Reynolds number, and experimental data at a higher Reynolds number indicate that elaborate refinement made to fit the DNS data in simple flows is not the key to correctly predict a complex flow. A lowReynolds number variation of the k-o seems to be superior in accuracy, consistency, reliability as well as computational efficiency.

DOI:

Year: 1999