A hybrid RANS/LES framework to investigate spatially developing turbulent boundary layers

TL;DR

This paper introduces a hybrid RANS/LES modeling framework combining IDDES with a recycling/rescaling inflow turbulence method, applied to turbulent boundary layers, showing good agreement with experimental data and highlighting areas for near-wall model improvement.

Contribution

A novel hybrid RANS/LES framework integrating IDDES with a recycling/rescaling inflow method for boundary layer simulations.

Findings

Good agreement with experimental mean velocity and skin friction data.

Reynolds stress trends are correctly captured.

Near-wall shear stress distribution shows room for model enhancement.

Abstract

A hybrid RANS/LES framework is developed based on a recently proposed Improved Delayed Detached Eddy Simulation (IDDES) model combined with a variant of recycling and rescaling method of generating inflow turbulence. This framework was applied to investigate spatially developing flat plate turbulent boundary layer up to momentum thickness Reynolds number, $R_{\theta} = 31000$ and the results are compared with the available experimental data. Good agreement was obtained for the global quantities such as mean velocity and skin friction at all momentum thickness Reynolds numbers considered. The trends obtained for the Reynolds stress components are in the right direction. At high $R_{\theta$}, the shear stress distribution shows significant differences close to the wall indicating scope for further improving the near-wall modeling in such methods.