Velocity transformation for compressible wall-bounded turbulent flows with and without heat transfer

TL;DR

This paper introduces a new velocity transformation that accurately maps compressible wall-bounded turbulent flow profiles to incompressible ones, working across various flow conditions and heat transfer scenarios without tuning.

Contribution

A novel, universally applicable velocity transformation for compressible turbulent flows that works across different flow regimes and heat transfer conditions without specific tuning.

Findings

Successfully collapses velocity profiles across flow types

Works without tuning for flows with heat transfer

Valid for Mach numbers 0 to 15 and Reynolds numbers 200 to 2000

Abstract

In this work, a transformation, which maps the mean velocity profiles of compressible wall-bounded turbulent flows to the incompressible law of the wall is proposed. Unlike existing approaches, the proposed transformation successfully collapses, without specific tuning, numerical simulation data from fully developed channel and pipe flows, and boundary layers with or without heat transfer. In all these cases, the transformation is successful across the entire inner layer of the boundary layer (including the viscous sublayer, buffer layer, and logarithmic layer), recovers the asymptotically exact near-wall behavior in the viscous sublayer, and is consistent with the near balance of turbulence production and dissipation in the logarithmic region of the boundary layer. The performance of the transformation is verified for compressible wall-bounded flows with edge Mach numbers ranging from 0 to 15 and friction Reynolds numbers ranging from 200 to 2000. Based on physical arguments, we show that such a general transformation exists for compressible wall-bounded turbulence regardless of the wall thermal condition.