LES of an Asymmetrically Heated High Aspect Ratio Duct at High Reynolds Number at Different Wall Temperatures

We present the results of well-resolved large-eddy simulations (LES) of an asymmetrically heated high aspect ratio cooling duct (HARCD) with an aspect ratio of AR = 4.3 for two different wall temperatures. The temperature difference with respect to the bulk flow is ∆T = 40 K, respectively ∆T = 60 K. The HARCD is operated with liquid water at a Reynolds number of Reb = 110 ⋅ 103 based on bulk velocity and hydraulic diameter. The generic HARCD setup follows a reference experiment. The main goal of the present study is the numerical investigation of the interaction of turbulent heat transfer and the turbulent duct flow, specifically the heating induced changes in mean flow and turbulent statistics with a spatially developing temperature boundary layer. Furthermore, we investigate the influence of asymmetric wall heating on streamwise vorticity and its dynamics as well as the turbulent Prandtl number and the effect of the secondary flow on its distribution.