Direct numerical simulation of the rotating disk turbulent boundary layer

The von Kármán turbulent boundary layer (vKTBL) induced by a rotating disk is a canonical three-dimensional turbulent boundary layer (3DTBL) that develops without a 2D precursor and exhibits unique structural features, including discrepancies between momentum and heat transfer. We present direct numerical simulations (DNS) of the vKTBL up to an azimuthal friction Reynolds number of 2300, higher than any previous DNS, enabled by a GPU-accelerated spectral element method. We also perform the first DNS of the disk’s thermal boundary layer. The results for unity Prandtl number confirm experimental observations in air of a wake component in the mean temperature profile, which is not present in the velocity profile. The DNS highlights structural similarities and differences relative to 2DTBLs, providing new insights into turbulence and scalar transport in 3DTBLs.