DIRECT NUMERICAL SIMULATION OF TURBULENT FLOW WITH SUPERCRITICAL FLUID IN A HEATED PIPE

Abstract

This work investigates turbulent heat transfer to a pipe flow with a fluid close to its vapour-liquid critical point. The flow is simulated using Direct Numerical Simulations (DNS) of the anelastic Navier-Stokes equations at a Reynolds number of Ret = 360, based on the friction velocity ut at the inlet and the diameter of the pipe. Turbulent statistics for two cases with forced and mixed convection are discussed. A decrease in turbulent kinetic energy is observed for both cases due to flow acceleration and buoyancy effects. Furthermore it is observed that the correlation between turbulent heat flux and Reynolds stresses is lower than in subcritical flows.