2SFK: A TWO-FIELD RANS MODEL FOR TURBULENT FLOWS WITH HIGH DENSITY CONTRASTS; APPLICATION TO RAYLEIGH-TAYLOR TYPE INSTABILITIES

摘要

To meet our modeling needs on turbulent flows produced by gravitational instabilities, we have developed an original approach, designated as 2SFK for "two-structure, two-fluid, two-turbulent". We provide the principles of the model derivation, which hinges on averaging conditioned by the presence functions of the large structures in the flow. Numerical 1D results on the Rayleigh-Taylor instability illustrate the satisfactory behavior of the model.