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Numerical experiments have been presently conducted aiming at studying the influence of the surface energy on the crystallization process of supercooled water in terms of the supercooling degrees. The mathematical model consists primarily of the equation governing the thermal energy field solved independently in both phases in accordance with the two-scalar approach by utilizing the Stefan condition at the interface to couple both temperature fields. The computational algorithm relying on the level-set method for solid-liquid interface capturing has been appropriately upgraded aiming at accuracy level increase with respect to the discretization of the thermal energy equation and the normal-to-interface derivative of the temperature field. The model describes the freezing mechanism under supercooled conditions, relying on the physical and mathematical description of the two-phase moving-boundary approach.

A computational study of the vehicle aerodynamics influenced by the wake of the rotating wheel taking into account a detailed rim geometry is presently performed. The car configuration corresponds to a full-scale (1:1) notchback configuration of the well-known ‘DrivAer’ vehicle model, Heft et al. [1]. The objective of the present work is to investigate the performance of some popular turbulence models in conjunction with different methods for handling the wheel rotation – rotating wall velocity, ‘multiple reference frame’ and ‘sliding grid algorithm’. The specific focus hereby is on a near-wall RANS eddy-viscosity model based on elliptic-relaxation, sensitized to resolve fluctuating turbulence by introducing a specifically modeled production term in the scale-supplying equation, motivated by the Scale-Adaptive Simulation approach (SAS, [2]), proposed by Krumbein et al. [3].