A preconditioned Navier-Stokes method for two-phase flows with applicationto cavitation prediction

An implicit algorithm for the computation of viscous two-phase flows is pre sented in this paper. The baseline differential equation system is the mult i-phase Navier-Stokes equations, comprised of the mixture volume, mixture m omentum and constituent volume fraction equations. Though further generaliz ation is straightforward, a three-species formulation is pursued here, whic h separately accounts for the liquid and vapor (which exchange mass) as wel l as a non-condensable gas field. The implicit method developed here employ s a dual-time, preconditioned, three-dimensional algorithm, with multiblock and parallel execution capabilities. Time-derivative preconditioning is em ployed to ensure well-conditioned eigenvalues, which is important for the c omputational efficiency of the method. Special care is taken to ensure that the resulting eigensystem is independent of the density ratio and the loca l volume fraction, which renders the scheme well-suited to high density rat io, phase-separated two-fluid flows characteristic of many cavitating and b oiling systems. To demonstrate the capabilities of the scheme, several two- and three-dimensional examples are presented. (C) 2000 Elsevier Science Lt d. All rights reserved.