An implicit, density-based algorithm for coupled simulations of arbitrary gas mixtures

Abstract

The development of new design concepts for cleaner and efficient propulsion and energy transformation devices (gas turbines, combined gas-steam generation groups) requires the global optimization of all machine components. In the present work a novel numerical approach is illustrated, which allows to model accurately and efficiently departures from an ideal behaviour of the working fluid in density-based solvers. The concept of residual internal energy permits a ready extension of classic flux-difference splitting or flux-splitting solution algorithms to (reacting) mixtures of thermally and calorically imperfect gases of variable composition. A fully implicit formulation is then derived in terms of mass fractions.