Condensation models and boundary conditions for non-equilibrium wet steam flows

This paper is dedicated to the physical and numerical modelisation of wet steam flows with non-equilibrium condensation in power plant steam turbines. The steam, far from an ideal gas behavior is modeled thanks to real gas thermodynamic laws. The nucleation process is taken into ac- count using two models: a simple two-equation model and the Quadrature Method of Moments. The numerical scheme used to handle the complex thermodynamics is the approximate Riemann solver VFRoe for which a particular attention has been paid regarding the boundary conditions. Shock-tube verification test cases are given to check the good behavior of the scheme and validation cases in nozzles are presented to illustrate the accuracy of the physical model compared with experimental data.

Key words : condensation, nucleation, quadrature method of moments, droplets size distribution, real gas, VFRoe scheme, boundary conditions

Paper presented by JM Hérard and T. Gallouët on June, 26, 2013