Interphase processes analysis in moist air transonic flows in nozzles

Abstract

During the flow of atmospheric air through convergent-divergent (CD) nozzles the water vapour contained in it can condense spontaneously. The resulting liquid phase may then undergo further phase transitions, e.g. evaporation on the shock waves arising in the nozzle divergent part. The subject of this paper is a numerical and experimental analysis of the process of atmospheric air water vapour condensation and an analysis of the resulting liquid phase evaporation on the shock wave. Calculations are performed using an in-house CFD code based on the solution of averaged Navier-Stokes equations supplemented with additional equations modelling the condensation process of water vapour contained in atmospheric air. Experiments are carried out using an in-house facility adapted for measurements of atmospheric air transonic flows. KEYWORDS MOIST AIR, CONDENSATION, EVAPORATION NOMENCLATURE c speed of sound cp specific heat at constant pressure D32 Sauter mean diameter h specific enthalpy L latent heat M Mach Number m mass p pressure s specific entropy T temperature u velocity y wetness mass fraction ΔT temperature increment  relative humidity Subscripts 0 total parameters 1, 2, 3, 4 characteristic points l liquid