Prediction of surface heating effect on non-equilibrium homogeneous condensation in supersonic nozzle using CFD method

Abstract

To get better industrial equipment, one must understand the different phenomena within a machine. Non-equilibrium condensation is one of the natural phenomena happening in the process, thereby affecting flow behavior; the concept is vital in the understanding and optimizing machinery applied in industries. The present investigation focuses on the surface heating method, more precisely using the constant heat flux in the context of NEC inside a supersonic nozzle. The results indicate that the heat flux method can delay the droplet nucleation and growth inside the nozzle. However, this should be considered to a limit due to the raise of temperature at the nozzle wall. The rise in heat flux has reduced the Liquid Mass Fraction (LMF) within the nozzle. The LMF at the nozzle outlet and center line is determined to be 0.075, 0.072, and 0.068 for the adiabatic condition, 200 kW/m2 flux, and 400 kW/m2 flux, respectively. The heat flux also influences the flow pattern. With an increase in heat flux, the condensation shock wave is shifted downstream, decreasing its intensity.