Experimental and numerical study of heat and mass transfer between high temperature supersonic gas flow and liquid water in a cylindrical duct

The mixing process of a high temperature combustion gas and liquid water conveying large amounts of heat and mass transfer in a very short period of time is investigated experimentally and numerically. A solid propellant produces hot gas into a cylindrical duct where water is supplied through water in-jectors, facilitating instantaneous mixing accompanied by evaporation and condensation along the duct. Gas generator fire tests are carried out to confirm performance. A cylindrical duct is subsequently con-nected to the rear end of the gas generator with the liquid water supply system, and experiments are performed for three different amounts of water being injected into the supersonic hot gas. A numerical scheme for a homogenous mixture model with Lee's mass transfer model is applied, and comparisons are made with the experiments. Next, both the experimental and numerical results are fairly compared. The empirical coefficients of evaporation rate for the Hertz-Knudsen-Scharage (HKS) and wall film model (WFM) equations are proposed. (c) 2021 Elsevier Ltd. All rights reserved.