Numerical simulation of binary-gas condensation characteristics in supersonic nozzles

摘要

Binary-gas condensation characteristics in supersonic nozzles are numerically simulated using the Euler-Euler two-fluid model with the RSM turbulence model. The effects of carrier gas, inlet pressure and inlet temperature on the distribution of the condensation parameters are analyzed. A new Laval nozzle with a central body is designed to study the effects of swirling on the condensation characteristics. The results show that the trends of the condensation parameters are substantially the same for different binary-gas systems with the same condensable gas, while the degree of supercooling, the droplet number density, the droplet radius and humidity in the nozzle are all affected by the specific heat of the carrier gas. Condensation in the nozzle can be further intensified by decreasing the inlet temperature or increasing the inlet pressure in the binary-gas system. The distribution of the condensation parameters no longer presents an axisymmetric phenomenon in Laval nozzles with swirling, and water condensation can be enhanced by increasing the swirling strength. (C) 2015 Elsevier B.V. All rights reserved.