Simulation of Homogeneous Condensation of Ethanol in High Pressure Supersonic Nozzle Flows using BGK Condensation Model

In the present work, we have simulated the homogeneous condensation flow of ethanol using the Bhatnagar-Gross-Krook (BGK) based condensation model for the experimental conditions of Wegener et al. [1]. In an earlier work carried out by Gallagher-Rogers et al. [2], it was found not possible to simulate the experimental conditions using the direct simulation Monte-Carlo (DSMC) based condensation model. In this work we use a statistical-BGK approach to model condensation and compare our simulated predictions of the point of condensation onset and the distribution of mass fraction along the nozzle centerline with experiments. The experiments provide data for different cases corresponding to varying amounts of ethanol concentration, compared to air, for total mixture pressures which remains mostly constant for all cases. Our numerical results show good agreement with the experiments, thus validating our BGK based condensation model for high pressure flow applications.