Prediction of underexpanded jets using compressibility-corrected, two-equation turbulence models

An assessment of the ability of compressibility-corrected, k-ε turbulence models to predict the characteristics of underexpanded jets is reported. A variety of compressibility modifications to the standard form of the k-ε model have been proposed; but they have rarely been tested. Modifications that range from changes to turbulence modelling constants to those that model compressibility effects on the turbulence energy dissipation rate are examined. Predictions are compared with data available for moderately and highly underexpanded jets. Overall, the models proposed by Sarkar et al. and Zeman, are found to provide the most reliable predictions of the jets examined.