一个新的可压缩性修正的k-ε模型

考虑结构可压缩性修正的影响,发展了一个同时考虑结构可压缩性修正和膨胀可压缩性修正的k-ε湍流模型,新模型包括Chang可实现性、Heinz湍流动能产生项以及Sarkar可压缩性三部分修正.新模型扩宽了以往发展的可压缩性修正模型的适用范围,适用于高超声速(M>5)复杂湍流流动中.通过对多个复杂超声速横侧射流工况的计算,验证了新模型的预测效果.与实验结果相比表明,几个工况下新模型的预测精度都显著高于标准k-ε模型.流体分离强度越大,新模型的修正效果越显著.与标准k-ε模型相比,新模型计算结果与实验更加接近.

A new k-ε turbulence model with compressibility modifications

Considering structural compressibility effect, a new k-ε turbulence model with structural compressibility and dilatational compressibility modifications was proposed. Three modifications were added to improve the standard k-ε turbulence model. They are Chang realizable, Heinz turbulence production and Sarkar dilatational compressibility correction terms. The new model was applicable in complex hypersonic flows which widens the range of the application of the previous compressibility modification model. Several complex supersonic transverse injection flows were calculated to verify the performance of the new model. Comparisons with experimental data show that the new model significantly improves the predictions than the standard k-ε model. Better results were obtained even in flows with great fluid separation and predictions of the new model were closer to the experimental data than the standard k-ε model.