基于熵限制的Baldwin-Lomax湍流模型

New kind Baldwin-Lomax turbulence model under the limit of entropy

针对Baldwin-Lomax(BL)模型在模拟超声速复杂流动中的不足,提出一种基于熵限制的新型修正方式.分别采用原始的BL模型(BL-origin)、修正后的BL模型(BL-entropy)以及Wilcox k-ω两方程模型对超声速平板、超声速二维压缩拐角以及膨胀-压缩拐角3个典型算例进行计算,结果表明BL-entropy能够较好地获取长度尺度进而得到均匀合理的涡粘性分布.同时,该修正方式简单高效并且适用于其他与超声速边界层有关的模型,具有较大的发展潜力.

A new kind correction to Baldwin-Lomax turbulence model （BL-entropy） based on the concept of entropy was proposed. The supersonic plane, two-dimensional supersonic compression comer and expan- sion-compression comer which were representative in the engineering area were chosen in the numerical simu- lation to evaluate the performance of this model. It is found that BL-entropy can conquer the essential deficien- cy of the original model by providing a more physically correct length scale in the supersonic complex flow. Moreover, this method is simple, eomputationally fast and general, making it applicable to other models relat- ed with the supersonic boundary layer.