可压流双方程紊流模型及其应用

 本文提出了可压流紊流模型。所用的方法类似于K-KL双方程模型,但考虑了气流压缩性的影响。方程中的常数已由实验确定。用本模型计算了管内超音速混合流动,其理论计算曲线与实验数据相当符合,证明该模型较不可压紊流模型更为适用。

A COMPRESSIBLE TWO-PARAMETER MODEL OF TURBULENCE AND ITS APPLICATION

A modified turbulence model is proposed to predict the mixing process of supersonic flows. It differs from the ordinary K-KL two-parameter model in taking account of the compressibility, which should not be neglected in supersonic flow.By general approach similar to that for incompressible flow, the turbulent kinetic energy equation is derived for compressible flow（Eqs 10 and 11）. .In the way-similar to the semiempirical method for incompressible flow, the K-KL equation is written as Eqs 18 and 19. The constants in Eqs 18 and 19 are determined by fitting the calculation curve to the experimental data. The free-jet, fully-developed duct flow and. duct flow with supersonic mixing are predicted with this method and compared with the relevant experimental data favorably. It is also shown that it is impossible to obtain the satisfactory predictions for supersonic flow if compressibility effect is not considered.