摘要
本文提出了一种新的紊流模型,即k-ε-S(turbulent kinetic energy-dissipation-Stochastic theory)模型。该模型采用窦国仁的紊流随机模型,其涡粘性系数为二阶张量,从而克服了k-ε-E(turbulent kinetic energy-dissi-pation-Eddy viscosity)模型中Boussinesq各向同性涡粘性系数假设的缺陷。可以证明,k-ε-E模型可看成是k-ε-S模型的特殊情况。提出了适用于k-ε-S模型及应用范围较广泛的壁函数关系。通过对宽明渠均匀流和方腔流的计算表明,提出的k-ε-S模型是成功的,且优于k-ε-E模型。
A new turbulence model, the k-ε-S(turbulent kinetic energy-dissipation-Stochastic theory) model is presented. Instead of theBoussinesq's eddy viscosity concept in the k-ε-E(turbulent kinetic energy-dissipationEddy viscosity)model, which means the introduction of the isotropic eddy viscosity, the turbulent stochastic theory developed by Dou Guoren, in which the eddy viscosity is a second-order tensor, is used in the k-ε-S model. Itcanbe shown that the k-ε-E model is the special case of the k-ε-S model. The wall functions which are appropriate to the k-ε-S model and general cases are deduced. Numerical results of the twodimensional channel uniform flow and square cavity flow show that the k-ε-S model is successful and superior to the k-ε-E model.