恒星物理研究组知识库

为了将Li提出的k-ω模型应用到一般的恒星环境中,有必要研究其中模型参数的物理意义,以便限定它们的取值范围.研究表明,模型参数c'_μ的变化对湍流的Peclet数、湍动能、特征时标和特征长度都有影响,除此之外,随着它的增加,底部对流超射区中湍动能的衰减速率明显加快;模型参数c'_μ与等效混合长参数α都与对流传热效率成正比,它们的对数存在线性关系;模型参数c'_μ和底部对流超射区中湍动能的衰减指数θ之间取对数后也存在线性关系.对于太阳,可得到一组合适的模型参数值:c'_μ=0.004,α=1.7.

To apply the k - w model proposed by Li into common stellar environments, it's necessary to investigate the physical meanings of model parameters to confine their values. The research states that the variations of the model parameter c'_μ can impact the Peclet numbers, kinetic energies, typical time scales, and typical lengths of the turbulent flows. Besides, as model parameter c'_μ increases, the damping rate of the turbulent kinetic energy in the overshooting zone below the base of convection zone can be accelerated. Both the model parameter c'_μ and the equivalent mixing length parameter a are proportional to the efficiency of convective heat transfer in the convection zone, further investigation shows that their logarithms can satisfy a linear relation. There is also a linear relation between the logarithms of the model parameter c'_μ and the damping index θ of the turbulent kinetic energy in the convective overshooting zone. For the solar case, the following model parameters are appropriate: c'_μ = 0.004,α = 1.7.