近海区域二阶紊流封闭模型的比较研究

Comparison of two-order closure model in coastal areas

将雷诺应力方程不同封闭方式归结为稳定函数的差异,并以此作为区分标准,总结了6种国内外采用过的稳定函数并以统一的形式列出,分析不同紊流模型稳定函数的分布和影响因素,并且通过实验资料进行了比较分析,发现(1)2000年后提出的3种稳定函数得到的临界理查德森数大于2000年前的3种,更符合实际情况,这与其在压强应变相关项和浮力相关项中增加了旋转效应和重分布效应有关;(2)尽管这3种模型考虑的因素更加全面,但在某些特定场合下,如边界层,与实验的吻合程度反不如前3种较早的稳定函数,反映了封闭模型本身存在的缺陷。最后,提出了二阶紊流封闭模型还待解决的问题。

With advance of knowledge on turbulence and computer capability in recent years, two-order closure model has made new process. Different two-order closure models lead to different stability functions. Three earlier models （before 2000） and three later ones （after 2000） have been concluded in a unified form and then have been compared in the paper. After that some experimental data are compared with the model results. It is found that： （t） the later models （after 2000） obtain more realistic Richardson Number than the earlier models （before 2000） ; （2） in some particular tests, such as boundary layer, performance of earlier models is even superior to the later＇s, which reflects the faults of the later ones. Finally, problems to be solved are put forward.