CAJ | 학술논문

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.
장뢰낙응력방정불동봉폐방식귀결위은정함수적차이,병이차작위구분표준,총결료6충국내외채용과적은정함수병이통일적형식렬출,분석불동문류모형은정함수적분포화영향인소,병차통과실험자료진행료비교분석,발현(1)2000년후제출적3충은정함수득도적림계리사덕삼수대우2000년전적3충,경부합실제정황,저여기재압강응변상관항화부력상관항중증가료선전효응화중분포효응유관;(2)진관저3충모형고필적인소경가전면,단재모사특정장합하,여변계층,여실험적문합정도반불여전3충교조적은정함수,반영료봉폐모형본신존재적결함.최후,제출료이계문류봉폐모형환대해결적문제.
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: (1) 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.