河海大学学报(自然科学版)
河海大學學報(自然科學版)
하해대학학보(자연과학판)
JOURNAL OF HOHAI UNIVERSITY (NATURAL SCIENCES)
2010年
2期
236-240
,共5页
张卓%宋志尧%孔俊%张凤
張卓%宋誌堯%孔俊%張鳳
장탁%송지요%공준%장봉
k-kl模型%稳定函数%壁函数%稳态里查德森数
k-kl模型%穩定函數%壁函數%穩態裏查德森數
k-kl모형%은정함수%벽함수%은태리사덕삼수
k-kl model%stability function%wall function%steady state Richardson number
为了考察k-kl模型在风生混合流的应用效果,将影响其紊动扩散模拟结果的因素归结为3类:一是稳定函数的不同;二是壁函数的不同;三是稳态里查德森数Ri_(st)的不同.从这3个方面着手对k-kl模型进行分析,比较各种不同方法对混合层及紊动扩散的影响,并采用国外试验结果来检验数值模拟结果.结果表明:稳定函数的选取对计算结果会有影响,相比之下,较新的模型如CA,CB,CH能得出比传统的MY,KC更精确的结果;抛物改进型的壁函数的结果稍好于抛物线型和对称型壁函数;稳态里查德森数对混合层的发展有重要影响,当它的值增大时,同时刻混合层深度也会增加.
為瞭攷察k-kl模型在風生混閤流的應用效果,將影響其紊動擴散模擬結果的因素歸結為3類:一是穩定函數的不同;二是壁函數的不同;三是穩態裏查德森數Ri_(st)的不同.從這3箇方麵著手對k-kl模型進行分析,比較各種不同方法對混閤層及紊動擴散的影響,併採用國外試驗結果來檢驗數值模擬結果.結果錶明:穩定函數的選取對計算結果會有影響,相比之下,較新的模型如CA,CB,CH能得齣比傳統的MY,KC更精確的結果;拋物改進型的壁函數的結果稍好于拋物線型和對稱型壁函數;穩態裏查德森數對混閤層的髮展有重要影響,噹它的值增大時,同時刻混閤層深度也會增加.
위료고찰k-kl모형재풍생혼합류적응용효과,장영향기문동확산모의결과적인소귀결위3류:일시은정함수적불동;이시벽함수적불동;삼시은태리사덕삼수Ri_(st)적불동.종저3개방면착수대k-kl모형진행분석,비교각충불동방법대혼합층급문동확산적영향,병채용국외시험결과래검험수치모의결과.결과표명:은정함수적선취대계산결과회유영향,상비지하,교신적모형여CA,CB,CH능득출비전통적MY,KC경정학적결과;포물개진형적벽함수적결과초호우포물선형화대칭형벽함수;은태리사덕삼수대혼합층적발전유중요영향,당타적치증대시,동시각혼합층심도야회증가.
In order to evaluate the application of k-kl turbulence model in wind-induced mixing flows, the factors resulting in different simulated results of turbulent diffusion were categorized into 3 classes: different stability functions, different wall functions and different steady-state Richardson numbers Ri_(st). The k-kl turbulence model was analyzed from the 3 aspects. The influences of different methods on mixing flows and turbulent diffusion were compared. The numerical results were verified by use of the overseas test results. It is found that various stability functions have apparent influences on the calculated results, and the newer models such as CA, CB and CH will give more precise results than the conventional ones such as MY and KC. The improved parabolic wall function will lead to more reasonable results than the parabolic and symmetric wall functions. The steady-state Richardson numbers have great influences on the development of the mixing flows, and when they increase, the depth of the mixing flows will also increases.