摘要
翼型在不可压和低雷诺数条件下工作时的性能越来越引起了人们的研究兴趣。本文采用Rogers发展的双时间步Roe格式,求解拟压缩性修正不可压N-S方程。数值模拟了低雷诺数条件下(Re=6.0×104,1.0×105,2.0×106),E387翼型在不同攻角条件下(α=0°、4°、7°)翼上表面后缘部分的层流分离现象,对应于长分离泡。时均化的结果同McGhee[12]的试验结果进行比较,验证了计算结果的正确性。研究了低雷诺数层流分离的非定常和时均化特性,并对漩涡脱落中主涡、二次涡以及出现的漩涡对并的周期性过程和对气动力脉动造成的影响进行了较为细致的研究。非定常计算结果表明,低雷诺数条件下的层流分离现象,是周期性的旋涡脱落过程。所谓长层流分离泡是其时均化积分的结果。
The performances of the airfoil at low Reynolds number and incompressible flow conditions are studied in this paper. Two step Roe scheme developed by Rogers was used to solve the artificial compressible INS equations, in order to simulate the lumlnar separation of the F_,387 airfoil near the tAiling-edge at low Reynolds number （ Re = 6.0 × 10^4 , 1.0 × 10^5,2.0 × 10^6） and different angle-of-attack （α = 0°,4°, 7°）, corresponding to the long laminar separation bubble. The conection of the simulation was proved by comparing the present time-averaged results with the experimental results of McGhee . The unsteady and time-averaged characters of the laminar separation at low Reynolds number were studied. As well as the periodical periodcoed of the variation of the primary vortex, the secondary vortex, incorporation of vortex and the variation of the lift coefficient were analyzed more carefully. The restults of the unsteady simulation illustrate that the phenomenon of the low Reynolds number laminar separation is the periodically shedding of the vortex. And the long laminar separation bubble is the time-averaged result of that phenomenon.
出处
《空气动力学学报》
EI
CSCD
北大核心
2006年第4期416-424,共9页
Acta Aerodynamica Sinica
基金
国家自然科学基金资助项目(10232010
10032060)
关键词
低雷诺数
不可压
层流分离泡
非定常
low Reynolds nnmher
incompressible
laminar separation bubble
unsteady
