CAJ | 학술논문

采用数值模拟技术研究了2m×2m超声速风洞设计引导试验大开角扩散段配置一个中心倒锥和两层球冠状孔板的内流场,中心倒锥和两层球状孔板的不同组合共有五套.孔板有几百至上千个开孔,是模拟的难点,发展了一种孔板流动CFD边界条件模型.另一个难点在于风洞管道内流人口和出口边界条件的准确处理.计算表明,分流锥可将流动有效抑制在大开角洞壁附近,防止洞壁附近的扩张分离,但在分流锥底部将产生大尺度的分离涡环结构,经过孔板的整流后,总压有较大损失,但流线趋于平直,可达到预期效果.
채용수치모의기술연구료2m×2m초성속풍동설계인도시험대개각확산단배치일개중심도추화량층구관상공판적내류장,중심도추화량층구상공판적불동조합공유오투.공판유궤백지상천개개공,시모의적난점,발전료일충공판류동CFD변계조건모형.령일개난점재우풍동관도내류인구화출구변계조건적준학처리.계산표명,분류추가장류동유효억제재대개각동벽부근,방지동벽부근적확장분리,단재분류추저부장산생대척도적분리와배결구,경과공판적정류후,총압유교대손실,단류선추우평직,가체도예기효과.
The inner flowfields of the big open diffuser composed of a pointed cone for separate flow and two screens in five combinations are numerically studied, which were conducted for the 2m×2m supersonic wind tunnel design test analysis. There are hundreds of or even thousands of small holes on the screen, which makes the flow across the screen very difficult to be computed directly by CFD method. To overcome this problem, a boundary model for the flow across screen was built up. Another key technique in the CFD process is the accurate treatment of the inflow and outflow boundary. The numerical results show that the pointed cone can control the separation effectively near the wind tunnel wall, but strong vortex is generated behind the cone base, then the flow get across the screen with big total pressure loss, but the streamlines be-come straight. The effect was as expected.