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针对受壁面限制的涡对融合问题,以多段翼型的二元风洞试验为例,用雷诺平均的NS方程进行了模拟。结合侧壁面的表面摩擦力线、不同x向横截面流线的拓扑结构分析及总压分布云图,刻画了多段翼型的涡流流场结构,进而分析了受侧壁面干扰的涡对融合过程。并与无侧壁面干扰的涡对融合过程进行了比较。结果发现,壁面对涡对融合过程的影响,包括了对旋涡发展速度的延迟、旋涡诱导速度的限制及壁面摩擦引起的能量损失等方面,明显延长了涡对融合所需的时间。但是侧壁面干扰的影响范围有限。根据以上结果,建议二元风洞试验中,试验段宽度应考虑侧壁面影响范围;对展弦比较大的半模,应对机身加上垫块或者采用镜像法来消除侧壁面对襟翼涡等的干扰;对于展弦比较小的模型,则应采用全模进行试验。
In the case of the vortex-pair fusion problem limited by the wall, a multi-section airfoil wind tunnel test is taken as an example to simulate the Reynolds-averaged Navier-Stokes equations. Combining the surface frictional force of the side wall, the topological structure of the streamlines with different x-direction cross-sections, and the total pressure distribution cloud, the vortex flow field structure of the multi-section airfoil is depicted, and the vortex-pair fusion process disturbed by the side wall surface is analyzed. The vortices with no side wall interference were compared. The results show that the influence of wall vortex on the fusion process includes the delay of vortex development, the restriction of vortex induced velocity and the energy loss caused by wall friction, which obviously prolongs the time required for vortex fusion. However, the influence of side wall interference is limited. Based on the above results, it is suggested that in the dual wind tunnel test, the width of the test section should consider the influence range of the side wall; for the semi-mold with larger aspect ratio, the body should be equipped with the spacer or the mirror method should be used to eliminate the sidewall facing flaps vortex Of the interference; for the modest aspect ratio model, you should use the full model test.