并列双发三维非对称多S弯喷管参数化设计方法

形成了一套基于CFD计算评价的并列双发三维非对称多S弯喷管参数化设计方法,并初步证明了该方法的正确性和可行性.多S弯中心线在Z向偏心度为0时:第一S弯Y向偏心度、长度都最小,第二S弯Y向偏心度、长度都最大,第三S弯Y向偏心度、长度分别介于前两个S弯对应参数之间,各S弯都采用进口缓慢转弯,出口快速转弯的规律,以利于抑制背风侧分离和涡.剖面在各S弯上都采用进口快速收缩缓慢转弯,出口缓慢收缩快速转弯的规律,且宽高比与侧边倾角在进出口变化速率相同,且侧边倾角只分布在第一S弯上,以利于稳定流场和增加隐身性能.合流器采用楔底宽高比约束,其值应不超过0.26. 

Parameter design method of double juxtaposition 3-D asymmetric several-S-shaped nozzles

A suit of parameter design methods of double juxtaposition 3-D asymmetrical several-S-shaped nozzles based on CFD numerical simulation technology was estabished, and the exactitude and feasibility of the parameter design methods were approved primarily. The several-S-shaped centerline on the condition of Z direction eccentricity angle of 0: Y direction eccentricity angle and location parameter L of the first S curve are smallest,and the two parameters of the second S curve are biggest. The two parameters of the third S curve are between the biggest and the smallest of the pre two S curves. Every S curve uses the law which turns slowly at inlet, but quickly at outlet to favor controlling the airflow separation and turbulence of the leeward. The section uses the law which shrinkages quickly and turns slowly at inlet, but shrinkages slowly and turns quickly at outlet,and the aspect ratio and the side obliquity varies at the same rate at inlet and outlet. The side obliquity only distributes on the first S curve to favor stabilizing fluid flow and increasing stealth performance. Confluence implement uses wedge fundus/highness aspect ratio restriction, and it should not exceed 0.26.