运载火箭复杂管路随机性压力跳变机理及抑制

针对3种典型的管路随机性压力跳变现象，通过仿真分析，提出管路中的直角多通结构使管内流动具有非线性的流动多解特性，在特定扰动条件下，会产生多通内的大涡结构及沿分支管的螺旋流动，引起额外的流阻，并导致管路局部压力发生跳变，从机理上复现了复杂管路内的随机性压力跳变现象；在此基础上，提出了增加导流结构/隔板结构抑制多通内大涡流动的改进方案，并针对真实管路结构，开展了管路压力跳变现象的地面复现及抑制改进试验，试验结果表明:3种直角多通结构均存在流动多解特性，增加导流结构可有效消除管路中的随机性压力跳变现象。 

Mechanism and suppression of random pressure jump in complex pipeline system of launch vehicles

In view of at three random typical pressure jump phenomena due to complex pipeline layout and high flow velocity, the nonlinear multi-solution flow characteristics in right-angle multi-way pipeline were proposed by numerical simulation. Under certain disturbance conditions, a large eddy in the multi-way cavity and spiral flow along the branch pipeline were formed, which caused additional flow resistance and local pressure jump in complex pipeline. On the basis, in order to eliminate the large eddy in the multi-way cavity, the suppression scheme by appending guide devices or baffles was proposed. With the actual pipeline layout, the ground recurrence test and suppression improvement test of random pressure jump phenomena were carried out. The experimental results indicated that the multi-solution characteristics of the three complex multi-way pipeline were validated, and the improved scheme can effectively eliminate the random pressure jump phenomena.