射流管伺服阀前置级压力特性

为分析射流管伺服阀射流管喷嘴高压射流区的特性,建立了射流管伺服阀前置级数学模型,得到了射流管偏移值、射流管喷嘴半径和接收孔半径对接收器压力分布、喷嘴出口流速及接收器的左右孔恢复压力的影响规律.流场分析发现射流管喷嘴的高速射流出口处容易产生旋涡,且存在环状负压效应.结果表明:高压射流状态下,射流管喷嘴半径增大,恢复压力增加;接收孔半径增大,恢复压力降低.接收孔半径与射流管喷嘴半径之比的最佳取值区间为1.3,1.5].当射流管偏移值增大时,在偏移值增大一侧,射流管与接收孔之间的有效流体接收面积增大,射流管与接收孔之间的流体旋涡扩大,内部流场环状负压效应增加,接收孔恢复压力降低.

Pressure characterization of the pre-stage of jet pipe servo valve

In order to analyze the characteristic of high jet pressure of jet pipe nozzle in the jet pipe servo valve, a pre-stage jet pipe servo valve mathematical model was established to get the impact of the jet pipe deflection displacement, the radius of jet pipe nozzle and the radius of receiving hole on its internal fluid pressure, nozzle exiting velocity and recovery pressure in the left and the right holes of receiver. Flow field analysis found that vortex was prone to occur at high velocity jet exit, and there existed annular negative pressure effect. The results showed that:under high jet pressure, when the radius of jet pipe nozzle increased, the recovery pressure increased, and when the radius of receiving hole increased, the recovery pressure decreased. The best internal value of the ratio of the radius of receiving hole to the radius of the jet pipe nozzle was1.3, 1.5]. When jet pipe deflection displacement increased, on the side of displacement increase, the effective recieving area between the jet pipe and the receiving hole increased, but the vortex between the jet pipe and the receiving hole expanded and the annular negative pressure effect of the internal flow field increased, and the recovery pressure of the receiving hole decreased.