摘要
氢氧火箭发动机氧涡轮泵中氦气隔离密封的作用是防止驱动涡轮的富氢燃气和液氧介质相混合,目前国外氦密封主要应用的是带瑞利(Rayleigh)动压槽的圆周分段式密封,可以有效减少氦气消耗量。这种密封形式设计的关键在于计算动压槽所产生的动压浮起力。利用Fluent流体分析软件,计算了动压浮起力,并与一维计算方法和国外文献中计算结果相比较,验证了三维仿真计算方法的准确性;分析了气膜厚度、动压槽深度、槽数以及加工误差导致的轴偏斜和槽偏斜等因素对浮起力的影响,密封浮起力随气膜厚度的增大而减小,动压槽深度约为0.01mm,浮起力达到最大值,轴偏斜和槽偏斜角度越大,浮起力越小。
The helium gas isolation seal in the oxygen turbopump of LOX/LH 2 rocket engine is used to prevent the mixture of the liquid oxygen and the hydrogen-enriched gas driving the turbine.At present, the main application of helium seal abroad is the circumferential segmented seal with Rayleigh step hydrodynamic lift pad, which can effectively reduce the helium leakage.The key to this seal design is to calculate the opening force generated by Rayleigh step hydrodynamic lift pad.In this paper, the opening force was calculated by Fluent fluid analysis software, and the accuracy of the three-dimensional simulation calculation method was verifiedby compared with the results of one-dimensional calculation method and the calculation results in foreign literatures.In addition, the effects of the gas film thickness, the number and the depth of Rayleigh steps, the distortion of shaft and Rayleigh step caused by machining errors on the opening force were analyzed.The opening force decreases with the gas film thickness increasing.The opening force reaches its maximum when the depth of Rayleigh steps is 0.01 mm.The larger the shaft distortion and the Rayleigh step, the smaller the opening force.
作者
李小芬
周芮
涂霆
LI Xiaofen;ZHOU Rui;TU Ting(Beijing Aerospace Propulsion Institute, Beijing 100076, China;Xi'an Aerospace Propulsion Institute, Xi'an 710100, China)
出处
《火箭推进》
CAS
2019年第5期45-51,共7页
Journal of Rocket Propulsion
关键词
圆周分段式密封
瑞利动压槽
动压浮起力
三维数值仿真
circumferential segmented seal
Rayleigh step hydrodynamic lift pad
opening force
three-dimensional numerical simulation
