为了研究螺杆膨胀机吸气端面泄漏特性，建立了端面压力非均匀分布模型与轴封泄漏模型，探究结构参数对轴封泄漏的影响。以应用最为广泛的迷宫密封为例，分析了齿顶间隙、空腔深度、空腔宽度和吸气端面间隙4个主要结构参数对轴封性能的影响。结果表明：轴封泄漏量随着端面间隙和齿顶间隙的增大而增大，随空腔宽度的增大而减小，且存在最佳深宽比，约为0.16；螺杆机械端面间隙对轴封泄漏量的影响最大，齿顶间隙、空腔宽度和空腔深度次之。

To study the leakage characteristics of the suction end face of the screw expander, the influence of structural parameters on the shaft seal leakage was investigated through the nonuniform end face pressure distribution model and the shaft seal leakage model. Taking the widely used labyrinth seal as an example, the influence of the four main structural parameters, namely tip clearance, cavity depth, cavity width and suction end face clearance, on the leakage of the shaft seal was analyzed. Results show that the shaft seal leakage increases with the increment of end face clearance and tip clearance and decreases with the increment of cavity width. And there exists an optimal depthtowidth ratio of about 0.16; the mechanical end face clearance of screw expander has the greatest influence on the shaft seal leakage, followed by the tip clearance, cavity width and cavity depth.

TK221

国家自然科学基金(52206016，51206022)；上海市青年科技英才扬帆计划(20YF1431700)