无油涡旋压缩机涡旋齿齿顶密封结构的研究

本文对无油涡旋压缩机涡旋齿齿顶密封结构进行优化，提出一种新型径向组合密封结构，利用几何和工程流体力学的方法，推导出基圆渐开线无油涡旋压缩机齿顶光滑间隙密封、齿顶迷宫密封、齿顶组合密封泄漏量的算法，建立了无油涡旋压缩机相邻压缩腔实验台，分别测量了3种密封结构在相同压差条件下的气体泄漏量，并研究了无油涡旋压缩机动涡旋盘转速对泄漏量的影响。对比实验与理论计算结果可得：理论计算结果与实验结果基本相近，光滑密封与迷宫密封泄漏量随压差的增大而增大，而组合密封泄漏量与压差成反比，但密封条磨损量增加。迷宫密封泄漏量实测值约为光滑密封实测值的80%，组合密封泄漏量实测值约为光滑密封实测值的63%，且3种密封结构的径向泄漏量随动涡旋盘转速的提高而降低，当动涡旋盘转速超过4 000 m/s时趋于平稳。

Study on the Sealing Structure of Scroll Tooth of an Oil-free Scroll Compressor

A novel type of radial combined sealing structure was proposed to improve the end-face sealing of wraps between fixed and orbiting scrolls. Geometry and engineering fluid mechanics were considered to develop an algorithm for determining leakage from the tooth top of the base circular involute oil-free scroll compressor with a smooth clearance tip seal, labyrinth tip seal, and combination tip seal. A simulation platform to test adjacent compression chambers for scroll compressors was established to measure the gas leakage of three sealing structures under the same pressure difference. The experimental and theoretical calculation results were compared, and the theoretical calculations were identical to the measured results. The amount of leakage from the smooth seal and labyrinth seal increased as pressure difference increased, while the leakage amount of the combined seal was inversely proportional to the pressure difference. However, the wear amount of the seal increased. The measured leakage of the labyrinth seal was 80% that of the smooth seal, and the measured leakage of the combined seal was 63% that of the smooth seal. Thus, we can confidently conclude that the combination sealing structure is more suitable for large compression ratio scroll compressor applications. Furthermore, the radial leakage of these three sealing structures decreases as the speed of the moving scroll increases. This tends to be stable when the rotational speed exceeds 4000 m/s.