Influence Factors Of Labyrinth Seal Effect Of Large Reciprocating Compressor

The labyrinth seal is a kind of non-contact sealing structure, which has the advantages of simple structure, stable operation, long service life, has been used between piston and cylinder in large reciprocating compressor. In the working process of reciprocating compressor, the labyrinth seal structure ensures gas without exhausting oil, ensures no dust and no wear debris inside the cylinder and also avoids pause phenomenon of reciprocating piston. Labyrinth seal relies on the gas energy dissipation to achieve sealing performance of gas in the flow process.In order to improve the sealing effect of labyrinth seal, studying the mechanism of labyrinth seal of internal gas is very important.In this dissertation, ANSYS Workbench is taken as working platform to perform three dimensional modeling of the flow field in straight teeth type axial labyrinth seal structure.Computational fluid dynamics FLUENT software is used to analyze the gas flow for different labyrinth sealing structures and further improve the theoretical research of labyrinth seal. The purpose is to make some contribution to the localization of reciprocating labyrinth seal compressor. The specific research contents are summarized as follows:(1) On the background of large-scale reciprocating labyrinth seal compressor, the sealing mechanism, types and the domestic and international research actuality of labyrinth seal are summarized. Basic theory of labyrinth seal is discussed and introduced.(2) The geometricl model and mathematical model of labyrinth seal are established, and the numerical calculation method of internal flow field in labyrinth seal is determined.FLUENT software is adopted to compare the sealing effect of bilateral labyrinth seal structure with unilateral seal structure and smooth seal structure. The analysis results show that the bilateral labyrinth seal structure has better sealing effect.(3) The factors which affect the sealing effect of straight teeth labyrinth are simulated.The factors include the gap width, sealing cavity depth, sealing cavity width, throttling tooth width of piston side and cavity dimensions of cylinder side. The gas flow field for different labyrinth seal structure is analyzed and the flow characteristics are obtained. The effect of each factor on the labyrinth sealing performance is summarized.(4) The angle of inclined labyrinth throttling teeth is taken as research variables toanalyze the leakage of labyrinth seal for different inclined throttling teeth. The leakage obtained with numerical simulation method is compared with the results from classical calculation method. The validity and accuracy of the mathematical model and numerical simulation of labyrinth seal with inclined teeth are verified.