工程科学与技术2017，Vol.49Issue(2)：248-253,6.DOI:10.15961/j.jsuese.201601188
倾斜椭圆微孔端面机械密封的回吸现象及对泄漏量影响
Outlet Suction and Leakage of Mechanical Seal with Inclined Elliptical Dimples
吉华 1陈枭 1王彦镐 1张科 1陈志1
作者信息
- 1. 四川大学化学工程学院,四川成都610065
- 折叠
摘要
Abstract
It has been showed directly or indirectly that the lubricant is possible to be sucked back into the mechanical seal with dimples or grooves in the existing studies.This phenomenon,termed "outlet suctio" in this paper,may decrease the leakage.Further studies are still required for this phenomenon and its mechanism.A three-dimensional fluid numerical simulation,based on the multiphase flow cavitation model in Fluent,was developed for the mechanical seal with inclined elliptical dimples.The causes of outlet suction and the influence of the outlet suction on leakage were studied by changing the differential pressure between the inner and outer diameter and the rotation rate.Firstly,in order to ensure the accuracy of calculation model,the fluid factor was calculated for the flow pattern check,the grid independence was tested for the grid size,and the simulation result was compared with the reference.Secondly,in the numerical simulation experiments,the phenomenon of outlet suction was observed directly in the streamline plots on the r-θ section of calculation unit beside the outlet section and the velocity distribution contours in radial direction on the outlet section.Thirdly,the pressure and radial velocity distribution on r-θ section was discussed.The results showed that the outlet suction occurs because the pressure close to the seal outlet falls below the external atmospheric pressure.This pressure decrease is caused by the hydrodynamic effect near the divergence gaps of dimples.The increase of hydrodynamic effect enhances the outlet suction.When the decreased pressure reaches the cavitation pressure,the cavitation occurs.The cavitation effect hinders the increase of outlet suction.Finally,the effect of Ap and n on outlet suction,and the effect of outlet suction on the leakage decrease were studied based on the analysis of the out flow rates and outlet suction flow rates.The leakage decreases because of the outlet suction,even to zero.The outlet suction caused by inclined elliptical dimples can be employed to decrease the leakage of mechanic seals.关键词
机械密封/倾斜椭圆形微孔/回吸现象/泄漏量Key words
mechanical seal/inclined elliptical dimple/outlet suction/leakage分类
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吉华,陈枭,王彦镐,张科,陈志..倾斜椭圆微孔端面机械密封的回吸现象及对泄漏量影响[J].工程科学与技术,2017,49(2):248-253,6.
