波度对高温螺旋槽端面密封气膜承载能力的影响  

Influence of Waviness on the Bearing Capacity of Gas Film of High Temperature Spiral Groove Face Seal

作　　者：乔阳 王荣[1] 白少先[1] QIAO Yang;WANG Rong;BAI Shao-Xian(College of Mechanical Engineering,Zhejiang University of Technology,Hangzhou 310032,China)

机构地区：[1]浙江工业大学机械工程学院,杭州310032

出　　处：《工程热物理学报》2022年第4期898-906,共9页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助(No.51775504)。

摘　　要：基于表面粗糙和波度假设,考虑接触摩擦热,建立了高温螺旋槽气体端面密封润滑分析模型,采用有限差分方法对气膜压力、温度分布和表面接触力进行了数值迭代求解,重点分析表面波度对气膜承载力和泄漏率的影响规律。结果表明:表面波度对螺旋槽密封气膜压力分布、承载能力和泄漏率影响明显,全膜润滑状态下表面波度使得气膜承载能力下降、泄漏率增加,在3~5μm膜厚设计区间内,表面波度波幅增加到0.8~1.5μm可使得气膜开启力下降5%,泄漏率增加50%以上;混合润滑或小膜厚状态下,接触摩擦热可导致明显的气膜温升,并且表面波度可使气膜承载能力和泄漏率增加;螺旋槽密封气膜承载能力和泄漏率随环境温度的增加均呈现单调增加的变化趋势,温升200 K条件下开启力、泄漏率的增幅均可达到10%。Based on assumption of surface roughness and waviness, a lubrication analysis model of high temperature spiral groove face gas seal lubrication was established considering the surface contact friction heat. The gas film pressure, temperature distribution and surface contact force were solved by means of the finite difference method, and the influence of surface waviness on the bearing capacity and leakage rate of the gas film was emphatically analyzed. The results show that the surface waviness has a significant effect on the pressure distribution, bearing capacity of gas film and the leakage rate of the seal. Under the condition of full film lubrication, the existence of the surface waviness contributes to the decline of the bearing capacity and the increase of the leakage rate.When the surface waviness amplitude increases to 0.8~1.5 μm, the opening force decreases by 5%and the leakage rate increases by more than 50% within the design range of 3~5 μm film thickness.Under the condition of mixed lubrication or small film thickness, the heat of contact friction leads to an obvious temperature rise of gas film, and the bearing capacity and leakage rate are increased owing to the surface waviness. Besides, the bearing capacity of the gas film and leakage rate of the seal show a monotonically increasing trend with the rise of ambient temperature, and the increase of opening force and leakage rate could grow by 10% when the ambient temperature increases by 200 K.

关 键 词：螺旋槽端面气膜密封 表面波度 粗糙度 摩擦热 

分 类 号：TH117.2[机械工程—机械设计及理论]