螺旋槽端面气膜密封结构高温特性研究

Study on High Temperature Characteristics of Spiral Groove End Surface Gas Film Seal Structure

为了研究螺旋槽端面气膜密封结构在高温下的密封性能,建立了高温密封分析数学模型,研究了螺旋槽气膜密封的气膜温度、压力以及端面变形分布规律,在此基础上探讨了螺旋槽气膜密封的热变形机理,并进一步分析了不同密封压力、转速、环境温度下热效应对开启力和泄漏率的影响。结果表明:在高压、高速条件下,热效应使端面形成发散间隙,导致开启力减小,泄漏率增加;在低压、高速条件下,热效应使端面形成收敛间隙,导致开启力及泄漏率增大。对于螺旋槽端面气膜密封结构,环境温度的升高对端面变形的影响不明显,且环境温度从300 K升至550 K时,考虑端面热效应的开启力减小4%,泄漏率减少36%。

In order to study the seal characteristics of spiral groove end face gas film seal structure at high temperature,a mathematical model of high temperature seal analysis was established. The distribution of film temperature,pressure and end surface deformation of spiral groove gas film seal were studied. On this basis,the thermal deformation mechanism of spiral groove gas film seal was discussed. The influence of thermal effect on opening force and leakage rate was further analyzed under the conditions of different seal pressure,rotating speed and ambient temperature. The results show that under the conditions of high pressure and high speed,the thermal effect causes the end face to form divergence gap,which leads to the decrease of opening force and the increase of leakage rate. Under the conditions of low pressure and high speed,the thermal effect causes the end face to form convergence gap,which leads to the increase of opening force and leakage rate. For spiral groove end gas film seal,the effect of ambient temperature on the end face deformation is not obvious. When the ambient temperature increases from 300 K to 550 K,the opening force considering the thermal effect of the end face is reduced by 4% and the leakage rate is reduced by 36%.