摘要
为了研究多孔质石墨静压气体推力轴承的静态特性,建立了相对应的理论计算模型.基于该模型分析了多孔质石墨密度、表面限制层、供气压力以及气体质量流量等因素对多孔质石墨静压气体推力轴承静态特性的影响.理论计算结果表明,轴承承载力与石墨密度成负相关、与供气压力成正相关,并在有表面限制层时较大;气体质量流量与石墨密度成负相关、与供气压力成正相关,并在有表面限制层时较大;轴承的刚度与石墨密度、供气压力成正相关,并在有表面限制层时较大.进一步设计实验台,绘制出多孔质石墨静压气体推力轴承的气膜厚度与承载力的静态特性曲线图.对比发现,实验结果与理论结果吻合较好,从而验证了数值计算方法的可靠性.
A theoretical calculation model was established to study the static characteristics of porous graphite aerostatic thrust bearings.Based on the proposed model,the effect of the related factors,such as porous density,surface-restricted layer,external gas pressure and mass flow rate on the static characteristics of porous aerostatic thrust bearings was analyzed.Theoretical calculation results show that the load-carrying capacity of the bearing is negatively correlated with the graphite density and positively correlated with the gas supply pressure,but it is smaller than that of the surface-restricted layer.Gas mass flow rate is negatively correlated with the graphite density and positively correlated with the gas supply pressure,but it is also smaller than that of the surface-restricted layer.Bearing stiffness is positively correlated with the gas supply pressure and graphite density,but it is smaller than that of the surface-restricted layer.According to the results,corresponding function diagrams were plotted.The test rig was then designed to plot the static characteristic curve of porous aerostatic thrust bearings,including the load-carrying capacity and gas film thickness.The numerical method was eventually verified by the experimental results.
引文
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