基于分形理论的多孔质气体止推轴承倾斜研究  

Research on Porous Thrust Air Bearing's Tilt Based on Fractal Theory

作　　者：张卫艳 林彬[1] 张晓峰[1] 金子才[1] ZHANG Weiyan;LIN Bin;ZHANG Xiaofeng;JIN Zicai(The State Education Ministry Key Laboratory of Advanced Ceramics and Machining Technology, Tianjin University, Tianjin 300354, Chin)

机构地区：[1]天津大学先进陶瓷与加工技术教育部重点实验室,天津300354

出　　处：《润滑与密封》2018年第4期34-37,共4页Lubrication Engineering

基　　金：国家自然科学基金青年项目(51205285)

摘　　要：多孔质节流器表面孔隙分布的不均匀性会导致多孔质气体轴承的倾斜。为寻找一种合适的方法来评价渗透率分布对多孔质轴承倾斜的影响,通过图像采集得到多孔质节流器表面孔隙的局部分形维数,然后利用局部分形维数的分布情况来评价渗透率的不均匀性,并提出分形维数分布向量来评估多孔质轴承的倾斜。通过实验测量多孔质轴承工作状态下的倾斜角度和方向。实验结果表明,该方法可以在不破坏多孔质节流器的情况下很好地预测多孔质轴承的倾斜:局部分形维数分布越集中则表明多孔质节流器的渗透率越均匀;根据分形维数分布向量的模可判断出轴承倾斜的角度大小,轴承倾斜的方向和分形维数分布向量的方向和达到了很好的吻合。The tilt of porous air bearing is caused by the non-uniformity of surface pores on the porous restrictor.In order to find a suitable method to evaluate the influence of permeability distribution on the tilt of porous bearings,the local fractal dimension of surface pores on the porous restrictor was obtained by the image acquisition,the distribution of local fractal dimension was employed to evaluate the non-uniformity of permeability,and the distribution vector was proposed to evaluate the tilt of porous bearing.The tilt angle and direction of porous bearing were measured in the working status.The experimental results indicate that the tilt of porous bearing can be forecasted by this non-destructive method,the more concentrated the distribution of local fractal dimension is,the more uniform the permeability is; the tilt angle can be estimated by the norm of distribution vector and the tilt direction is consistent with the direction of distribution vector.

关 键 词：多孔质气体轴承 渗透率 分形维数 分布向量 倾斜 

分 类 号：TH133[机械工程—机械制造及自动化]