轴承腔壁面两相流动与换热是轴承腔精细化设计的基础,与腔壁结构密切相关。针对具有典型锥形结构特征的轴承腔内的油气两相流动和换热问题,基于相体积分数(Volume of Fluid,VOF)两相流动模型,通过与圆柱形轴承腔进行对比,参数化分析获...轴承腔壁面两相流动与换热是轴承腔精细化设计的基础,与腔壁结构密切相关。针对具有典型锥形结构特征的轴承腔内的油气两相流动和换热问题,基于相体积分数(Volume of Fluid,VOF)两相流动模型,通过与圆柱形轴承腔进行对比,参数化分析获得了锥形结构对流动及换热的影响,使用无量纲分析的方法,建立了适用于该锥形轴承腔常见工况范围内的对流换热准则式。研究表明:锥形轴承腔壁的换热量略小于柱形腔,锥形腔壁换热量随着发动机主轴转速的升高而增加,随着供油量的增加线性增加,随着封严气流量的增加先减小后增大。展开更多
A fiber-optic confocal microscope has been analyzed by Fourier optics.It is found that the detected light intensity has three parts,each of which is depennted on the coupled lens,the detective lens,and the part compri...A fiber-optic confocal microscope has been analyzed by Fourier optics.It is found that the detected light intensity has three parts,each of which is depennted on the coupled lens,the detective lens,and the part comprised of the fiber and the microprobe.The simulated results show that the less the value of the parameter A is,which is dependent on the fiber and microprobe,the higher the axial resolution of the system is. For the case,as A→∞, the axial resolution is zero,which is corresponding to the conventional microscope.as A≤1,the axial resolution changes slightly,and is close to the optimal value,which is corresponding to the perfect confocal microscope.when the reflective loss takes place at the end of fiber,the contrast of axial intensity will decrease.All that will help the design of endoscope with confocal microscope at cellular level.展开更多
文摘轴承腔壁面两相流动与换热是轴承腔精细化设计的基础,与腔壁结构密切相关。针对具有典型锥形结构特征的轴承腔内的油气两相流动和换热问题,基于相体积分数(Volume of Fluid,VOF)两相流动模型,通过与圆柱形轴承腔进行对比,参数化分析获得了锥形结构对流动及换热的影响,使用无量纲分析的方法,建立了适用于该锥形轴承腔常见工况范围内的对流换热准则式。研究表明:锥形轴承腔壁的换热量略小于柱形腔,锥形腔壁换热量随着发动机主轴转速的升高而增加,随着供油量的增加线性增加,随着封严气流量的增加先减小后增大。
文摘A fiber-optic confocal microscope has been analyzed by Fourier optics.It is found that the detected light intensity has three parts,each of which is depennted on the coupled lens,the detective lens,and the part comprised of the fiber and the microprobe.The simulated results show that the less the value of the parameter A is,which is dependent on the fiber and microprobe,the higher the axial resolution of the system is. For the case,as A→∞, the axial resolution is zero,which is corresponding to the conventional microscope.as A≤1,the axial resolution changes slightly,and is close to the optimal value,which is corresponding to the perfect confocal microscope.when the reflective loss takes place at the end of fiber,the contrast of axial intensity will decrease.All that will help the design of endoscope with confocal microscope at cellular level.