气浮球轴承中层板微缝散布式气膜流动及热皱损研究

At present, aerospace and precise engineering have urgent demand for high performance spherical air bearing. Based on the research on the platelet precise distributary and transpiration cooling theory, the satellite 3-axis attitude control air bearing table developed by the proposer, and the technology of the fluid heat transfer and distributing flow in the platelet's micro channels, a new concept about spherical air bearing composed by platelets with micro distributing channels is brought up, meanwhile, the gaseous film flow and the thermal wrinkling theroy is carried on. A spherical air bearing is fabricated by stacking several thin sheets, which are less than 1mm thickness, in predetermined sequence. The air in the platelet's micro channels accurately distributes, diffusedly flows, fully transfers heat to each other, and it is uniformly distributed in wall structure of the air bearing's stator. Then the air flows from platelet's micro channels into the gaps between the stator and the rotor in the air bearing, and a gaseous film is formed to suspend and carry the high-precision rotor. Moreover, analytic solutions with numerical simulation is adopted to study the new gaseous film's flow mechanism, the thermal wrinkling effeted by temperature rise in the platelet structure, sensitive platelet parameters in relevant with the Relative Entropy Theory. This research project pays great attention to the exploration of a new approach, which can stably operate in wide temperature range, to achieve high carrying capacity, high stiffness, nearly free friction, good damping characteristic, and to provide a new method and theoretical bases for high-precision air bearing tables for satellites and ultra rotational speedy spindles in our nation.

针对当前航空航天、精密工程等领域对高性能气浮球轴承的迫切需求，在申请人关于层板精细分流与发汗冷却、小卫星三轴气浮台的研究基础上，基于层板微小通道流体传热和散布流动技术，提出层板微缝散布式气浮球轴承的概念，并对其进行气膜流动及热皱损研究。多个小于1mm厚的层板，按照特定顺序排列构型，使气体在微小通道内精细分流、散布流动、充分换热，均匀散布在气浮球轴承定子壁面结构中，最后经层板微缝流出进入轴承间隙，形成承载转子高精度回转的气膜。由理论解析求解和数值模拟计算结合的方式，探索新型气膜流动的工作机理，确定温升对壁面层板结构的热皱损影响，分析相对熵理论下层板参数的敏感度。探求既具有高承载和高刚度性能，又具备摩擦力微小和阻尼特性优良的效果，同时能够在宽温度范围内稳定工作的气浮球轴承新技术实现手段和理论分析方法，为我国卫星高精度三轴气浮台、高转速气浮式主轴等研究提供新的思路和理论参考。

本课题针对当前航空航天、精密工程等领域对高性能气浮球轴承的迫切需求，在申请人关于层板精细分流与发汗冷却、小卫星三轴气浮台的研究基础上，基于层板微小通道流体传热和散布流动技术，提出了层板微缝散布式气浮球轴承的概念，并对其进行了气膜流动及热皱损研究。.对于定子壁内小尺度散布流道的流动和换热研究，采用宏观/微观理论对比分析方法，从宏观到微观，基于结构层板和流道的特征尺寸，选用不同的理论来分析了气体流动与换热。对于轴承定子壁外气膜流动和换热特性的研究，采用双球坐标系下层板表面简单扩散流动的解析方法，与在复杂工况下三维数值模拟方法，进行了对比研究。.采用理论解析求解和数值模拟计算结合的方式，探索了新型气膜流动的工作机理，研究了温升对壁面层板结构的热皱损影响，分析了相对熵理论下层板参数的敏感度。对典型层板发汗冷却的结构层板进行热力耦合特性研究及试验验证。针对结构层板的热皱损问题，对层板温度、板厚、缝隙宽度与挠曲临界压应力的关系做出了计算分析。.探求既具有高承载和高刚度性能，又具备摩擦力微小和阻尼特性优良的效果，同时能够在宽温度范围内稳定工作的气浮球轴承新技术实现手段和理论分析方法，为我国卫星高精度三轴气浮台、高转速气浮式主轴等研究提供新的思路和理论参考。.