多层鼓泡弹性支承箔片动压气体轴承的实验研究

Experimental Study on the Performance of Multi-decked Elastic Support Protuberant Foil Gas Bearing

在单层鼓泡箔片动压气体轴承的基础上,提出了多层鼓泡箔片轴承的新型结构.该种新型结构可以通过合理选择上下层鼓泡箔片上鼓泡的结构参数和相对位置,产生不同的刚度和阻尼效果.该种轴承结构弹性支承元件的轴向和周向刚度可调,且具有良好的结构阻尼特性;同时多层鼓泡箔片之间的滑移能够产生附加库仑阻尼,因此提高了轴承的稳定性.实验中透平膨胀机采用25 mm直径的转子时最高转速达到了99 044 r/min.在整个升速和降速过程中低频涡动均较小,验证了此种新型箔片轴承具有优异的抑制不稳定涡动的效果,有望应用在高速透平机械中.

Based on the single deck protuberant foil gas beating, a new type of foil bearing composed of multi-decked structure was proposed. The relative position of the protuberant of different decks arranged to produce variable stiffness and damping effects. This new configuration possesses controllable stiffness in axial and circumferential direction, as well as the additional coulomb damping between the stacked layers, could improve the bearing stability. In the experiment, the maximal running speed of the 25mm diameter rotor in the turbo-expander reached 99 044 r/min. In the whole speed up and down processes, the amplitude of subsynchronous whirl is small which verifies the suppression effect of the new configuration, therefore, this new foil bearing can be applied in high speed turbomachinery.