摘要
应用流体动力润滑理论分别建立固定悬浮体以及自由悬浮体的超声气体挤压膜气膜压力模型,并对模型进行数值求解,获得超声频振荡气体挤压膜的压力分布及承载能力,在此基础上利用Christensen平均模型讨论了表面粗糙度对承载能力的影响。结果表明:气体挤压膜具有较大的承载能力,且承载能力大小主要取决于挤压运动的振幅和频率,其中,振幅对气体挤压膜承载力影响最为显著,而频率影响次之。低频范围内,频率对承载力的影响较大,而随着频率的升高其影响逐渐趋于平稳。构造适当的表面纹理可以在一定程度上提高气体挤压膜的承载力。研究结果可以为超声悬浮器件或涉及挤压膜问题的微纳器件设计提供参考。
The paper presented the models of fixed object and freedom levitating object on the ultrasonic squeeze gas film.The models were solved by numerical methods,and then the pressure distribution and load capacity of squeeze film were obtained.The influence of surface roughness on the properties of squeeze film was studied by the use of Christensen average model.The results show that squeeze film has larger load carrying capacity,and the load capacity depends on the exciting amplitude and frequency.The effects of exciting amplitude is more significant in the two factors,the effect of frequency on the load capacity decreases gradually with the increase of frequency and then turns to be smooth gradually.It is shown that appropriate surface texture can increase the levitation load capacity.The conclusion of this paper can be used in the design of ultrasonic levitation and micro/nano devices for reference.
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2013年第20期2785-2790,共6页
China Mechanical Engineering
基金
国家自然科学基金资助项目(50975138)
关键词
近场超声悬浮
气体挤压膜
承载力
表面粗糙度
平均模型
near field ultrasonic levitation(NFUL)
gas squeeze film
load capacity
surface roughness
average model