挤压油膜阻尼器中的气穴

Cavitations in Squeeze Film Dampers

对挤压油膜阻尼器气穴试验进行了综合考察分析，对气穴产生、型式和特征进行了阐述。指出挤压油膜阻尼器与静载下普通轴承有不同的气穴特征，即高压区存在有空气小气泡气穴，低压区可能有蒸汽气穴的产生。通常采用的均匀不可压流假设，以及负压置零的气穴和压力边界条件是欠妥的。需提出油气两相流的理论分析模型，并寻求建立蒸汽气穴的边界条件，以准确预计挤压油膜阻尼器的力学性能；应进行挤压油膜阻尼器压力分布的实测，进一步为建立理论模型提供依据。

An investigation on the cavitation experiments of squeeze film dampers is made and cavitation patterns and features are discussed. It is pointed out that the cavitation in squeeze film dampers is different from that in journal bearings. Small air cavitation bubbles can persist in the high pressure region,and vapour cavitations rnay occure around the negative peak pressure region of the dampers Therefore,the incompressible fluid and π-film model assumed before is inappropriate. Oil-air two-phase compressible fluid model and vapour cavitation boundary conditions are required to be established to calculate damper performances accurately. The pressure distributions of squeeze film dampers should also be measured to provide further experimental bases for establishing theoretical medels