考虑微含气工况下温度效应的高速离心泵转子系统流致耦合振动特性

高速离心泵是液体输送系统的核心装置，广泛应用于航天航空、石油化工的重要工位。其转子系统在高转速、流体激励力、齿轮力与力偶等因素的共同作用，不再以横向振动为主，而是表现出明显的耦合振动特征。其中，流体激励力对耦合振动特性有重要影响。此外，在输送易汽化低密度液态介质时，因工况变化介质极易析出微量气体，使高速泵处于微含气工况并影响泵的流动及振动性能。现有离心泵研究多未考虑微含气对泵内流动特性、流体激励力特性，特别是间隙激励力特性的影响，也未开展这一激励下的转子系统耦合振动特性研究，这极大地影响了离心泵振动性能的计算精度。特别针对微含气工况下流体引发的高速泵转子系统耦合振动特性亟需深入研究。本项目拟结合数值模拟、理论分析与实验，基于微含气工况全流场数值计算，建立该工况下考虑温度效应的间隙流体激励力计算模型，构建高速离心泵转子系统耦合运动模型，揭示微含气工况下流体激励力对转子系统耦合振动特性的影响。

High-speed centrifugal pump is the core device of liquid delivery system, which is widely used in aerospace and petrochemical industry. Under the interaction of high rotational speed, fluid excitation force, gear force and couple, the shafting system of the pump shows obvious coupled vibration characteristics instead of transverse vibration. Especially, the fluid excitation force has an important influence on the coupled vibration characteristics. In addition, when the pumping system transports the vaporizable and low-density liquid medium, the medium is easy to precipitate trace gases due to the change of working conditions, which makes the high-speed pump in the micro-gas condition and affects the flow and vibration performance of the pump. Most of the existing research on centrifugal pumps, the influence of micro-air content on the flow characteristics, fluid excitation force characteristics, especially the influence of gap excitation force characteristics is not considered. And the coupled vibration characteristics of the rotor system under this excitation are not investigated, which greatly affects the calculation accuracy of centrifugal pump vibration performance. Studies especially for the fluid-induced coupled vibration characteristics of high-speed pump under micro-gas condition are urgently needed. In this study, combined with numerical simulation, theoretical analyses and experiments, a calculation model considering temperature effect for clearance fluid excitation force is established under the micro-gas condition, while a coupled motion model of high-speed centrifugal pump under this condition is constructed. Moreover, the influence of fluid excitation force on the coupled vibration characteristics of the rotor system under the micro-gas condition are revealed.