对几种间隙流体激振力模型进行分析比较,着重描述了Muszynska模型所揭示的流体激振力的主要特征;并应用Muszynska模型建立了水轮机Jeffcott转子-密封系统非线性动力学模型;通过数值计算分析了系统主要参数对稳定性的影响及转子涡动幅值随转速变化的规律。结果表明当转速超过临界失稳转速时,系统出现小幅度涡动,随着转速的进一步提高,转子的涡动幅值持续增加,最终可能导致碰摩,是转子产生破坏事故的重要原因之一。
With comparison analysis of several models of the fluid exciting force for the clearance of the hy draulic turbines, this paper describes the main characteristics of the fluid exciting force by the Muszynska model. The nonlinear Jeffcott mode of the rotorseal system for the clearance of the hydraulic turbines has been established. The influence of the main parameters on the stability of the system and the characteristic of whirl amplitude are studied with rotation speed of the rotor by the numerical calculation. The results state that when the rotation speed of the rotor reaches the threshold speed, the whirl amplitude of the sys tem begins to appear. With the rapid rotation speed, the amplitude of vibration increases, and the rotorsta tor rubs will be happened to destroy the system. So studying on the fluid excitation of the hydraulic tur bine rotorseal system is important and meaningful.