旋轉壓縮機是一種廣泛應用於房間空調器中的小型旋轉機械。由於受到空間的限制,其結構非常的緊湊。細長的曲軸同時受到不平衡品質的離心力和壓縮氣體的橫向載荷,同時兩個支撐軸承座為一端固定的薄壁結構。所以,其轉子軸承系統的特點是柔性、具有小品質和承受橫向的大動載荷,是一類非常特殊的轉子軸承系統。本文將轉子軸承系統作為一個動態的非線性流固耦合問題求解。把轉子與軸承座當成柔性子系統,建立了有限元模型;對油膜Patir-Cheng平均流模型,利用矩形單元對油膜進行離散,建立油膜求解有限元模型。利用Newton-Raphson方法對耦合方程進行了求解。由於考慮了系統的柔性及其對油膜的影響,可以準確的評價可靠性、優化系統結構。最後,在分析探討部分,本文針對單缸變頻壓縮機,討論了在低轉速和高轉速的情況下,不同平衡塊配置方案對轉子軸承系統的影響。
A special rotor-journal bearing system under large and dynamic loads is studied in this paper, which originates from the rotary compressor. It's a flexible system because of the slender shaft and two thin wall bearing housings.It is considered as a fluid-structure interaction problem. The finite element method is applied to approach the rotor system, bearing housings and nonlinear fluid films. The coupling equations are resolved with Newton-Raphson method. Based on the method, the dynamic behaviors of the system with different balancing configurations at different speeds are analyzed.