舰用主汽轮机汽缸动刚度分析研究

Analysis on the Dynamic Stiffness of Cylinder of Marine Main Steam Turbine

为准确计算主汽轮机低压缸整体结构的动刚度,选取最能反映模型整体位移的低压缸底部中心处为单位激振力的加载点,考虑模型在单位激振力作用下的动态响应,并与在前后轴承座处加载单位激振力时的动态响应进行对比分析。研究表明,在低压缸底部中心处加载激振力能够较好地反映整体模型的振动特性,能较精确地得到整体模型的动刚度,是可行且有效的。

In order to compute the dynamic stiffness of low-pressure cylinder of the marine main steam turbine accurately, the center of the bottom of the cylinder was chosen as the loading point for a unit exciting force, as this position could best represent the displacement of the whole cylinder model. The dynamic response under such load case was compared to that under another load case with the unit exciting force acting on bearing supports. The results show that the fist load case can be a better representative of the vibration of the whole cylinder and it is a practical and efficient loading way to obtain the dynamic stiffness more accurately.