Vibration Analysis of a large Capacity Drainage Pump Station by Using Finite Element Method

摘要

The vibration propagation characteristics of a large capacity drainage upmp statioin, which is approximately 99 meters in length, 40 meters in width and 34 meters in height, are analyzed by using finite element method in a frequency range of 0-100Hz. The results are compared with the measured ones and they show good agreement. The factors that may influence the accuracy of analysis are investigated. It is demonstrated that (1) the spring constants of the ground have influence only on the results of analysis at low frequency, so that the ground can be modeled as a clamped boundary condition when doing response analysis at high frequency, (2) the damping ratio is frequency dependent and it does not have much influence on the results of analysis at locations near the excitation source, but it has great influence on those at locations away due to the very high mode density. Furthermore, it is demonstrated that the responses at locations near the excitation source can be calculated by analyzing only one portion of the structure.