Structural Dynamic Behavior of Frame 9E GTG Module for LNG Plant

Abstract

Lecture 9: The traditional onshore installation of heavy duty gas turbine generator trains, especially for power >80MW, is stick built on heavy and rigid concrete block foundation. The challenge of modularization is that vibrations have to be transferred to concrete through structural steel, nevertheless implementing vibrations’ acceptance criteria that were developed for direct concrete foundations. This novel concept of modularization needs a deeper dynamic analysis at system level to ensure that flexible structure modes are not excited at any operating condition; with respect to this subject, the Appendix A to this lecture is a dynamic analysis tutorial for turbomachinery modules, having the aim to describe the process and the tools to be used for purpose, based on author’s experiences and lessons learnt also during the experiment described herein. The results of the dynamic analysis made on a complete system including module, foundation and sub foundation in “Full Speed No Load Test” (FSNL) configuration have been for the 1st time compared with field measurements.