10 - Performance, Performance Testing, and Performance Optimization

Abstract

Gas turbine performance, performance verification, and maintenance are irrevocably linked in an end user's world. Gas turbine (GT) performance verification (testing) is done at several levels. The testing of new GTs, done at the original equipment manufacturer's (OEM's) facility, may be witnessed by end-user reps. Sometimes functional, no-load tests are conducted. Load testing is far more expensive than functional testing but critical in cases where the application or engine model is in some way different from previous applications. When an existing system needs to be optimized, the best designer for the project may or may not be the OEM: this is the end user's choice. An independent firm may or may not work with the OEM's knowledge and assistance. In an operational context, a GT system needs to be monitored for performance degradation. Frequently, the cause of performance degradation is flow blockage, either in the compressor (potentially due to fouling) or turbine (potentially due to component deterioration or failure). Generally, unless components are damaged permanently, compressor performance can be recovered with washing the compressor. The washing can be online or offline, at operating speed or reduced speed, and done with water plus additives, cleaning fluid, rice husks, or other mildly abrasive solid material (that still will not damage metal airfoils).