Simulation methods used to analyze the performance of the GE PG6541B gas turbine utilizing low heating value fuels

The ability to model the behavior of gas turbine engines is critical in economic, thermal and condition monitoring studies. This is especially true for applications involving alternative fuels, such as biomass and coal derived fuels, where the engine operates far from its ISO performance ratings found in publications such as Gas Turbine World. This paper presents an approach taken for modeling a Frame 6 engine and its control system given a fairly limited set of available data. The approach and model are tested against vendor cycle deck data for both natural gas and a low-Btu biogas fuel. The model is then used to predict behavior of the Frame 6 engine fired by another biomass-derived fuel over a range of ambient and loading conditions. Issues relevant to this fuel/turbine combination and limitations of the modeling method are discussed. The engine model was developed using the individual turbomachinery component modules in the GateCycle analysis software package. The model is based on pressure and flow matching of the turbomachinery components. It includes a compressor map, a relationship to simulate a turbine `map`, and cooling flow calculations. Regardless of the accuracy of the modeling methods, it is always advisable to verify calculations based onmore » aftermarket sources with manufacturer`s values before using the predictions for commercial decisions.« less