Life Cycle Analysis and Optimisation of a Combined Cycle Based on the Industrial Trent 50

In cooperation with Rolls-Royce and Lund University, a combined cycle power plant was modelled, simulated and optimised in the new software framework, the GTPOM tool, developed through the recent EC FP5 programme. The goal was not only to calibrate its component models but also to show how this new tool can be used. This paper presents the gas turbine and combined cycle whole plant modelling and its life cycle cost optimisation within the GTPOM tool. In addition, this paper discusses the software tool bearing in mind that the existence of other commercially available software packages for the purpose. The other thermal engineering software package referred in this project is a product of Thermoflow Inc and is a combination of three software modules, GTPRO, GTMASTER and PEACE. In this project, data from this package was used to calibrate the CCGT plant model in the GTPOM tool. Rolls-Royce Industrial Trent 50 gas turbine was modelled in the GTPOM tool with the abilities to calculate both designpoint and part-load performance for given ambient temperature and exhaust loss. The CCGT power plant with a 2-on-1 configuration was modelled in the GTPOM tool. The component model library developed in the GTPOM project was used, however the component models were modified and improved through calibrations with the reference GTPRO data. The life cycle cost and through life economic parameters of the CCGT whole plant in GTPOM have also been analysed, and then this whole plant model was used as the non-optimised benchmark model for a study in which the model was optimised in the GTPOM tool using a GA optimiser in order to maximise the Internal Rate of Return (IRR). NOMENCLATURE Abbreviations CCGT Combined Cycle Gas Turbine DLE Dry Low Emission EC European Commission GA Genetic algorithm GT Gas Turbine GTPOM Gas Turbine Plant Optimisation HP High Pressure HRSG Heat Recovery Steam Generator IP Intermediate Pressure IRR Internal Rate of Return LMTD Logarithmic Mean Temperature Difference LP Low Pressure PEACE Plant Engineering and Construction Estimator ST Steam turbine Designations C Correction factor for number of tube rows h Specific enthalpy mf Mass Flux Pr Prandtl number Re Reynolds number x1,2,3,4 Steam turbine coefficients Y ST output α Heat Transfer Coefficient ε Ratio of total surface area to tube surface area INTRODUCTION When a gas turbine is used to produce electricity the heat loss from the exhaust is not negligible. One way to use this waste heat is to combine the gas turbine cycle with one more thermal cycle, like a steam cycle. The total efficiency achieved is then higher than that of one cycle alone. The cycle that is