Leila Chennaoui

General Method for the Development of Gas Turbine Based Plant Simulators: An IGCC Application

An Energy Conversion Power Plant Simulator development is presented. The various aspects related to the identification of the problem to be solved (cycle calculation, component sizing, off-design component behaviour, components matching and Plant part load analysis) are discussed. Mathematical aspects are illustrated and the components physical models are discussed. Examples for validation purposes are shown. An application to the development of a Generic 300 MW F Class Gas Turbine to be fed with H2 Rich Syngas produced by an IGCC is illustrated.Copyright

Impact of Fuel Flexibility Needs on a Selected GT Performance in IGCC Application

As part of a European Union (EU) funded H2-IGCC project, a baseline IGCC power plant was established; this was presented at the ASME Turbo Expo 2011 (GT2011-45701). The current paper focuses on a detailed investigation of the impact of using various fuels considering different operating conditions on the gas turbine performance, and the identification of technical solutions for the realization of the targeted fuel flexibility.Using a lumped model, based on real engine data, compressor and turbine maps of the targeted engine were generated and implemented into the detailed GT model made in the commercial heat and mass balance program, IPSEpro. The implementation was done in terms of look-up tables. The impact of fuel change on the gas turbine island has been investigated and reported in this paper. Calculation results show that for the given boundary conditions, the surge margin of the compressor was slightly reduced when natural gas was replaced by hydrogen-rich syngas. The use of cleaned syngas instead of hydrogen-rich syngas resulted in a considerable reduction of the surge margin and elevation of the turbine outlet temperature (TOT) at design point conditions, when keeping the turbine inlet temperature (TIT) and compressor inlet mass flow unchanged. To maintain the TOT and improve the surge margin, when operating the engine with cleaned syngas, a combination of adjustment of variable inlet guide vanes (VIGV) and reduced TIT was considered. A parameter study was carried out to provide better understanding of the current limitations of the engine and to identify possible modifications to improve fuel flexibility.Copyright

Expander Models for a Generic 300 MW F Class Gas Turbine for IGCC

Gas Turbines (GTs) for large IGCC plants need some modifications because, usually, they have been developed to be fed with Natural Gas (NG) while the Syngas from the IGCC has a lower Low Heating Value (LHV). As a consequence, the larger flow in the expander raises the compressor exit pressure, producing some instability risks.One of the possible options consists in the modification of the Expander Flow Functions to accommodate the input pressure in a safe range. The above option modifies also the hot surface blade wall temperature with no changes in cooling flows.In this paper flow path data, average blade temperatures, cooling flows and global performance for the Reference GT (RGT) fed with CH4 and for the modified GT fed with syngas (H2R-GT) are reported and compared.The changes in the stagger angles to accommodate the Expander Flow functions for stable GT conditions are presented and results widely discussed.Copyright