Performance Evaluation of a Variable Geometry Gas Turbine in a CHP Plant

Abstract:

This study is to develop mathematical models and evaluate the performance of a gas turbine with variable geometry compressor working in a CHP plant. A single shaft gas turbine plant can maintain the exhaust gas temperature if the load is not below 50 % of the full load by simultaneously regulating the compressor variable vanes position and fuel flow. For load less than 50% the engine is running to meet the power demand. This is achieved by controlling the fuel flow and air bleed at the downstream of the compressor to avoid surge formation while variable vanes are opened fully. To accommodate change of compressor parameters during variable vanes re-stagger correction coefficients are introduced. A behavior of a 4.2 MW gas turbine performance was evaluated. The effect of variation of load and ambient temperature on the gas turbine specific fuel consumption, temperature, pressure ratio, variable vanes opening and efficiency were examined. Comparison between the field data and simulation results demonstrate good agreement. The off-design calculation was done by in-house developed program in MATLAB environment.

• Periodical: Applied Mechanics and Materials (Volume 798)
• Pages: 59-63
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.798.59
• Online since: October 2015
• Authors: Aklilu Tesfamichael Baheta*, S.I. Gilani, Shaharin Anwar Sulaiman
• Keywords: Gas Turbine, Modeling, Part Load, Performance Evaluation, Variable Vanes

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