ALTERNATIVE FUELS IN GAS TURBINE APPLICATIONS: A SIMPLE METHOD FOR ASSESSING THE INFLUENCE OF FUEL ON PERFORMANCES

摘要

Gas turbines have by essence access to a broad range of primary energies. This advantage is essentially exploitable by the Heavy Duty branch which, thanks to moderate compression ratios, robust mechanical designs and versatile combustion systems, can utilise a wide series of commercial and process by-products fuels: natural gas, petroleum distillates, gasified coal or biomass, gas condensates, ash-forming fuels, alcohols etc. In this context, a thorough knowledge of the many-facetted fuel/machine interdependency, which seems insufficiently covered by the existing literature on gas turbines, is of prime interest. This paper is devoted to the thermodynamic aspects of fuel influence. It offers: (i) a review of the main primary energies accessible to stationary gas turbines, (ii) a new, differential method for assessing the impact of fuel on machine thermodynamics, with original equations accounting for the changes in power output, efficiency and exhaust heat.