Development of a new lean burning combustor with fuel film evaporation for a micro gas turbine

摘要

The present paper describes a new burner for a micro gas turbine utilizing the lean premixed pre-vaporized combustion. Due to low pressure and low combustor inlet temperature, caused by the thermodynamic cycle conditions chosen, the liquid fuel is evaporated on a hot surface since compressor air temperature is too low for an intense evaporation of a fuel droplet spray. The concept is based on the reverse flow of hot combustion gases along the outer surface of an evaporator tube. The liquid fuel film on the inner surface of the tube is evaporated by heat transferred from the hot combustion gases through the tube wall. The combustor wall is a multi-layered assembly consisting of a ceramic inner liner, a compliant layer, and the outer metal casing. This design allows almost adiabatic combustion to be established. The design process of the combustor is supported by comprehensive numerical studies of the isothermal and reacting flow. The vortex flow of the burner, which provides for flame stabilization, is described in detail. First experimental tests have been conducted. Measured pollutant concentrations of the exhaust gases meet international standards and demonstrate the great potential of the new combustor. (C) 2003 Elsevier Science Inc. All rights reserved. [References: 14]