Method for Burning Super-Poor Fuel Mixtures in the Combustion Chamber of the Energy Microturbine by Means of theStreamer Discharge

Abstract

The paper considers the problem of increasing fuel efficiency and reducing emissions of gas turbine power plants. The aim of the work is to develop a method for burning extra-lean fuel mixtures. The method of ignition by a streamer high-frequency discharge was considered. The discharge was ignited in the presence of the resonator by a quasioptical beam of microwave radiation with a wavelength of 8.9 - 12.5 cm. The resonant ignition method was 20 to 100 times more energy efficient than laser and plasma ignition methods. The method combines an experiment and mathematical modeling of a streamer discharge. The result was the ignition of an extremely lean mixture with an air fuel rate of more than 30. A regime of flameless combustion was detected, when a flame wasn’t visible, but heat generation as a result of a chemical reaction has occurred. Stable combustion of the lean mixture was obtained at a flow rate of up to 30 m/s. These conditions simulated combustion in a tubular combustion chamber. A pulse with a wavelength of about 2.5 cm couldn’t create a streamer discharge and couldn’t be used for multi-point ignition. Burning front speed was 2-4 times higher than in spark ignition. Traditional low-emission combustion chambers have large dimensions and a very complex design. This makes it difficult to use them in microturbine. The application of the method described in the article makes it possible to create significantly more compact low-emission and highly economical combustion chambers for power gas turbine plants.

Keywords

• microturbine