Investigation on effects of hydrogen addition to the thermal performance of a traditional counter-flow combustor

Abstract

The hydrogen applicability of current gas turbines designed for traditional fuels needs to be improved. The influence of hydrogen addition to the performance of swirling methane-air combustion has been investigated for a counter-flow combustor. The combustor was simulated under certain swirl intensity for a 100 kW micro gas turbine fuelled by methane–hydrogen mixture. The predicted outlet temperature and the measured value based on practical combustors were compared. The effects of air distribution scheme and hydrogen content in fuel mixture on thermal characteristics were analyzed from the perspectives of multi fields and synergy. The results show that the scheme with primary air of 50%, secondary air of 20% and dilution air of 30% leads to an ideal temperature distribution at the exit. With the increase of hydrogen addition ratio, the outlet temperature decreases and the emission of pollutant NOX is controlled within an ultra-low range. When the hydrogen volume content exceeds 20%, the hydrogen addition has a great impact on the field synergy in the combustor, which is beneficial to the uniform temperature distribution at the exit and the relatively low flow resistance. These findings may supply guidance for the redesign and operation of the gas turbine using hydrogen-doped fuels.