Development of a Low-Emission Combustor for a 100-kW Automotive Ceramic Gas Turbine (III)

Abstract

A low emission combustor, which uses a prevaporization-premixing lean combustion system for the 100 kW automotive ceramic gas turbine (CGT), has been subjected to performance tests. Now a second combustor prototype (PPL-2), which incorporates improvements intended to overcome a flashback problem observed in an initial combustor prototype (PPL-1), is tested. The PPL-2 has been designed and built, so that it will substantially expand the stable combustion range. The improvement is accomplished by increasing the air distribution ratio in the lean combustion region to avoid flashback, providing a uniform flow velocity through the throat area and also by diluting the boundary layer so as to suppress flashback. Test results of the PPL-2 combustor show that it expands the flashback limit without affecting the blow out limit and is able to cover the stable combustion range need for the 100kW CGT.

Development of a Low-Emission Combustor for a 100-kW Automotive Ceramic Gas Turbine: II

“…The right-hand column of the table shows the measures that were incorporated in the preliminary combustor design with the aim of attaining the performance targets. The design details of typical measures were described in the previous report [2]. For instance, in order to promote better fuel atomization and mixing, a swirler and a louver were installed at the inlet to the prevaporization tube and the tube was positioned tangentially to the longitudinal axis of the lean combustion section.…”

“…In a previous study of three types of low-NOx combustion systems, it was found that a prevaporization-premixing lean combustion system was a promising practical combustor candidate for meeting the gasoline engine passenger car emission standards [1]. This combustion system was therefore adopted to design and engineer a prototype ceramic combustor in the COT development project [2].…”