Ignition Characteristics on the Annular Combustor With Rotating Fuel Injection System

Abstract

An experimental study was performed to investigate the ignition characteristics on the annular combustor with rotating fuel injection system. The combustor was tested in KARI (Korea Aerospace Research Institute) combustor test facility. As the results of the test, equivalence ratio of lean ignition limit is 0.15 at 7,300 rpm and 0.08 at 10,400 rpm respectively. Combustion efficiency is gradually increased from 99.1% to 99.62% with increasing shaft speed from 15,000 rpm to 30,000 rpm. Over than 30,000 rpm, the combustion efficiency is not changed and kept constant. From the ignition and combustion test, ignition process of this annular combustor is mainly governed by the shaft speed. To understand the relationship between the spray characteristics and shaft speed, droplet size was measured by using PDPA system. In this spray test, Sauter mean diameter (SMD) largely depends on the shaft speed. SMD is changed from 73 μm to 42 μm with increasing the shaft speed from 5,000 rpm to 20,000 rpm.