Effects of swirler blade angle and actuator applied voltage on combustion characteristics and cooling effectiveness

Abstract

This paper investigated effects of swirlers with blade angles and applied voltage of plasma actuators on combustion and wall temperature of a Can - type gas turbine combustor. Results show that large blade angle of the swirler is beneficial for the mixing of fuel and air, which improves uniformity of the outlet temperature distribution and reduces CO emission but results in temperature rise of the wall. Pattern factor reflects uniformity of the temperature distribution at the outlet of the combustion chamber, and a small value of the pattern factor means a good distribution uniformity. In this paper, the minimum pattern factor is 0.45 when the blade angle of the swirler is 55°, which means the best uniformity of temperature distribution at combustor outlet. Compared with the worst results with a 40° blade angle, the pattern factor for the blade angle of 55° decreases by 66.4%. CO emission decreases with the increase of the blade angle. Compared with the maximum value of CO emission for a 40° blade angle, reductions of CO emission are 67.6%, 95.9% and 99.6% with the blade angles of 45°, 50° and 55°. It is found that CO emission decreases by 1.3% and pattern factor increases by 2.2%, when the blade angle of the swirler changes from 55° to 60°. When the applied voltage changes from 0 kV to 8 kV and 16 kV, cooling effectiveness increases by 3.2% and 0.7%. Cooling effectiveness decreases by 2.9% when the applied voltage increases from 0 kV to 24 kV.