Performance evaluation of a gas turbine cycle with a pulse combustion system

This paper presents a comprehensive analysis of the effect of a pulse combustion system an the performance of a gas turbine cycle. The advantages of pulse combustors are numerous. The heat transfer is enhanced by the large oscillations resulting in the flowfield within the combustion zone. These oscillations arise from intrinsic combustion driven instabilities, similar to those that occur in rocket motors. The enhanced heat transfer means that a smaller combustion chamber (furnace) can be used to provide the same energy output. Moreover, a reduction in the No, level in the exhaust gases can be obtained without additional pollution control. It is well known that the gas turbine requires constant pressure combustion process. The efficiency of gas turbine increases with the maximum possible pressure to a certain value and then decreases due to the work consumption in the compressor. in other hand, the literature showed that the efficiency of a constant pressure thermodynamic cycle is generally lower than of a constant volume cycle working at the same maximum combustion pressure. The purpose of this paper, is to analyze theoretically the effect of pulse combustion system on the performance of a gas turbine cycle so that the resultant changes in performance can be estimated without experiment. In addition, this paper investigates the utilization of converting part of chemical energy of fuel into pressure energy in the combustion chamber of a gas turbine utilizing a pulse combustor. A computer code has been written to evaluate the cycle performance, thermodynamic characteristics of the cycle during operation as compared with a conventional cycle. The study describes the influence of the maximum possible pressure rise in combustion chamber, the heat addition ratio, maximum temperature and compressor pressure ratio on the performance parameters such as fuel consumption, net work output, excess air factor and thermal efficiency.