Energy and exergy analysis of pulse detonation combustor and pulse detonation turbine engine cycle

Abstract

As a kind of pressurized combustion, pulse detonation combustion brings many possibilities for the improvement of aero-engine performance.In this paper, energy and exergy analyses of pulse detonation combustor (PDC) and pulse detonation turbine engine (PDTE) cycles based on unsteady analysisare conducted. A simplified exergy flow model is proposed to describe the exergy flow of PDC under different inlet conditions, and based on this, the exergy efficiency of PDC is compared with that of an isobaric combustion chamber. In addition, the energy and exergy flows of ideal and real PDTE cycles are analyzed, and the cycle thermal and exergy efficiencies under different inlet conditions are obtained. The results show that the exergy efficiency of PDC is higher than that of an isobaric combustion chamber from an inlet pressure ratio of 3–45, but the efficiency improvement decreases from 13.2 % to 7.2 %. The thermal efficiency of the ideal PDTE cycle is higher than that of the Brayton cycle, but the efficiency improvement decreases from 78.2 % to 4.7 %. The irreversible losses in the real process will lead to energy loss during compression and expansion processes in the PDTE cycle, thus reducing its exergy efficiency and thermal efficiency.

Keywords

• Energy
• Exergy
• Pulse detonation
• Thermal efficiency