Ideal cycle analysis of a pulse detonation engine

Abstract

Pulse Detonation Engine (PDE) is expected to be one candidate for the next generation of high performance propulsion engines and power plants. The need for heavy air compression in common gas turbines could be eliminated in PDEs, allowing the operation with fewer compressor stages. This advantage would yield higher thermal efficiency and decrease the size of the engine. So, PDEs could be proposed as an alternative to gas turbines especially for small commercial power generation plants. Cycle analysis would be an excellent tool to compute and analyse the performance of PDE without the necessity of expensive experimental tests. In the current study, the effects of fuel types and frequency of a PDE on the thermal efficiency through thermodynamic cycle analysis is evaluated. The generic models for the cycle analysis are developed by Matlab. The Humphrey, ZND and Brayton cycles are adopted for this analysis. Thermal efficiency of Biogases for its less emission characteristic is studied in an ideal cycle against Hydrogen, Methane and Propane. It is concluded that the Biogas could be an appropriate fuel for theoretically PDE studies. To find a relation between thermal efficiency and frequency, at constant geometry, in two different attempts, the relation between thermal efficiency and detonation speed, and that of frequency and the velocity of filling and purging are studied. It’s seen a direct relation between thermal efficiency of PDE cycle and its frequency cannot be found.