Performance Enhancement of Gas Turbine Engines Topped With Wave Rotors and Pulse Detonation Combustors

Abstract

Abstract In the present research work, a novel method of integrating the conventional gas turbine engine with a Wave Rotor (WR) and a Pulse Detonation Combustor (PDC) is proposed to increase the specific work and thermal efficiency of the engine. Two gas turbine engine configurations, viz. (i) Baseline engine topped with a wave rotor and a steady flow combustor (BWRSFC), and (ii) Baseline engine topped with a wave rotor and a pulse detonation combustor (BWRPDC), have been analyzed with and without recuperative systems. In the case of BWRPDC, the principle of quasi-steady expansion of detonation products through a nozzle into the ejector to entrain and eject the bypassed compressed air along with detonation products exhausted from WR, and a steady expansion of remained detonation products of PDC through the WR to provide the required energy transfer to further compress and supply the un-bypassed compressed air to PDC, has been considered. The pressure of the ejected gases from the ejector will be 25% to 35% higher than the air pressure delivered by the compressor of baseline engine and can develop more specific work with enhanced thermal efficiency when expanded in the turbine. A computer code is developed in MATLAB to simulate the engine performance with and without recuperation / regeneration. For thermodynamic calculations, two un-recuperated micro-turbine engines called C-30 and C-60 made by Capstone Turbine Corporation are considered. C2H4/air is taken as the fuel-oxidizer. The variation in specific work, and thermal efficiency with wave rotor pressure ratio has been investigated for C-30 and C-60 engines. Further, a sensitivity analysis of the performance of BWRPDC with a change in the Entrainment Coefficient (EC) of ejector has also been made.