Numerical investigation of flame propagation and performance of obstructed pulse detonation engine with variation of hydrogen and air

Abstract

Pulse detonation engine is a new technique of supersonic wave propagation and stands for high impulsive thrust. The objective of the present investigation is to analyze the detonation wave characteristic of a hydrogen-air mixture in the pulse detonation engine (PDE) having obstacles of blockage ratio 0.5. The three-dimensional reactive Navier-Stokes equations with realizable k − ɛ turbulence model are used to simulate the propagation of combustion flame. The reaction rate of excess hydrogen and excess air is modeled by reduced single-step chemical reaction model and simulated using ANSYS software FLUENT 14.0 code. The simulation results of the shock wave overpressure, deflagration-to-detonation transition run-up distance of different flames and flame velocities are reported at initial boundary condition of 0.1 MPa pressure and 293 K temperature. It has been observed that the obstacles create turbulence in the propagating flame and form strong Mach stems of high temperature, resulting in reduction in accelerated flame run-up length. However, the normalized detonation flame run-up distance increases as the mass of fuel increases in the mixture. Thus, the performance of PDE combustor was observed 4.46% at high overpressure generated by excess fuel (ϕ = 1.3).

A State of Art Review on Thermodynamics Performance Analysis in Pulse Detonation Combustor

“…They found that Schelkin spiral accelerate the flame propagation. Alam et al [63] numerically studied on flame propagation in obstructed pulse detonation combustor with hydrogen-air mixture. They found that performance is increase up to 4.46% and this value increase for 𝜙 = 1.3.…”

Numerical Investigation on Pulse Detonation Engine Performance Under Different Equivalence Ratio

“…In literature, many studies include ignition and DDT processes for the propagation of the detonation wave in the pulse detonation engines. Obstacle [14][15][16][17][18][19][20][21][22] and Shchelkin sphiral [23][24][25][26][27] are used as DDT mechanisms. In numerical studies on the flame's transition into a detonation wave, the filling stage is not included, and the fuel-oxidizer mixture is defined as premixed in the detonation tube.…”

“…In numerical studies on the flame's transition into a detonation wave, the filling stage is not included, and the fuel-oxidizer mixture is defined as premixed in the detonation tube. Alam et al [14] investigated the effects of different equivalence ratios on the DDT transition step and the detonation wave propagation using a pulse detonation engine configuration modeled with obstacles having a 0.5 blockage ratio. Tangirala et al [17] utilized ideal and benchmark tube pulse detonation engine configurations in their numerical studies, examining the DDT and blowdown stages in experimental work.…”