Large Eddy Simulation of Detonation Combustion and Combustion Efficiency of Liquid and Gaseous Fueled Pulse Detonation Combustors

Abstract

The numerical research work is carried out for the deflagration and detonation combustion process and pollution formation for a stoichiometric (ϕ = 1) mixture of zero carbon and a hydrocarbon fuel–air mixture in the pulse detonation combustor. Furthermore, the combustion efficiency also has been analyzed for hydrogen, kerosene and octane fuel–air mixtures inside the combustor. The SIMPLE algorithm with the finite volume discretization method is used for laminar finite rate chemistry with volumetric reaction in Ansys Fluent platform. The LES turbulence model is used to carry out calculations of the reliable and repeatable detonation wave in the pulse detonation combustor near thin boundary layer formed by the Shchelkin spiral. From the simulation, the detonation wave velocity of 2000 m/s and the reaction enthalpy of 71.4 MJ/kg are obtained for hydrogen–air combustion, which is higher as compared to those in kerosene and octane fuel–air combustion. The minimum pollutant number of 0.00000479 is obtained for hydrogen–air detonation and this magnitude is lower as compared to that for kerosene and octane–air combustion. Furthermore, the maximum combustion efficiency of 87% is obtained for hydrogen–air combustion in the detonation combustion process, which is comparatively higher than that for kerosene and octane fuel–air mixtures. Also, the combustion efficiency is more in detonation combustion for aforesaid liquid and gaseous fuel–air mixture combustion as compared to the deflagration combustion process.