The Bottom Row Of The Bottom Of The Device Combustion Flow Field Numerical Simulation Research

In these decades, the Base Bleed Unit (BBU) has been extensively researched due to the advantages of simple structure and high extend range rate etc. In this thesis, based on the background of Base Bleed Projectile (BBP), the numerical simulation with the software FLUENT and theoretical analysis methods were carried out to investigate the base bleed flow with and without combustion. The work presents as follows:Firstly, the computational model of flow with combustion of BBU was established. The base flow field with non-reacting gas and H2-O2combustion was numerical simulated with the Axisymmetric Reynolds-Averaged Navier-Stokes equations. The combustion process was modeled by laminar finite-rate chemistry considering the detailed reacting mechanism of H2-O2. The effects of different parameters such as injection parameter, free stream Mach number, injection total temperature and injection momentum etc, on the base pressure were explored, and the characteristic of base pressure and recirculation region were obtained as well. The results agree well with the experiment.Secondly, the thermodynamic calculation model of base bleed propellant was developed. Based on VB, primary combustion of the propellant was calculated using equilibrium constant method. The results are consistent with CEA results, thus to offer a reasonable inlet boundary.Thirdly, the base flow with combustion assumption of BBP was build. The base combustion system of the base bleed propellant was simplified and replaced by H2-CO combustion system. The2-D Axisymmetric base combustion flow field with and without spinning was investigated using standard k-co turbulence model and Eddy Dissipation Concept (EDO combustion model, and the combustion mechanism consists of nine reactive species and twelve reaction steps. The detailed structure of base flow field and the distribution of combustion components were obtained, and also the effects of these factors such as injection parameter, Mach number and spinning etc, on the base combustion flow were analysed.Finally, based on the SOCBT projectile, the standard k-co turbulence model and EDC combustion model with the same combustion "mechanism, were employed to investigate the3-D base combustion flow field, and the structure of base flow field and the distribution of combustion components in the condition with and without attack angle were also studied.