底排推进剂瞬态泄压工况下燃烧流场特性的数值模拟

针对底排弹出炮口泄压瞬间燃烧失稳问题,建立了AP/HTPB底排推进剂燃烧流场的二维轴对称非稳态模型,通过数值模拟获取了底排模拟装置在瞬态泄压工况下的流场特性。结果表明: 在泄压过程中,燃烧室内压力、密度和温度沿轴向迅速下降,速度沿轴线迅速升高,且各流动参数的变化梯度逐渐减小；底排推进剂燃气的加入导致燃烧室内密度沿径向降低,而温度沿径向升高；燃烧室内压力随时间变化的计算值与实测值吻合较好。

Numerical Simulation of Combustion Flow Field Characteristics of Base Bleed Propellant Under Transient Pressure-release

Aiming at the combustion destabilization during the depressurization of base bleed projectile when propelled out of gun muzzle, a 2D-axisymmetric unsteady model for the combustion flow field of AP/HTPB base bleed propellant was established. The flow field characteristics in base bleed simulator under transient pressure-release were obtained through numerical simulation. Results show that in the pressure-release process, the parameters such as the pressure, the density and the temperature in the combustion chamber decrease quickly along the axial direction, the gas flow rate rises rapidly, and the gradients of various parameters gradually decrease. As a result of the base bleed propellant gas ejecting into the chamber, the density decreases along the radial direction, whereas the temperature increases on the contrary. The calculated pressure varying with time in the combustion chamber agrees well with the experimental data.