含铝固体燃料冲压发动机工作性能分析

Performance Analysis of Aluminized Solid Fuel Ramjet

关键词:  固体燃料冲压发动机  含铝推进剂  燃面退移速率  推力  比冲

Key words:  Solid fuel ramjet  Aluminized propellants  Regression rate  Thrust  Specific impulse

摘要:

为探究含铝固体燃料冲压发动机的燃烧特性和工作性能，基于纳米铝颗粒和端羟基聚丁二烯（HTPB）的混合固体燃料，采用雷诺转捩模型、颗粒表面反应模型和涡概念耗散模型，建立了二维两相湍流燃烧模型；数值计算分析了含铝固体燃料冲压发动机内流场，以及不同含铝质量分数和粒径下的燃面退移速率、推力与比冲。结果表明：发动机的进气条件对颗粒相的燃烧与运动起主导作用；与纯HTPB推进剂相比，添加质量分数为5%的铝颗粒能够提高补燃室压强和温度，增大燃烧室内高温区面积，可使推进剂平均燃面退移速率提高18.53%，发动机推力提高21.37%，密度比冲提高2.38%，适当增加铝颗粒含量或减小粒径，对提高推进剂燃面退移速率、发动机推力和密度比冲具有积极作用。

Abstract:

In order to investigate the combustion characteristics and working performance of aluminized solid fuel ramjet （SFRJ）， a two-dimensional two-phase turbulent combustion model is established based on the mixture of aluminum nanoparticles and hydroxyl terminated polybutadiene （HTPB） using Reynolds transition model， particle surface reaction model and vortex concept dissipation model. The flow field in the ramjet with aluminum solid fuel， and the regression rate of burning surface， thrust and specific impulse with different aluminum content and particle size were analyzed numerically. The results show that the intake conditions of SFRJ play a leading role in the combustion and movement of the particulate phase. Compared with pure HTPB propellant， the addition of 5wt% aluminum particles can increase the pressure and temperature of the afterburner， increase the area of the high temperature zone in the chamber. It also can increase the average regression rate of burning surface by 18.53%， the thrust by 21.37%， and the density specific impulse by 2.38%. Appropriately increasing the content of Al particles or decreasing the particle size can improve the regression rate of burning surface， thrust and density specific impulse of propellant.