输送管壁温对膏体推进剂燃速的影响

膏体推进剂作为一种新型特种推进剂，具有广阔的应用前景。膏体推进剂燃速直接影响发动机内弹道性能，研究输送管道壁温对推进剂燃速的影响具有重要意义。采用幂律本构方程表征膏体推进剂粘度，Arrhenius方程表征温度对粘度影响，并利用中心有限差分格式对控制方程进行离散。对恒定壁温下的膏体推进剂与管道间传热特性进行数值仿真，并进行了数值验证。结合仿真结果，并借鉴固体推进剂初温与燃速关系，分析了热管道内膏体推进剂燃速特性。结果表明：近壁面加热层厚度随入口速度增高而减小，随管径增大而增大，管内膏体推进剂平均燃速较入口温度条件下有所提高，同时，高温壁面条件下，近壁面推进剂温度高于爆发点，需要考虑管道内的防窜火措施。

Influence of wall temperature of feed line on pasty propellant burning rate

As a new kind of propellant, pasty propellant has a bright prospect in application. The burning rate of pasty propellant has a direct influence on interior ballistics of engines, so it is very im- portant to study the influence of wall temperature of feed line on the pasty propellant burning rate. The power-law constitutive equation and Arrhenius equation are adopted to character the viscosity of pasty propellant and the influence of temperature on the viscosity respectively. The central finite dif- ference scheme is used to disperse the control equations. After validating the numerical method, the numerical simulation on the characteristic of the heat transfer between the pasty propellant and feed line were carried out at constant wall temperature. According to the relationship between initial temperature and burning rate of a solid propellant, the burning rate characteristics of the pasty propellant in a hot feed line were analyzed based on the numerical simulations. The result shows that the heated layer thickness close to the wall decreases with the augment of inlet velocity and increases with the augment of feed line diameter. The average burning rate of the pasty propellant in feed line is higher than that at inlet temperature. Meanwhile, as the wall is at high temperature, the propellant temperature close to the wall is higher than that of its break out point, and it is necessary to take into account the anti-backfire methods.