耦合凝相-气相动力学机理的二硝酰胺铵燃烧模型

An Ammonium Dinitramide Combustion Model with Coupled Condensed-Gas Phase Kinetics Mechanism

为了研究二硝酰胺铵ADN(Ammonium Dinitramide)固体推进剂燃烧物理化学过程并预测其燃烧特性,建立一个耦合凝相-气相动力学机理的ADN燃烧模型。该模型基于凝相与气相的总连续方程、组元连续方程、能量守恒方程及有限速率化学动力学方程而建立,并引入多组元系统状态方程封闭方程组。模型中包含34种组元,1个固相(凝相)ADN分解总化学反应和165个气相细节(基元)化学反应,并使用以温度函数表示的物性参数进行计算。应用气相燃烧模型对0.6 MPa下ADN燃烧火焰温度、组元摩尔浓度分布进行预测;应用耦合凝相-气相的燃烧模型对0.2 MPa^36 MPa压强区域内柱状端燃ADN推进剂燃速、燃烧表面温度进行预测,计算结果与文献报道试验数据较吻合。说明该燃烧模型能够较准确描述ADN气相燃烧波结构和ADN固体推进剂燃速特性。

A numerical calculation medel with coupled condensed-gas phase kinetics mechanism was developed to study the physical and chemical processes involved in ADN combustion and predict the characteristics of combustion wave. The model was based on the conservation equations of mass, species concentration and energy for both condensed phase and gas phase, and takes into account finiterate chenticul kinetics and real thermophysical properties. At last, the equation of slate for a mttlticomponent system was employed to close the equations. A chemical kinetics scheme, containing totally 34 species, 1 global ADN decomposition reaction in condensed phase and 165 detailed reactions in gas phase, was established and employed in the model. The gas phase mechanism model was applied to predict species mole fraction profiles and temperature profiles in ADN gas phase flame at 0.6MPa. The coupled condensed-gas phase mechanism was employed to predict ADN monopropellant burning rate and burning surface temperature at pressure range of 0.2- 36 MPa. The agreements btween calculation results and experimental data are satisfying. The results indicate that the coupled condensedgas phase kinetics mechanism can predict ADN combustion in reasonable accurately.