DMCP燃料机理及其在燃烧数值模拟中应用

DMCP fuel mechanism and its application in numerical simulation of combustion

高能量密度燃料具有更高的体积热值,其机理研究对发动机燃烧过程模拟具有重要意义。针对火箭发动机使用的高能量密度燃料1,2-二环丙基-1-甲基环丙烷(DMCP),本文构建了其燃烧反应详细机理,并采用直接关系图法(DRG)以及基于DRG的敏感度分析方法(DRGASA),以燃料点火延迟时间为指标进行简化,得到了40物种133反应的简化机理。在当量比0.5-2.0,压力1.0-20.0 atm,温度900-1300 K的宽工况范围内,通过动力学模拟进行了简化机理的验证,点火延迟时间平均误差为12.59%,层流火焰速度平均误差为6.64%,表明简化机理的合理性。将该简化机理用于火箭发动机模型燃烧室的数值模拟,并与总包机理的数值模拟对比,结果表明高精度简化机理模拟的流场合理,而总包机理对温度的预测偏高,表明该简化机理可用于发动机燃烧模拟。

High-energy-density fuels(HED fuels) have higher volumetric calorific values,and their mechanism studies are important for engine combustion process simulation.For the HED fuel 1,2-dicyclopropyl-1-methylcyclopropane(DMCP) used in rocket engines,the detailed mechanism of its combustion reaction is constructed in this paper,and the reduced mechanism of 40 species 133reaction is obtained by using the direct relationship graph method(DRG) and the DRG-based sensitivity analysis method(DRGASA) with the fuel ignition delay time as the index.The reduced mechanism was verified by kinetic simulations in a wide operating range of 0.5-2.0 equivalence ratio,1.0-20.0 atm pressure and 900-1300 K.The average error of ignition delay time was 12.59%and the average error of laminar flame velocity was 6.64% indicating the rationality of the reduced mechanism.The reduced mechanism was used in the numerical simulation of the rocket engine model combustion chamber and compared with the numerical simulation of the global mechanism.The results show that the flow field simulated by the high-precision reduced mechanism is reasonable,while the global mechanism has high prediction of the temperature,indicating that the reduced mechanism can be used in the engine combustion simulation.