隔层式多脉冲发动机点火延迟数值仿真研究

Numerical Simulation of Ignition Delay for Elastomeric Barrier Multi-pulse Solid Rocket Motor

隔层式多脉冲发动机点火过程较常规发动机有很多不同,为获得端燃型隔层式多脉冲发动机的点火延迟特性及其影响因素,建立物理和数学模型,采用MpCCI耦合器作为FLUENT与ANSYS的数据交换平台,模拟点火燃气填充隔层和隔层变形过程;采用FLUENT计算多脉冲发动机火焰传播过程及填充过程。计算结果表明,与传统固体火箭发动机相比,在相同点火药量的情况下,多脉冲发动机的点火延迟大大增加;推进剂燃速越高,点火延迟越小;燃烧室自由容积越大,点火延迟越大;隔层材料对点火延迟影响较小。可以通过适当加大点火药量和提高燃速来减小点火延迟。

The ignition process exists differences between elastomeric barrier multi-pulse solid rocket motor and common motor.In order to gain further insight into the nature of the ignition delay of elastomeric barrier multi-pulse solid rocket motor,physical and mathematical models were built,and MpCCI coupler was adopted as the data exchange platform of FLUENT and ANSYS to simulate the process of filling up the barrier with gas and the barrier deformation,and FLUENT was used to calculate the process of flame transmission and the filling process.The research supports the fact that the ignition delay increases more greatly in the multi-pulse solid rocket motor than in the traditional solid rocket motor,under the condition of the same ignition mass.The research also shows that the higher propellant burning rate goes,the shorter ignition delay becomes,while the larger of the free volume,the longer ignition delay becomes.However,the research indicates that the material of the barrier affects the ignition delay slightly.In conclusion,ignition delay can be diminished through increasing ignition mass or increasing burning rate.