针对喉栓式可调喷管,建立了几何喉部面积计算模型、理论推力模型以及三维仿真模型,对喷管内流场进行了数值模拟,研究了几何喉部面积、出口质量流率、喷管推力随喉栓位置的变化规律,对比发现理论推力与数值模拟计算结果相差较大,因此对推力模型进行了优化。首先建立了气动等效喉部面积的计算方法,研究了气动等效喉部面积随喉栓位置、工况的变化规律,优化了等效喉部面积计算模型,能较好拟合气动喉部面积随喉栓位置的变化情况。在此基础上,针对喉栓运动后期,喷管处于过膨胀状态时的推力模型进行了二次修正,优化后的推力模型与仿真结果相吻合。最后进行了喷管冷气推力测试,获得了不同喉栓位置和入口压强下的喷管推力,验证了推力模型的准确性。

The geometric throat area calculation model, theoretical thrust model and 3-D simulation model are established for the pintle control thrust nozzle. Through the numerical simulation of the flow field in the nozzle, the variation of the geometric throat area, outlet mass flow rate and nozzle thrust with the position of the pintle is studied. It is found that the theoretical thrust is quite different from the numerical calculation results, so the thrust model is optimized. Firstly, the calculation method of aerodynamic equivalent throat area is established, and the variation of aerodynamic equivalent throat area with the position of the pintle and working condition is studied. The calculation model of equivalent throat area is optimized, which can better fit the change of aerodynamic equivalent throat area with the position of pintle. Based on this, the thrust model of the nozzle in the over-expansion state is revised, and the optimized thrust model is consistent with the simulation results. Finally, the nozzle thrust under different positions of the pintle and inlet pressures is obtained through cold air test, which verified the accuracy of the thrust model.