喷管中气固两相流动的无颗粒区

The gas-particle two-phase flow is encountered in various industrial applications, such as the solid-propellant rocket motors. However, the condition for the emergence of the particle-free zone is still ambiguous, and the influence of the particle-free zone on the two-phase interaction and thrust is still unclear. In this work, we built an Eulerian-Lagrangian method for the simulation of the gas-particle flow in a JPL 45°∼15° nozzle. Various parameters, such as the range of the particle-free zone, the thrust, the specific impulse, the two-phase loss and the nozzle efficiency, were examined. We found that the particle-free zone does exist only for 1 μm particles. Moreover, the thrust does not change monotonously with particle size, which has not been noticed before. On the contrary, the two-phase loss, the specific impulse and the nozzle efficiency change logarithmically with particle size.