Flows in the rocket engine nozzles have been numerically analyzed to assess the performance of thrust vector control system of fluidic type by the direct simulation Monte Carlo method. Secondary jet is injected through a small port at one side of two-dimensional dual throat nozzle wall. If the cross-sectional areas of both throats are identical (nozzle A), and the injection port is near the first throat, the main flow separation caused by the secondary jet is observed, and a steady-state thrust deflection of about 18° is obtained when the flow rate of the secondary jet is 5% of the total fluid. However, the deflection also occurs randomly when the secondary jet is stopped. To avoid it, the second throat is widened to 1.50 times the cross-sectional area of the first throat (nozzle B), and it is observed that the thrust deflection is nearly zero for all cases without secondary jet injection. However, the thrust deflection is only about 5° when the secondary jet is injected near the first throat of nozzle B. When the injection port is placed further downstream of the first throat in nozzle B, thrust deflections between 14 and 15° are obtained.

通过直接模拟蒙特卡罗方法对火箭发动机喷嘴中的流动进行了数值分析，以评估流体型推力矢量控制系统的性能。二次射流通过二维双喉喷嘴壁一侧的小孔喷射。如果两个喉道的横截面积相同（喷嘴A），并且喷射口靠近第一个喉道，则观察到二次射流引起的主流分离，稳态推力偏转约为18°当二次射流的流量为总流体的 5% 时获得。然而，当二次射流停止时，偏转也会随机发生。为避免这种情况，将第二个喉部加宽到第一个喉部（喷嘴 B）截面积的 1.50 倍，并且可以观察到，对于所有没有二次喷射喷射的情况，推力偏转几乎为零。然而，当二次射流在喷嘴 B 的第一个喉道附近喷射时，推力偏转只有大约 5°。当喷射口放置在喷嘴 B 中第一个喉道的更下游时，推力偏转在 14 到 15° 之间。