图表示不同二次氮气压力下焰流速度与轴向距离的关系。如前所述，二次氮气的注入导致喷枪内部焰流的温度迅速下降，引起拉瓦尔喷嘴内部及之后焰流速度的降低，随着二次氮气压力的不断增加，焰流速度的降低程度也更明显。从气体的自由射流阶段可以看出，相比于不注入二次氮气，虽然焰流速度有所下降，但焰流的高速区范围更大，焰流具有更好的速度保持性，这对于粒子的加速是非常有利的。

The graph represents the flame flow velocity versus axial distance at different secondary nitrogen pressures. As mentioned earlier, the injection of secondary nitrogen causes a rapid decrease in the temperature of the flame stream inside the gun, causing a decrease in the flame stream velocity inside and after the Laval nozzle, and a more pronounced decrease in the flame stream velocity as the secondary nitrogen pressure continues to increase. It can be seen from the free jet phase of the gas that, compared to no secondary nitrogen injection, although the flame flow velocity decreases, the flame flow has a larger range of high velocity zones and the flame flow has better velocity retention, which is very beneficial for particle acceleration.