以2 MPa二次氮气压力为例对焰流压力进行分析，如图所示。燃烧室内部压力趋近于二次注氮压力，氮气的掺混会导致激波现象不明显，由于激波的压力差小于图例的单位压力差，导致在云图中不易发现自由射流区的激波，但从后续压力曲线图中的锯齿状结构可以看出，喷管出口处有激波的存在。

The 2 MPa secondary nitrogen pressure is used as an example to analyze the flame flow pressure, as shown in the figure. The pressure inside the combustion chamber tends to be close to the secondary nitrogen injection pressure, and the blending of nitrogen will lead to a less obvious surge phenomenon. Since the pressure difference of the surge is smaller than the unit pressure difference of the legend, it is not easy to find the surge in the free jet area in the cloud diagram, but the presence of the surge at the nozzle exit can be seen from the sawtooth structure in the subsequent pressure diagram.