在环柱型增益发生器实验系统燃烧室的设计中，将主稀释剂He从两个不同的区域注入燃烧室，其中一部分与D2预混以后通过D2喷注孔注入，另一部分通过主喷管叶片后端的后向喷注孔注入。讨论了不同区域的主稀释剂流量的变化对激光器特性的影响。实验结果表明：后He流量改变时，激光器的功率变化及点火稳定性等明显优于前He流量改变的情况。若要增加主稀释剂比例，应优先考虑调整后He。

In experimental facility of cylindrical gain generator assembly for HF chemical laser, primary diluent He is injected into combustor from two different regions. Some of He is injected by D2 jet orifices after being premixed with D2. The other of He is injected by backward He jet orifices at back end of primary nozzle blade. The effect of changing mass flow rate of onward He or backward He on laser’s characteristics is studied by a couple of lasing experiments. The experimental results show that, as compared with changing mass flow rate of onward He, changing mass flow rate of backward He can acquire much higher output power and better ignition stability. When primary diluent ratio is required to be increased, changing mass flow rate of backward He should be given priority．