Most of hydrocarbon fuels often have larger methane numbers than hydrogen. It is more difficult to detonate the mixture of hydrocarbon fuels and air at room temperatures in non-premixed engines since the mixing is slower than hydrogen-air mixing and the mixing is slower at lower temperatures. Ethylene–air rotating detonation operations have been successful, but methane-ethylene-air mixture at room temperatures is more difficult to detonate for rotating detonation engines since methane is more chemically stable. The hollow combustor channel here had an outer diameter of 220 mm and a length of 163 mm. Methane-ethylene mixture was injected axially into the combustor from cylindrical orifices in a diameter of 0.8 mm, and air was injected radially through a convergent-divergent circular channel with a throat width of 0.8 mm. Non-premixed rotating detonation waves were obtained for methane-ethylene-air mixture at total temperatures of 280–285 K in the present study. Both high-speed images and pressure traces show that three-wave mode has a higher detonation speed than five-wave mode. The rotating detonation speed is increased with the increased detonation height.

大多数碳氢化合物燃料通常具有比氢更大的甲烷值。在室温下在非预混发动机中引爆碳氢化合物燃料和空气的混合物更加困难，因为混合比氢-空气混合慢，并且在较低温度下混合更慢。乙烯-空气旋转爆震操作已经成功，但室温下的甲烷-乙烯-空气混合物对于旋转爆震发动机来说更难引爆，因为甲烷的化学性质更稳定。这里的空心燃烧器通道的外径为 220 毫米，长度为 163 毫米。甲烷-乙烯混合物从直径为 0.8 毫米的圆柱形孔口轴向注入燃烧器，空气通过喉部宽度为 0.8 毫米的会聚-发散圆形通道径向注入。在本研究中，甲烷-乙烯-空气混合物在 280-285 K 的总温度下获得了非预混旋转爆震波。高速图像和压力轨迹均表明三波模式比五波模式具有更高的爆速。旋转爆轰速度随着爆轰高度的增加而增加。