Effects of injection schemes on the performance of powdered magnesium-liquid CO₂ rocket engine

The effects of self-impinging injection and unlike-impinging injection on the performance of powdered magnesium-liquid carbon dioxide rocket engine have been investigated via numerical simulation and experimentation. The results indicate that the unlike-impinging injection achieves a combustion efficiency of 88.7%, which is 23% higher than that of self-impinging injection. Moreover, significant deposition of unburned magnesium particles is observed at the head of the combustor when using self-impinging injection, whereas unlikeimpinging injection exhibits much less deposition. Self-impinging injection leads to an uneven temperature field distribution at the head of the combustion chamber, while high temperature areas under the unlike-impinging injection scheme are relatively concentrated. The mutual collision between carbon dioxide droplets also reduces the degree of mixing between carbon dioxide droplets and magnesium particles under self-impinging injection which is less likely to occur in the unlike-impinging injection scheme.