Rocket Engine with Continuous Detonation Combustion of the Natural Gas–Oxygen Propellant System

In a demonstrator of a detonation rocket engine (DRE) using the natural gas–oxygen propellant system, a high (270 s) specific impulse at sea level at a low (32 atm) mean combustor pressure was experimentally obtained for the first time. Comparison of these characteristics with the respective ones (263 s and 61 atm) of the well-known Russian RD 170-A liquid-propellant rocket engine using deflagration combustion of the kerosene–oxygen propellant system showed that the specific impulse at sea level in the DRE is close to that in the deflagration-combustion engine but is produced at half as high a mean combustor pressure. This indicates that the energy efficiency of detonation combustion exceeds that of deflagration combustion, and that there is room to improve the weight–size characteristics of the turbopump unit in the DRE.