A new look at the hot separation of liquid rocket stages

The work aims to find and substantiate a new approach to hot separation of liquid-propellant rocket stages. This separation method is the most energy-efficient when combined with the gas-jet braking and tilting the previous stage. It allows to simplify and reduce the weight of the separation system by tens of kilograms. The research showed a significantly lower effect of the engine combustion products jet on the reflective screen than according to the calculation methods of other authors. An increase in the ratio of fuel components completely excludes the possibility of an explosion. There are no theoretical prerequisites for the ignition and explosion of incompletely oxidized combustion products with the oxidizer vapor of the lower tank under high vacuum conditions. The authors showed that the Knudsen number is bigger than one, and the branched-chain combustion does not happen. Moreover, there are no conditions for fire in case of accidental burn-through of the separated stage upper tank. The practical significance of the work lies in a significant reduction in the weight of the protective screen and increasing the reliability of the hot stage separation system. The proposed method allows safely using in practice the most energy-efficient stage separation scheme.