1. Supersonic flows with combustion: one-dimensional calculation

The calculation of a propulsion system is largely based on one-dimensional equations. For this type of calculation, the one-dimensional balance equations given here are supplemented by phenomenological and empirical relationships designed to reproduce the various pressure losses induced by the system's geometry and injection devices. These calculations enable us to determine the ranges of input parameters and the overall geometry of the system required to achieve positive thrust, and to calculate it effectively. Despite the drastic assumptions involved in such a calculation, it is a necessary prerequisite for the development of a propulsion system: it enables us to decide whether the process and the geometry in which it is to be developed can be made operational. If, following such a calculation, the thrust calculated for the chosen system proves insufficient, there is generally no need...