Thermal Propulsion

Abstract

The thrust from thermal propulsion engines, such as jet engines, results from the exhaust of propellant gases, which is achieved by the rapid expansion of the heated gas. The heat usually comes from the combustion of chemical propellants—which we will assume in the following without loss of generality—or from the supply of external heat, or from both. A chemical propellant, therefore, serves two different purposes at the same time: it is a provider of mass for the required mass flow rate and a provider of energy to accelerate itself to ejection velocity.