Aircraft Propulsion, 2nd Edition

CHAPTER 12 Chemical Rocket and Hypersonic Propulsion

12.1 Introduction

Source: Courtesy of NASA (Constellation Program)

A chemical rocket is a self-contained jet engine that carries both the fuel and oxidizer that are needed for combustion. The fuel and oxidizer are jointly called the propellant. Since the rocket carries its own oxidizer, it does not need an air inlet to provide oxygen for combustion, as in a gas turbine engine. It is this independence of rocket operation from atmospheric air that makes it a good candidate for space propulsion. The relative simplicity and manufacturing cost of a rocket engine as compared with an airbreathing jet engine have made rockets the propulsor of choice for low-cost weapons and aerospace vehicle boost applications. For example, the Space Shuttle uses two solid rocket boosters (known as SRBs) to help achieve liftoff and vehicle acceleration to orbit. The Space Shuttle also uses a liquid propellant rocket engine as its main engine, dubbed SSME or Space Shuttle Main Engine. Depending on the form of propellant that is used in combustion, a chemical rocket may be called a liquid propellant, a solid propellant, a gaseous propellant rocket or, if the fuel is in solid form and the oxidizer is in liquid (or gaseous) form, the rocket is called a hybrid. For a liquid propellant rocket, the fuel and oxidizer are stored in separate tanks in liquid ...