Rocket propulsion, principles

The design of propellants for solid fuel rockets differs considerably from that for ordnance, because of the lower operating pressures, usually below 15 MPa. To understand the principles involved it is first necessary to give a brief account of rocket propulsion. In this account considerations will be restricted to motors based on solid propellants. Motors based on liquid fuels, such as petroleum fractions and liquid oxygen, depend on combustion processes of non-explosive type. 

Chapter 6. Launch Systems and Launch Sites. Section 1 Principles of Rocket Propulsion. Army Space Reference Text, US Army Space Institute, Fort Leavenworth, KS, http //www.fas.org/spp/military/docops/army/ref text/chap6im.htm... 

Turner, M.J.L. (2000) Rocket and Spacecraft Propulsions Principle, Practice and New Developments, Praxis Publishing Ltd, UK, pp. 97-98. 

Solid-propellant rocket engines are attractive because of their simple propulsion principle, which avoids alimentation systems needed to produce combustion. Both oxidizer and fuel elements are present in a chemically stable material (the propellant), which is shaped to fit the motor itself. This feature, in particular, represents an obvious advantage for military applications such as nuclear ballistic missiles, which require a long-term storage capability and high service safety (3). 

We now turn to a slightly more technical discussion of the nuclear rocket. It is well known that the basic equations of rocket propulsion are derivable from the principle of momentum conservation and Newton s laws of motion. Thus ejection of a mass m of... 

Spyra WPW, Winkehnann K (2004) The conversion of liquid rocket fuels. Kluwer, Netherlands Sutton GP, Biblatz O (2001) Rocket propulsion elements, 7th edn. Wiley, New York Turner MIL (2005) Rocket and spacecraft propulsion principles, practice and new developments. Springer, Berlin... 

Engineering is the application of scientific and mathematical principles for practical purposes. Engineering is subdivided into many disciplines aU create new products and make existing products or systems work more efficiently, faster, safer, or at less cost. The products of engineering are ubiquitous and range from the familiar, such as microwave ovens and sound systems in movie theaters, to the complex, such as rocket propulsion systems and genetic engineering. 

The fundamental principle of rocket propulsion is Sir Isaac Newton s third law of motion For every action, there is an equal and opposite reaction. The mass of fuel ejected rearward from a rocket results in the rocket being propelled forward. More precisely, the mass of fuel multiplied by the exhaust velocity equals the force pushing the rocket forward multiplied by the bum time. It follows then that the greatest amount of mass possible must be ejected each second at the highest possible speed to provide maximum acceleration to a rocket. The maximum exhaust speed for a chemical rocket is about 3 to 5 kilometers per second, but the exhaust speed for an ion engine can be 30 to 50 kilometers per second or greater. 

Rockets use the principle of jet propulsion. This is the application of Newton s famous Third Law of Motion that action and reaction are equal and opposite . If... 

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