Rocket Engines

FUEL Fuel is something that can be burnt to produce energy in the form of heat or power . Those substances which are classified as fuel must necessarily contain one or several of the combustible elements : carbon, hydrogen, sulphur, etc. In the process of combustion, the chemical energy of fuel is converted into heat energy. To utilize the energy of fuel in most usable form, it is required to transform the fuel from its one state to another, i.e. from solid to liquid or gaseous state, liquid to gaseous state, or from its chemical energy to some other form of energy via single or many stages. In this way, the energy of fuels can be utilized more effectively and efficiently for various purposes.

Starting with some basics about space transportation systems such as the thrust equation and some mission requirements, the paper explains the underlying physical and technical challenges every rocket engine design engineer faces at the beginning of a project. A brief overview about the main subsystems of a liquid rocket engine such as turbopumps and gas generators is followed by a more detailed description of the thrust chamber assembly, the injector head, the ignition system and the combustion chamber liner which includes the first part of the nozzle and finally the nozzle extension. The technological challenges of these components are presented which result from the severe operating conditions and their current design principles and production technologies.

The principle of rocket propulsion follows Newton's famous third law of motion, which states that to every action there is an equal and opposite reaction. A rocket engine travels by expelling mass in one direction while at the same time using the reaction to move in the other direction. This Paper describes role, function and composition of Turbopump that are used to drive whole rocket. A rocket turbine engine is a combination of two types of propulsion engines: a liquid fuel rocket and a turbine jet engine. A rocket engine is a type of jet engine that uses only stored rocket propellant mass for forming its high speed propulsive jet. Rocket engines are reaction engines, most rocket engines are internal combustion engines, although non-combusting forms (such as cold gas thrusters) also exist. Compared to other types of jet engines, rocket engines have the highest thrust, are by far the lightest, but are the least propellant efficient (have the lowest specific impulse). Rocket engines become more efficient at high velocities (due to greater propulsive efficiency and Oberth effect-it is a maneuver in which a rocket falls into a gravitational well, and then accelerates when its fall reaches maximum speed).

Resonance, 2011

The most common answer to the above question is — hot jet of gas comes out of the nozzle of the rocket engine at high speeds and as a reaction the rocket moves (is propelled) in the opposite direction [1]. But is this answer right? Let us explore what goes on inside a rocket engine and arrive at the right answer.

International Journal of Aerospace Engineering, 2012

A hybrid rocket is a rocket engine which uses propellants in two different states of matter-one is in solid and the other either gas or liquid. A hybrid rocket exhibit advantages over both liquid rockets and solid rockets especially in terms of simplicity, stop-start-restart capabilities, safety and cost. This paper deals the design and development of a hybrid rocket having paraffin wax as solid fuel and liquid oxygen as oxidizer. Due to variation of pressure in combustion chamber there is significantly change in mass flow rate, burning rate and uneven regression along the length of the grain.

Propulsion is generally a mature science, but one technology has recently generated a lot of research and development by offering safer and cheaper means of propulsion. It is called the hybrid rocket technology, which has transformed the space industry during the last two decades. Unfortunately, this technology has not been given its due share in academia and industry outside the Western hemisphere.

Nature, 1960

Je t propulsion, sim ilar to all means of propulsion, is based on Newton's Second and Third laws of motion. Mach number is the ratio of the flight speed of the air plane or missile to the sonic velocity

2020

Chemical rocket engines play an important role in space travel as they produce high thrust, required for initial liftoff of the rocket. Deep space exploration mission is very expensive, as most of the engines in use are chemical rocket engines and they operate with low efficiency. Even if electric propulsion systems are used, they cannot replace the solid or liquid propellant rocket engines, as only they are capable of generating high thrust. The thrust is essentially generated by combustion process of fuel and oxidizer. But the thrust is fundamentally a function of mass flow rate, pressure and velocity of the exhaust gas and the temperature gained due to the combustion does not contribute to the generation of thrust. By the conversion of a property, such as exhaust gas temperature, which cannot contribute to increase of thrust into a useful property such as the exhaust gas pressure, the efficiency of thrust generated by the rocket engine at the nozzle chamber exit can be improved. ...

2016

Comparative study of an additional oxidizer charge effect on selected operational characteristics of a solid-fuel rocket engine