Right then - you won't let it lie will you! I've had a little think and....
Turbocharger - A turbocharger, often called a turbo, is a small radial fan pump driven by the energy of the exhaust flow of an engine. A turbocharger consists of a turbine and a compressor on a shared axle. The turbine inlet receives exhaust gases from the engine causing the turbine wheel to rotate. This rotation drives the compressor, compressing ambient air and delivering it to the air intake manifold of the engine at higher pressure, resulting in a greater mass of air entering each cylinder. In some instances, compressed air is routed through an intercooler before introduction to the intake manifold.
The objective of a turbocharger is the same as a supercharger; to improve upon the size-to-output efficiency of an engine by solving one of its cardinal limitations. A naturally aspirated automobile engine uses only the downward stroke of a piston to create an area of low pressure in order to draw air into the cylinder through the intake valves. Because the pressure in the atmosphere is no more than 1 bar (approximately 14.7 psi), there ultimately will be a limit to the pressure difference across the intake valves and thus the amount of airflow entering the combustion chamber. This ability to fill the cylinder with air is its volumetric efficiency. Because the turbocharger increases the pressure at the point where air is entering the cylinder, a greater mass of air (oxygen) will be forced in as the inlet manifold pressure increases. The additional oxygen makes it possible to add more fuel, increasing the power and torque output of the engine.
Because the pressure in the cylinder must not go too high to avoid detonation and physical damage, the intake pressure must be controlled by controlling the rotational speed of the turbocharger. The control function is performed by a wastegate, which routes some of the exhaust flow away from the exhaust turbine. This controls shaft speed and regulates air pressure in the intake manifold.
The application of a compressor to increase pressure at the point of cylinder air intake is often referred to as forced induction. Centrifugal superchargers compress air in the same fashion as a turbocharger. However, the energy to spin the supercharger is taken from the rotating output energy of the engine's crankshaft as opposed to normally exhausted gas from the engine. Superchargers use output energy from an engine to achieve a net gain, which must be provided from some of the engine's total output. Turbochargers, on the other hand, convert some of the piston engine's exhaust into useful work. This energy would otherwise be wasted out the exhaust. This means that a turbocharger is a more efficient use of the heat energy obtained from the fuel than a supercharger.
Explosion - An explosion is a sudden increase in volume and release of energy in an extreme manner, usually with the generation of high temperatures and the release of gases. An explosion creates a shock wave.
Combustion - Combustion or burning is a complex sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat or both heat and light in the form of either a glow or flames.
Direct combustion by atmospheric oxygen is a reaction mediated by radical intermediates. The conditions for radical production are naturally produced by thermal runaway, where the heat generated by combustion is necessary to maintain the high temperature necessary for radical production.
In a complete combustion reaction, a compound reacts with an oxidizing element, such as oxygen or fluorine, and the products are compounds of each element in the fuel with the oxidizing element. For example:
CH4 + 2O2 → CO2 + 2H2O
CH2S + 6F2 → CF4 + 2HF + SF6
A simpler example can be seen in the combustion of hydrogen and oxygen, which is a commonly used reaction in rocket engines:
2H2 + O2 → 2H2O(g) + heat
The result is water vapor.
In the large majority of the real world uses of combustion, the oxygen (O2) oxidant is obtained from the ambient air and the resultant flue gas from the combustion will contain nitrogen:
CH4 + 2O2 + 7.52N2 → CO2 + 2H2O + 7.52N2 + heat
As can be seen, when air is the source of the oxygen, nitrogen is by far the largest part of the resultant flue gas.
In reality, combustion processes are never perfect or complete. In flue gases from combustion of carbon (as in coal combustion) or carbon compounds (as in combustion of hydrocarbons, wood etc.) both unburned carbon (as soot) and carbon compounds (CO and others) will be present. Also, when air is the oxidant, some nitrogen can be oxidized to various nitrogen oxides (NOx).
And I didn't look any of that up
Now what have you got to say
let's move on......
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