Various Definitions Related to the Mechanical Engineering Part 3

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Turbocharging:
Turbocharging is similar to the supercharging. But in that case turbocharger is installed in exhaust system whereas supercharger is installed in intake system. Turbocharger is driven by force of exhaust gas. Generally, turbocharger is used for 2-stroke engine by utilizing exhaust energy of the engine, it recovers energy otherwise which would go waste.

Governor:
Its function id to regulate mean speed of engine when there are variation in the load. If load increases on the engine, then engine’s speed must decrease. In that case supply of working fluid have to increase. In the other way, if load decrease on the engine, then engine’ speed must increase. In that case supply of working fluid have to decrease.Governor automatically, controls the supply of working fluid to the engine with varying load condition.

Flywheel:
It is the one of the main parts of the I.C. engine. Its main function id to store energy in the time of working stroke or expansion stroke. And, it releases energy to the crankshaft in the time of suction stroke, compression stroke & exhaust stroke. Because, engine has only one power producing stroke.

Rating of fuel:
S.I. Engine:
Octane number. Octane number indicates ability of fuel to resist knock.

C.I. Engine:
Cetane Number. Cetane number indicates ability of ignition of diesel fuel. That means, how much fast ignites diesel fuel.

Stoichiometric ratio:
It is the chemically correct air-fuel ratio by volume. By which theoretically sufficient oxygen will be gotten to burn all combustible elements in fuel completely.

Heat Transfer:
It is a science which deals with energy transfer between material bodies as a result of temperature difference.There are three way to heat transfer such as-Conduction, Convection and Radiation

Thermal Conductivity:
It is the quantity of heat flows between two parts of solid material by conduction. In this case following consideration will be important fact-

Time—— 1 sec

Area of that solid material——– 1 m²

Thickness of that solid material—— 1 m

Temperature difference between two parts of that material—— 1 k

Heat Exchanger:
It is one type of device which can transfer heat from one fluid to another fluid. Example- Radiator, inter-cooler, preheater, condenser, boiler etc.

Refrigeration:
It is the process of removing heat from a substance. Actually, extraction of heat from a body whose temperature is already below the temperature of its surroundings.

1 tonne of refrigeration:
It is amount of refrigeration effect or cooling effect which is produced by uniform melting of 1 tonne ice in 24 hours from or at 0 degree centigrade or freezing 1 tonne water in 24 hours from or at 0 degree centigrade.

Humidification:
It is the addition of moisture to the air without change dry bulb temperature.

Dehumidification:
It is the removal of moisture from the air without change dry bulb temperature.