word looked up : home / archive

 Internal-combustion engine : Internal combustion engine 

An internal-combustion engine is any engine that operates by burning its fuel inside the engine. In contrast an external combustion engine burns its fuel outside the engine, for example a steam engine. In general, the term 'internal combustion engine' is used only to refer to engines in which fuel is burned intermittently, thus excluding jet engines and gas turbines which burn fuel continuously.


The de Havilland Gypsy Queen engine, powering Dove and Heron propeller aircraft.
Larger version

The most common internal combustion engines are the gasoline powered engine and the diesel engine. Others include those fueled by hydrogen, methane, propane, etc. Engines typically can only run on one type of fuel and require adaptations to adjust the air/fuel ratio or mix to use other fuels.

In a gasoline engine, a mixture of gasoline and air is sprayed into a cylinder. This is compressed by a piston and at optimal point in the compression stroke, a spark plug creates an electrical spark that ignites the fuel. The combustion of the fuel results in the generation of heat, and the hot gases that are in the cylinder are then at a higher pressure than the fuel-air mixture and so drive the piston back down. These combustion gases are vented and the fuel-air mixture reintroduced to run a second stroke. The outward linear motion of the piston is ordinarily harnessed by a crankshaft to produce circular motion. Valves control the intake of air-fuel mixture and allow exhaust gases to exit at the appropriate times.

A critically important portion of any internal-combustion engine is its ignition system, which controls the timing of the burning of the fuel mixture. If this burn begins either too early or too late the engine performance will be reduced, sometimes seriously, and in extreme cases can even damage the engine.

Some types of ignition systems that have been or are used in internal-combustion engines are:

Early mechanical ignition system. Already obsolete before 1911.
Early ignition system. Was still common in 1911.
The precise control these provide soon made all earlier devices obsolete. All modern internal-combustion engines (except the diesel) use them.
Only used in diesel engines. Actual timing controlled by fuel injection system.

See also: two stroke cycle, four stroke cycle, diesel cycle, Otto cycle, rotary engine (Wankel), Miller cycle, stratified charge engine and Gas Laws, Samuel Morey

Phillip Morrison said, "Suddenly, not only was heat.html">heat of the sun on our faces....Then, only minutes later, the real sun So we saw two sunrises." After the explosion.html">explosion atomic bomb was used as a weapon against Japan, people in New Mexico and was felt by many at least 160 miles away. Army officials simply Alamogordo bombing.html">Bombing Range. The explosion did not make much of a crater. Most eyewitnesses The heat of the blast did melt the desert sand and turn it into a in the area. At one time Trinitite completely covered the depression of the Trinitite was taken away by the Nuclear Energy Commission. To the west of the monument is a low structure which is protecting an openings in the roof.html">roof. It's the Schmidt house.html">house.html">house.html">house.html">house The house was built in 1913 by Franz Schmidt, a German immigrant, and McDonalds. There is a display about the Schmidt family in the house built of adobe which was plastered and painted. An ice house is stored rain water running off the roof. At one time the north.html">north tank northwest of the house. There is a large, divided water storage tank and a Chicago Aeromotor the north tank as a swimming pool during the long hot summer of 1945. was part garage. Further to the east are corrals and holding pens. prevent further deterioration. The ranch was abandoned in 1942 when the Alamogordo Bombing and bombing crews. The house stood empty until the Manhattan.

 On wordlookup.net  

All is still licensed under the GNU FDL.
It uses material from the wikipedia.



logo

navig stuff

home
archive