A combustion chamber is the part of an engine Engines come in many types, a common type is a heat engine such as an internal combustion engine which typically burns a fuel with air and uses the hot gases for generating power. External combustion engines such as steam engines use heat to generate motion via a separate working fluid in which fuel Fuel is any material that can be used to generate energy to produce mechanical work in a controlled manner. The processes used to convert fuel into energy include chemical reactions, such as combustion, and nuclear reactions, such as nuclear fission or nuclear fusion. Fuels are also used in the cells of organisms in a process known as metabolism is burned.
Contents |
Internal combustion engine
Diagram of jet engine showing the combustion chamber.The hot gases Gas is one of four classical states of matter. Near absolute zero, a substance exists as a solid. As heat is added to this substance it melts into a liquid at its melting point , boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons are so energized that they leave their parent atoms produced by the combustion Combustion or burning is the sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat and conversion of chemical species. The release of heat can result in the production of light in the form of either glowing or a flame. Fuels of interest often include organic compounds in the gas, liquid or occupy a far greater volume than the original fuel, thus creating an increase in pressure Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure within the limited volume of the chamber. This pressure can be used to do work, for example, to move a piston A piston is a component of reciprocating engines, pumps and gas compressors. It is located in a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from expanding gas in the cylinder to the crankshaft via a piston rod and/or connecting rod. In a pump, the function is reversed and force is transferred from on a crankshaft The crankshaft, sometimes casually abbreviated to crank, is the part of an engine which translates reciprocating linear piston motion into rotation. To convert the reciprocating motion into rotation, the crankshaft has "crank throws" or "crankpins", additional bearing surfaces whose axis is offset from that of the crank, to or a turbine disc A turbine is a rotary engine that extracts energy from a fluid flow and converts it into useful work in a gas turbine A gas turbine, also called a combustion turbine, is a rotary engine that extracts energy from a flow of combustion gas. It has an upstream compressor coupled to a downstream turbine, and a combustion chamber in-between. Gas turbine may also refer to just the turbine component. The energy can also be used to produce thrust Thrust is a reaction force described quantitatively by Newton's second and third laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system when directed out of a nozzle A nozzle is a mechanical device designed to control the direction or characteristics of a fluid flow as it exits an enclosed chamber or pipe via an orifice as in a rocket engine A rocket engine, or simply "rocket," is a jet engine that uses only propellant mass for forming its high speed propulsive jet. Rocket engines are reaction engines and obtain thrust in accordance with Newton's third law. Since they need no external material to form their jet, rocket engines can be used for spacecraft propulsion as well as.
Petrol or gasoline engine
A reciprocating engine A reciprocating engine, also often known as a piston engine, is a heat engine that uses one or more reciprocating pistons to convert pressure into a rotating motion. This article describes the common features of all types. The main types are: the internal combustion engine, used extensively in motor vehicles; the steam engine, the mainstay of the is often designed so that the moving pistons A piston is a component of reciprocating engines, pumps and gas compressors. It is located in a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from expanding gas in the cylinder to the crankshaft via a piston rod and/or connecting rod. In a pump, the function is reversed and force is transferred from are flush with the top of the cylinder block The cylinder block or engine block is a machined casting containing cylindrically bored holes for the pistons of a multi-cylinder reciprocating internal combustion engine, or for a similarly constructed device such as a pump. It is a complex part at the heart of an engine, with adaptions to attach the cylinder head, crankcase, engine mounts, drive at top dead centre In a reciprocating engine, the dead centre is the position of a piston in which it is farthest from, or nearest to, the crankshaft. The former is known as top dead centre while the latter is known as bottom dead centre (BDC). The combustion chamber is recessed in the cylinder head In an internal combustion engine, the cylinder head sits above the cylinders on top of the cylinder block. It consists of a platform containing part of the combustion chamber (usually, though not always), and the location of the poppet valves and spark plugs. In a flathead engine, the mechanical parts of the valve train are all contained within and commonly contains a single intake valve and a single exhaust valve. Some engines use a dished piston and in this case the combustion chamber can be considered as partly within the cylinder. Various shapes of combustion chamber have been used, such as L-head (or flathead A flathead engine or sidevalve engine is an internal combustion engine with valves placed in the engine block beside the piston, instead of in the cylinder head, as in an overhead valve engine. The design was common on early engine designs, but has since fallen from use) for side-valve engines;"bathtub", "hemispherical" and "wedge" for overhead valve engines; and "pent-roof" for engines having 3, 4 or 5 valves per cylinder. The shape of the chamber has a marked effect on power output, efficiency and harmful emissions; the designer's objectives are to burn all of the mixture as completely as possible while avoiding excessive temperatures (which create NOx At ambient temperatures, the oxygen and nitrogen gases in air will not react with each other. In an internal combustion engine, combustion of a mixture of air and fuel produces combustion temperatures high enough to drive endothermic reactions between atmospheric nitrogen and oxygen in the flame, yielding various oxides of nitrogen. In areas of). This is best achieved with a compact rather than elongated chamber. The intake valve/port Cylinder head porting refers to the process of modifying the intake and exhaust ports of an internal combustion engine to improve the quality and quantity of the air flow. Cylinder heads, as manufactured, are usually suboptimal due to design and manufacturing constraints. Porting the heads provides the finely detailed attention required to bring is usually placed to give the mixture a pronounced "swirl" (the term is preferred to turbulence In fluid dynamics, turbulence or turbulent flow is a fluid regime characterized by chaotic, stochastic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and velocity in space and time. Nobel Laureate Richard Feynman describes turbulence as "the most important unsolved problem of which implies movement without overall pattern) above the rising piston, improving mixing and combustion. The shape of the piston top also affects the amount of swirl. Note that swirl rotates about a horizontal axis, not (symmetrically) about a vertical axis. Finally, the spark plug must be situated in a position from which the flame front can reach all parts of the chamber at the desired point, usually around 15 degrees after top dead centre In a reciprocating engine, the dead centre is the position of a piston in which it is farthest from, or nearest to, the crankshaft. The former is known as top dead centre while the latter is known as bottom dead centre (BDC). It is strongly desirable to avoid narrow crevices where stagnant "end gas" can become trapped, as this tends to detonate Knocking in spark-ignition internal combustion engines occurs when combustion of the air/fuel mixture in the cylinder starts off correctly in response to ignition by the spark plug, but one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front. The fuel-air charge is meant to be ignited by the spark plug violently after the main charge, adding little useful work and potentially damaging the engine. Also, the residual gases displace room for fresh air/fuel mixture and will thus reduce the power potential of each firing stroke.
Diesel engine
- Direct injection, where the combustion chamber consists of a dished piston
- Indirect injection In an internal combustion engine, the term indirect injection refers to a fuel injection where fuel is not directly injected into the combustion chamber. Gasoline engines are usually equipped with indirect injection systems, wherein a fuel injector delivers the fuel at some point before the intake valve, where the combustion chamber is in the cylinder head
Direct injection engines usually give better fuel economy but indirect injection engines can use a lower grade of fuel.
Harry Ricardo Sir Harry Ricardo was one of the foremost engine designers and researchers in the early years of the development of the internal combustion engine was prominent in developing combustion chambers for diesel engines, the best known being the Ricardo Comet.
Steam engine
The term combustion chamber is also used to refer to an additional space between the firebox and boiler A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications in a steam locomotive A steam locomotive is a locomotive powered by a steam engine. The term usually refers to its use on railways, but can also refer to a "road locomotive" such as a traction engine or steamroller. This space is used to allow further combustion of the fuel, providing greater heat to the boiler.
Large steam locomotives usually have a combustion chamber in the boiler to allow the use of shorter firetubes A fire-tube boiler is a type of boiler in which hot gases from a fire pass through one or more tubes running through a sealed container of water. The heat energy from the gases passes through the sides of the tubes by thermal conduction, heating the water and ultimately creating steam. This is because:
- Long firetubes have a theoretical advantage in providing a large heating surface but, beyond a certain length, this is subject to diminishing returns In economics, diminishing returns refers to how the marginal production of a factor of production starts to progressively decrease as the factor is increased, in contrast to the increase that would otherwise be normally expected. According to this relationship, in a production system with fixed and variable inputs (say factory size and labor),.
- Very long firetubes are prone to sagging in the middle.
See also
| Wikimedia Commons has media related to: Combustion chamber |
- cylinder head In an internal combustion engine, the cylinder head sits above the cylinders on top of the cylinder block. It consists of a platform containing part of the combustion chamber (usually, though not always), and the location of the poppet valves and spark plugs. In a flathead engine, the mechanical parts of the valve train are all contained within
- engine displacement Engine displacement is the volume swept by all the pistons inside the cylinders of an internal combustion engine in a single movement from top dead centre to bottom dead centre (BDC). It is commonly specified in cubic centimeters (cc), litres (l), or (mainly in North America) cubic inches (CID). Motive power output of a combustion engine is
- combustor A combustor is a component or area of a gas turbine, ramjet, or scramjet engine where combustion takes place. It is also known as a burner or flame can. In a gas turbine engine, the main combustor or combustion chamber is fed high pressure air by the compression system and feeds the hot, high pressure exhaust into the turbine components of the
- Variable compression ratio
Categories: Engine technology | Locomotive parts | Gas turbine technology
|
Maple Ridge News
Pipes carrying water snake through the combustion chamber and the resulting steam turns turbines to generate close to 18 megawatts of electricity. ...
and more »
Ian
Mon, 02 Aug 2010 15:02:38 GM
Including special tapered Valve Guides 2) Flat-top Pistons (same compression ratio) allowing unique . Combustion Chamber. 3) 40mm Exhaust Header 4) Special Off-Road Only Silentium Silencers 5) Different Spec Webber Carb ...
