In
mechanics
Mechanics (from Ancient Greek: μηχανική, ''mēkhanikḗ'', "of machines") is the area of mathematics and physics concerned with the relationships between force, matter, and motion among physical objects. Forces applied to object ...
, a diaphragm is a sheet of a semi-flexible material anchored at its periphery and most often round in shape. It serves either as a barrier between two chambers, moving slightly up into one chamber or down into the other depending on differences in
pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and e ...
, or as a device that vibrates when certain frequencies are applied to it.
A
diaphragm pump uses a diaphragm to
pump a
fluid. A typical design is to have air on one side constantly vary in pressure, with fluid on the other side. The increase and decrease in volume caused by the action of the diaphragm alternately forces fluid out the chamber and draws more fluid in from its source. The action of the diaphragm is very similar to the action of a
plunger
A plunger, force cup, plumber's friend or plumber's helper is a tool used to clear blockages in drains and pipes. It consists of a rubber suction cup attached to a stick (''shaft'') usually made of wood or plastic. A different bellows-like des ...
with the exception that a diaphragm responds to changes in pressure rather than the mechanical force of the shaft.
A diaphragm
pressure tank
A pressure tank or pressurizer is used in a piping system to maintain a desired pressure. Applications include buffering water pressure in homes.
A simple well water control system
Referring to the figure on the left, a submersible water ...
is a tank which has pressurant sealed inside on one side of the diaphragm. It is favored in certain applications due to its high durability and reliability. This comes with a downside, as the vessel needs to be replaced in the case of a rupture of the diaphragm.
Diaphragm tanks are used to store
hypergolic propellant aboard space probes and various other spacecraft.
Pressure regulators use diaphragms as part of their design. Most uses of compressed gasses, for example, in
gas welding
Principle of burn cutting
Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding, or gas welding in the United States) and oxy-fuel cutting are processes that use fuel gases (or liquid fuels such as gasoline or petrol, diesel, ...
and
scuba diving
Scuba diving is a mode of underwater diving whereby divers use breathing equipment that is completely independent of a surface air supply. The name "scuba", an acronym for " Self-Contained Underwater Breathing Apparatus", was coined by Chr ...
rely on regulators to deliver their gas output at appropriate pressures. Automotive
fuel systems frequently require fuel-pressure regulators; this is true of many
fuel injection systems as well as in vehicles fueled with
liquefied petroleum gas (
autogas) and
compressed natural gas
Compressed natural gas (CNG) is a fuel gas mainly composed of methane (CH4), compressed to less than 1% of the volume it occupies at standard atmospheric pressure. It is stored and distributed in hard containers at a pressure of , usually in cy ...
.
See also
*
Gas engine
*
Hybrid vehicle
References
Mechanics.
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