Total pressure
Encyclopedia
In physics, the term total pressure may indicate two different quantities, both having the dimensions of a pressure:
where ρ is the density of the fluid, g is the local acceleration due to gravity, and z is the height above a datum.
If the variation in height above the datum is zero, or so small it can be ignored, the above equation reduces to the following simplified form:
- In fluid dynamics, total pressure (
) refers to the sum of static pressureStatic pressureIn fluid mechanics the term static pressure has several uses:* In the design and operation of aircraft, static pressure is the air pressure in the aircraft’s static pressure system....
p, dynamic pressure q, and gravitational head, as expressed by Bernoulli's principle:
where ρ is the density of the fluid, g is the local acceleration due to gravity, and z is the height above a datum.
If the variation in height above the datum is zero, or so small it can be ignored, the above equation reduces to the following simplified form:
- In a mixture of ideal gasIdeal gasAn ideal gas is a theoretical gas composed of a set of randomly-moving, non-interacting point particles. The ideal gas concept is useful because it obeys the ideal gas law, a simplified equation of state, and is amenable to analysis under statistical mechanics.At normal conditions such as...
es, total pressure refers to the sum of each gas' partial pressurePartial pressureIn a mixture of ideal gases, each gas has a partial pressure which is the pressure which the gas would have if it alone occupied the volume. The total pressure of a gas mixture is the sum of the partial pressures of each individual gas in the mixture....
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