atmospheric pressure

normal atmospheric pressure is 1.013 x 105 Pa or 101.3 kPa at sea level, the air pressure decreases as you go up in altitude because the pressure is exerted by the column of atmosphere.

The column of fluid, and its pressure at its base, is maximum, at sea level, and it decreases until it becomes zero in the space. it decreases by a factor of 10 every time it rises 16 km (half at 5 500 m). It is thus possible to use pressure to measure the height, which is the basic principle of the altimeter used in aerospace and mountaineering.

A barometer, measures the atmospheric pressure. Normal atmospheric pressure supports a column of mercury 760 mm high, what is meant by 760 mm Hg or 760 torr .

Boiling temperature of the liquid depends on the pressure: At high altitudes, the lower air pressure allows boiling water to 70 degrees, while at sea level it takes 100 degrees. Cavitation is a form of boiling caused by the pressure drop, it is easier, to make pump cavitation or fluid network with low pressure atmosherique. A system, pumping or fluid flow, must consider this parameter ...

With Mecaflux software,

Atmospheric pressure occurs in the calculation of the pumping system, Indeed, when the tanks are in the open air, the pressure in the reservoirs, is that of the atmospheric pressure. This Air pressure. ambient in the tanks do not take into account the hydrostatic pressure suction or discharge, but is dependent on temperature and altitude.

pression atmospherique

Altitude is a parameter to be included in the tab systems pumps and turbines, a value of ambient pressure is calculated and given as a function of temperature.

pression atmospherique

The pressure in one point of the network is the sum of energies of dynamic and static pressures These transformations of energy are reversible or irreversible

the pressure drops and head losses are irreversible loss of pressure because the head loss is converted into heat or noise that we do not know re-transformed into pressure.

The pressure generated by changing altitude or height of load (hydrostatic pressure) is reversible: If the duct up of 1 meter, and down of 1 meter, the balance is zero:

the pressure generated by the change in velocity (dynamic pressure) is reversible:If for a given flow a converging cone accelerates the fluid the pressure decreases (see Bernoulli), but if another diverging cone, positioned downstream, slows down the fluid to its original speed, the balance of dynamic pressure is zero:

head loss software pressure drop calculation Reynolds number minor head loss head loss Formula head loss major head loss pressure drop hydrailics head loss Flow Regime aeraulic pressure drop major pressure drop Colebrook-White formulas pressure drop Viscosity roughness pipes