If this question relates to the fuel system , A gravity feed system would need to have the fuel tanks in the wings that would need to be above the level of the engines, IE: in a high wing aircraft. A pumped system would be used in a low wing aircraft or in a engine that required a constant fast fuel flow.
The boiler feed pump pumps hot feedwater into the boiler. The boiler pressure is to high for water to flow into it by gravity, so a pump is required.
Gravity feed from a tank on the roof;pump from a private cistern;gravity from a municipal supply;pump from some other limited supply, if permitted by local authority.
some use a mechanical geared pump but most smaller bikes use suction and gravity feed fuel lines
There isn't one. Pressure in a piping system will be determined by the pump, or head of water if it is a gravity feed system.
A digester feed pump forces water to a boiler. It works by transferring cool water to the boiler to be heated.
The feed pump promote the flow of raw milk from balance tank to plate heat exchanger.
it is 500N
Pump efficiency can not be taken as given.
If you can't use gravity you have to use a pump of some sort.
bkw required = (head * flow* specific gravity) / (efficiency of pump*367.2)
Boiler feed pump's suction pressure be aprox. 15Kg/cm2 and discharge pressure be 180Kg/cm2. So the balancing line balance the pressure and protect the boiler feed pump. my quastion is that what is the working principal of balancing leak off
Yep. In most cases I find the pump at fault.