The head of the pump refers to the height at which the pump can lift water.
It is an important working performance parameter of the pump, also known as the indenter.
It can be expressed as an increase in the pressure head, kinetic head and potential head of the fluid.
H=(p2-p1)/ρg+(v22-v12)/2g+z2-z1
Where H - head, m;
P1, p2——the pressure of the liquid at the inlet and outlet of the pump, Pa;
V1, v2 - the flow rate of the fluid at the pump inlet and outlet, m / s;
Z1,z2——Import and export height, m;
Ρ——liquid density, kg/m3;
G——gravitational acceleration, m/s2.
The head of the pump usually expressed in H, and the unit is m. The lift of the centrifugal pump is based on the center line of the impeller and consists of two parts. The vertical height from the center line of the pump impeller to the water surface of the water source, that is, the height at which the pump can suck up the water, is called the suction head, referred to as the suction stroke; the vertical height from the center line of the pump impeller to the water surface of the outlet, that is, the pump can press the water up. The height is called the pressurized water lift, which is called the pressure stroke. That is, pump head = water lift head + pressure head. It should be noted that the head indicated on the nameplate refers to the head that the pump itself can produce. It does not contain the loss head caused by the frictional resistance of the pipeline water flow. When choosing a water pump, be careful not to ignore it. Otherwise, there will be no water.
Pump head = net head + head loss Net head is the height difference between the pump's suction point and the high level control point, such as pumping water from the clear water tank and sending it to a high water tank. The net head is the height difference between the suction inlet of the clear water tank and the water tank at the high point.
