Calculation of pumps
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This post was last edited by kaminocmyhc on 2011-2-10 16:03. Could someone please explain how to calculate the pump’s head, the outer diameter of the impeller, and its rotational speed? What is the formula?
The pump head calculation formula, head, H, represents the effective energy gained by a unit mass of liquid after passing through the pump. It is an important operational parameter of the pump, also known as head. It can be expressed as an increase in the pressure head, kinetic energy head, and potential energy head of the fluid, that is, H = (p2 – p1)/ρg + (c2 – c1)/2g + z2 – z1. Here, H represents the head, in meters ； p1, p2 —— Pressure of the liquid at the inlet and outlet of the pump, Pa ； c1, c2 —— flow velocity of the fluid at the inlet and outlet of the pump, m/s ； z1, z2 —— inlet and outlet heights, m ； ρ — liquid density, kg/m3 ； g — gravitational acceleration, approximately 9.81 m/
There are various methods for calculating the head of a pump; it can be done using the Bernoulli equation as described above, or by employing the formula for the effective power of the pump – the choice depending on the available information. As for the outer diameter of the impeller and the rotational speed, there are also various formulas for calculation, but they are all interrelated formulas. In summary, the three parameters proposed by the original poster seem to be data that can be obtained directly; for example, such data is available when purchasing or selecting a specific model of pump, and there is no particular formula needed to calculate these parameters.
You can tell the supplier what you need and ask them to help you calculate the appropriate option; that would be better.
You can tell the supplier what you need
Some pump manufacturers are not very professional either; consult them and then verify it on your own
In my opinion, it is necessary to select an appropriate head height first, and then use Bernoulli’s principle to calculate various values~~