What will be the flow velocity of water at 30 psi flowing through a 1/4 inch nozzle? A 1/8 inch nozzle?

The theoretical flow velocity for water through an orifice = v = (2*g*h)^0.5 where h= the head of water in feet above the center of the orifice and g = 32.2 ft/sec^2

The liquid head in feet of water at 30 psi = 30 x 2.31 = 69.3 ft.

therefore v = (2*32.2*69.3)^0.5 = 66.8 ft per second

This will be the velocity thru ANY SIZE of orifice, so will be he same for both the 1/4 & 1/8 inch nozzles.

Actually, each nozzle has what they call a coefficient of velocity, or Cv, which is determined by how much the nozzle exit affects the theoretical maximum flow rate which we calculated above, but that has to be determined by experimentation for each type of nozzle.

The value of Cv would be less than 1.0.

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