homework and exercises - To calculate pressure at point in a vertical water pipe of given diameter

Is it possible to calculate pressure at a point in a pipe, where a solenoid valve shall be placed, given that

• the pipe carries water (utility supplied, regular water)


• from an overhead tank (at a certain height from ground)


• height of tank (i.e. max water column height, although not sure if vertical pipe-length should be added to it ?)


• water is flowing purely under the effect of gravity (and atmospheric pressure)



• value is installed at a certain height from ground


• pipe material is PVC


• pipe diameter is say 1.5inches.

Answer

If the fluid is pretty incompressible, the flow rate isn't high and the pipe is wide enough that there aren't surface effects. Then the pressure is simply the height of the head of water above the point multiplied by the density of the fluid.

eg. Water is 0.0361 lbs/cubic inch, so a head of 1ft = 12 inches = 12 * 0.0361 = 0.43 psi