Calculating Gauge Pressure of Faucet at home without a pressure gauge
Hey everyone, I’m trying to measure the water supply pressure from my outdoor tap (sillcock) using Bernoulli’s equation and a bucket test rather than buying a pressure gauge. Wanted to see if my method is valid before I go ahead with it.
Here’s my setup:
I know my indoor supply pipe diameter is 1/2 inch (D1)
I’ll measure the internal outlet diameter of the sillcock with calipers (D2)
I’ll measure volumetric flow rate by timing how long it takes to fill a known volume bucket (Q = V/t)
From Q and both diameters I can get both velocities using continuity: V = Q/A
Then apply Bernoulli between the supply pipe (P1 unknown) and the outlet (P2 = atmospheric) with delta Z = 0 since the bucket is at roughly the same height as the tap
My concern is that this gives dynamic pressure while water is flowing rather than true static supply pressure. Will this method give a reasonably accurate result? And is dynamic pressure actually more relevant for sizing a drip irrigation pressure regulator anyway since the system will always be flowing?
Any feedback appreciated, thanks