I'm designing a system to determine pressure drops across thin samples while simultaneously measuring velocity (and through multiplying by area, volumetric flowrate). I need a way of determining how accurate my setup is. The big catch is that what drives the flow is a pressure regulator, so flowrate is entirely dependent on what pressure loss I experience. If I had anything more than my phone this second I would generate and attach more professional pictures.
Moving down the line is the following. First, a pressure regulator downsizes the pressure from the source to whatever value of pressure I want. Then it goes through my clamped sample (in my case I'm dealing with feathers most of the time but it's fairly versatile). Following the test section the cross sectional area of the pipe diverges to double the diameter and then extends for a few inches.
There are three static ports. The first is before the test section. The second is after the test section. The third is after the pipe diverges. My manometer will test between 1 and 2 as well as 2 and 3. 1 and 2 will indicate the pressure loss across the feather/sample. 2 and 3 indicate the static pressure decrease due to the divergence which will allow me to approximate velocity through the Bernoulli equation.
So in essence: how do I validate my manometer readings between both cases? I want to be able to say with confidence that my setup works.