I am working on an air flow vs pressure chart for a variety of valve components for work and I am hoping someone may know where I could get some comparative baseline data. My setup is a 4' long, 2" diameter PVC pipe with one end connected to a large air compressor tank with a ball valve for regulating the flow. Near the other end, I have an air flow transducer (Omega FMA-906) and a pressure transducer (Omega PX303). The end of the pipe is reduced by a series of graduated fittings that terminate at different ends that are designed to fit the valves I am testing. I am able to check my pressure readings with an analog pressure gauge, but I don't have the same ability with the flow without significant setup changes. I am hoping there is some type of baseline data available for typical flows in a pipe with a constricted end. If anyone could point me to a resource for that data, that would be great!!