This app uses the AGA Report 3 (1990) to calculate the flow of a gas through an orifice plate. It takes as inputs the composition of the gas, and uses that to calculate the compressibility factors, and densities. It will calculate the flow of gas in kg/s and e3m3/d at 15C and 101.325kPaa, as well as show all the factors from the AGA3 1990 calculations. This is useful for verifying flow computer calculations.
The app also includes a sizing tool, which displays a graph of flow rate vs orifice bore size, at the conditions you entered on the first screen.