Daniel Orifice Flow Calculator uses the ASME MFC-3M 1989 equation to determine the rate of fluid flowing for 2" and larger pipe sizes. It will display the respective ratio, or orifice diameter to pipe diameter, for a given set of input variables. Provided for estimation purposes only, this simple, single-window program assists in sizing an orifice meter and bore size, though the calculated values for the beta ratio are approximate, typically within 2% - 5% for gases and steam, and 1% for liquids.
The program's interface provides fields for inputting the operating temperature and pressure, base specific gravity, pipe size and ID, flow rate and type and differential pressure. I found that there are two calculation variables that the program does not take into account - The Reynolds Number correction and the Expansion factor. If no compressibility correction factor is entered, greater inaccuracies will occur for gas calculations with high operating pressures. Still, Daniel Orifice Flow Calculator provides useful assistance in the calculation of orifice diameters for estimation purposes.