Orifice Flow-UWP app is for Windows 10 devices that facilitates measurement of fluid flow in pipes and conduits using orifice plates that are very common in industrial applications. This app quickly computes the flow rates for liquid and gases based on standard parameters as per the model shown. Users can pick any fluid from a list of fifteen most common fluids used in industrial applications. Therefore, this app can be a very helpful tool for practicing engineers and designers in measurement of flows in pipes and conduits. A case study on CO2 flow rate is shown in the screen shot. The result is consistent with other methods used by the industry in computation and difference is less than 0.5%. Flow models with governing equations are given separately for quick reference. List of fluids: Air, Steam, Water, Nitrogen, Oxygen, Hydrogen, Helium, CO2, Methane, Ethane, Chlorine, Ammonia, Argon, Hydraulic oil, HFC (R410A). Orifice Design: App gives four standard orifice design with recommended discharge coefficients as shown in the screen shot. It also gives the details of different parameters used in the computation of flow rates of liquid and gases. This model is valid even for nozzles, venturi-tubes and meters for which the default discharge coefficient (Cd) is unity. Orifice Parameters: Fluid inlet temperature and pressure, orifice geometry, pressure differential using standard pressure taps (ISO 5167), are the standard parameters required in the computation. Based on the orifice geometry, recommended discharge coefficient Cd is used. However, users can edit this using manufacturer’s data for more accurate results. Unit of Measurement: Users can choose either SI and USCS unit standards. Based on type fluids the unit for the flow rate is shown accordingly. You can use our complimentary unit conversion app to convert units for both input and output. Help Notes: Help screen is provided with guide lines and steps to follow in flow rate computation and also o report any issues. Model equations are provided in separate screen for reference.