Obstruction Meters
Three common obstruction meters are the orifice plate, and the flow nozzle. Flow area profiles of each are shown in Figure 10.2. These meters are usually inserted in-line with a pipe, such as between pipe flanges. This class of meters as a whole operates using similar physical reasoning to relate volume flow rate to pressure drop. Referring to Figure 10.3, consider an energy balance between two control surfaces for an incompressible fluid flow through the arbitrary control volume