a flowmeter in a closed conduit, consisting of a short flared nozzle of reduced diameter inset into the inner diameter of a pipe; used to cause a temporary pressure drop in flowing fluid to determine flow rate via measurement of static pressures before and after the nozzle
For calculation of the emission it is necessary to know the exhaust gas flow (see section 4.8.1.1). For determination of exhaust flow either of the following methods may be used: (a) Direct measurement of the exhaust flow by flow nozzle or equivalent metering system ...
