10.  Glossary

Pressure differential device; Organe déprimogène

Flowmeter whose mass flow measurement is linked to a pressure difference within the circulating fluid, generated by an artificial restriction of the fluid stream.

Élément primaire : Primary device

Local restriction of the fluid flow within a pipe.

Coefficient de décharge : Discharge coefficient

Corrective parameter used in the equation for calculating the flow rate of a depressurizer. Its value is determined either by testing or by calculation (formulas available in standards where applicable). Its value depends on the type of depressurizer and flow conditions.

Rangeability

Flow range that can be covered by a primary element in operation.