Viscosity-independent fluid flow measurement appts. - has interchangeable compression-expansion nozzles and differential pressure sensor

摘要

The appts. used for measuring fluid flow uses a nozzle (1) and gives results which are practically independent of viscosity. The associated device is insensitive to wear and can be cleaned properly. The fluid flow is subject to a continuous flow channel cross-sectional narrowing followed immediately by a sudden expansion. The static pressure is measured sufficiently for upstream and downstream of the nozzle at points (11) of equal flow speed and equal channel dia. The pressure tapping does not affect the fluid flow. The press. is transferred to the measurement transducer (9) via an incompressible carrier fluid which is electrically insulating. The measurement transformer operates incompressibly and without a time lag. The measurement range is changed by replacing the nozzle with another. A piezoresistive differential pressure transducer (9) is used.