Coriolismittareita

Coriolismittareita are a class of flow measurement devices that determine mass flow rate by exploiting the Coriolis force acting on fluid in vibrating tubes. They are widely used in process industries for precise mass flow measurement, custody transfer, and density determination.

Principle: A flow tube or pair of tubes is driven to vibrate at a resonant frequency. Fluid moving through the vibrating tubes experiences a Coriolis deflection proportional to the mass flow rate. Sensors at the tube ends detect phase shift and amplitude; from these signals, the meter computes mass flow. The tube geometry also yields fluid density, and with temperature sensing, enables temperature-compensated measurements.

Construction: Common forms include U-shaped inline meters and straight-tube configurations. They rely on a drive mechanism to sustain vibration and on sensors to monitor motion. Installation requires careful mounting and alignment; external vibrations and improper straight-run length can affect accuracy.

Advantages and limitations: Coriolis meters offer direct mass flow measurement with high accuracy, wide turndown, and simultaneous density (and sometimes temperature) information. They are versatile across liquids and gases and tolerate a range of viscosities. Limitations include higher cost, sensitivity to external vibrations, and decreased accuracy with highly dirty or multiphase flows; complex fluids can challenge measurement if phase slip occurs.

History and usage: The Coriolis principle dates to 1835, named after Gustave Coriolis. Commercial Coriolis meters appeared in the late 20th century and are now common in chemical, oil and gas, pharmaceutical, and food and beverage industries, as well as in custody-transfer workflows and laboratory instrumentation.