Like many other flow meters, venturi meters use a differential pressure measurement to determine the flow rate of a fluid in a system, which means they are relatively easy to use and operate. For this reason, venturi meters are used for many industrial and commercial purposes.
These meters, as their name suggests, operate based on the Venturi effect, which is a phenomenon that occurs when a fluid’s pressure is reduced while flowing through a constricted pipe. The flow meter is made up of several components, the most important of which is a venturi tube. This unique tube is made up of an entry cone, a small diameter tube, and an exit cone.
The tube is placed within a pipeline system and causes the diameter of the pipeline to gradually decrease down to the diameter of the small tube as the fluid passes through the entry cone. The fluid then flows out of the small tube and into the exit cone which slowly returns the pipeline back to its original diameter. This unique design generates the Venturi effect.
The flow meter is also comprised of two pressure measurement devices, one located before the constricted pipe and the other located within the small diameter connecting tube in the venturi tube. The venturi tube creates a pressure differential between these two points, which can be measured by the two pressure sensors. Using a complex formula, the flow meter can determine the volumetric flow rate of the fluid in the system. This formula depends on whether the fluid is compressible and the radius of the pipeline. Other important factors include fluid viscosity and the conical angle of the venturi tube entry and exit cones.
Venturi flow meters are well known for their reliability, long-term performance, and versatility, making them an excellent option for just about any standard metering application. Their reliability and longevity can be attributed to their relatively simple design and lack of moving parts. This allows the device to run very efficiently and significantly reduces the need for regular maintenance.
Compared to many other meters, venturi flow meters also provide exceptionally accurate measurements, and this type of flow meter is often used as the primary standard for flow calibration. While they do provide many benefits, these meters are still limited due to the loss of energy when the fluid travels through the reduced diameter of the venturi tube. However, the conical exit of the venturi meter helps recover much of the consumed energy, making the venturi flow meter an extremely effective and reliable flow metering option.,/p.