There are various types of instruments and equipment used for industrial flow measurement. In the use of industrial instruments, choosing to use different instruments and equipment due to different usage environments can also be considered as a form of instrument selection nowadays. However, for various similar but different instruments, users may inevitably make selection errors during use. Below is a comparison between vortex street and turbine flowmeter to facilitate our later selection.
Although these two types of instruments have similar names, they are not the same type of instrument in use.
The vortex flowmeter is designed and manufactured based on the Karman vortex principle. The principle of fluid oscillation is applied to measure flow rate. When the fluid passes through the vortex flow transmitter in the pipeline, two columns of vortices proportional to the flow velocity are alternately generated up and down behind the vortex generator in the triangular column. The release frequency of the vortices is related to the average velocity of the fluid flowing through the vortex generator and the characteristics of the vortex generator.
A turbine flowmeter is an instrument that uses a multi blade rotor (turbine) to sense the average flow velocity of a fluid and derive the flow rate or total amount from it.
Turbine flowmeters are widely used for measuring objects such as petroleum, organic liquids, inorganic liquids, liquefied gas, natural gas, coal gas, and low-temperature fluids. It has a simple structure, few processed parts, light weight, easy maintenance, high flow capacity (the same caliber can pass through a large flow rate), and can adapt to high parameters (high temperature, high pressure, and low temperature).
The vortex flowmeter used in the market is mainly used for flow measurement of industrial pipeline media fluids, such as gases, liquids, vapors, and other media. Its characteristics are small pressure loss, large range, high accuracy, and almost unaffected by parameters such as fluid density, pressure, temperature, viscosity, etc. when measuring volumetric flow rate under working conditions. No movable mechanical parts, therefore high reliability and low maintenance.
In the current market usage, we users should know that flow meters should be used within the technical parameters of the working pressure and temperature range of the medium. Do not deliberately choose instruments with high pressure levels and ultra-high temperatures. Choose instruments based on actual working pressure and temperature, as the latter is more expensive.
The lower limit flow rate of a vortex flowmeter depends on the working density and viscosity of the medium, and its upper limit flow rate is generally not affected by the pressure and temperature of the medium. Therefore, determining the flow range only requires determining the actual available lower limit flow rate. After calculating the lower limit flow rate, the corresponding caliber can be determined by checking the flow range table.
The selection of flow meters should avoid using flow rates that operate at the lower limit, so the diameter of the flow meter should be as small as possible to obtain a larger flow rate and flow range.