Product Description
Intelligent vortex flowmeter
It is a volume flowmeter that measures the volume flow rate of gas, steam or liquid, the volume flow rate under standard conditions or the mass flow rate based on the Karman vortex principle. And can be used as a flow transmitter in automated control systems.
The instrument adopts advanced differential technology, combined with isolation, shielding, filtering and other measures, to overcome the problems of similar products such as poor shock resistance and small signal data disorder. It also adopts unique sensor packaging technology and protective measures to ensure Product reliability. The product has two types: basic type and composite type. The basic type measures a single flow signal and the composite type can measure temperature, pressure and flow at the same time. Each type has an integral or split structure to adapt to different installation environments.
Vortex flowmeter
Principle
If a triangular prism-shaped vortex generator is installed in the fluid, two rows of regular vortices will alternately be generated from both sides of the vortex generator. This vortex is called Karman Vortex street, as shown in Figure (1).
Installing a capacitive detection probe or a piezoelectric detection probe and a corresponding matching circuit into the vortex generator can form a capacitive detection vortex flow/sensor or a piezoelectric detection vortex flow sensor.
Figure (1) The vortex rows are arranged asymmetrically downstream of the vortex generator. Assume that the frequency of vortex occurrence is , the average velocity of the flow of the measured medium is , the width of the upstream surface of the vortex generating body is , and the diameter of the surface body is . According to the Karman vortex street principle, there is the following relationship
〔〕< br/> In the formula, the frequency of Karman vortex generated on one side of the generator
Strohal number
The average flow velocity of the fluid
The width of the cylinder flow surface
The inner diameter of the pipe
Figure (2) In the straight part of the curve table, the vortex release frequency is proportional to the flow rate, which is the measurement range of the vortex flow sensor. As long as the frequency is detected, the flow rate of the fluid in the pipe can be obtained, and the volume flow rate can be obtained from the flow rate.
or/
The instrument constant in the formula.
Mass flow
Volume flow
Medium density
Frequency
YC-LUGB intelligent vortex flowmeter