Variable Area Water Flowmeters for Thermal Gas Mass Flow Meters

Variable Area Water Flowmeters for Thermal Gas Mass Flow Meters

Vortex flow measurement is based on the Karman Vortex Street principle, where a cylindrical object is vertically inserted into the measuring tank. When the fluid passes through the cylindrical object, under certain conditions, two rows of regular vortices are generated alternately on both sides of the column. As shown in the figure below, these two rows of vortices are called "Carmen vortex streets". When d/D=0.281, the released vortices are the most stable. The frequency of Carmen vortex street release is related to the velocity of fluid flow and the width of the column, and can be simply expressed by the following formula:
F=St × V/d
F: Release frequency of Carmen vortex street
St: coefficient (referred to as Strouhal number)
V: Fluid flow velocity
D: Column width

Basic characteristics
Better seismic performance
Low lower limit flow rate, up to 1/2~1/4 of conventional vortex flowmeter
Wide range ratio, usually up to 1:30~1:50
Simple debugging operation with HART communication function (optional)
Instantaneous flow display, cumulative total display, percentage display, frequency display
4-20mA output, 0-5KHZ frequency output, vortex pulse output
Using Chinese and English operating menus, easy to read and understand.