Description

Working Principle:

When a bluff vortex generator (bluff body) is set in the fluid, two regular vortex generators are alternately generated from both sides of the vortex generator. Vortex, this kind of vortex is called Karman vortex street.

The rows of vortices are arranged asymmetrically downstream of the vortex generator. Suppose the frequency of vortex occurrence is f, the average velocity of the incoming flow of the measured medium is V, the width of the vortex generating body is d, and the diameter of the surface body is D. According to the principle of Karman vortex street, there is the following relationship:

f=StV/d

In the formula: f- the frequency of the Karman vortex generated on one side of the generator
St-Strohal number (dimensionless number)
V-fluid Average velocity
d – the width of the vortex generator

It can be seen that the instantaneous flow can be calculated by measuring the separation frequency of Carmen Vortex. Among them, the Strohal number (St) is a dimensionless unknown.