SUP-LUGB Vortex flowmeter work on the principle of generated vortex and relation between vortex and flow by theory of Karman and Strouhal, which specialize in measurement of steam, gas and liquid of lower viscosity.
Measuring principle
A fluid flowing with a certain velocity and passing a fixed obstruction generates vortices. The generation of vortices is known as Karman’s Vortices.The frequency of vortex shedding is a direct linear function of fluid velocity and frequency depends upon the shape and face width of bluff body. Since the width of obstruction and the inner diameter of the pipe will be more or less constant, the frequency is given by the expression:
f=(St*V)/c*D