Experimental study on large flow rate monitoring downstream of double elbows using an ultrasonic velocity profile method

This paper describes simple flow rate monitoring using the Ultrasonic Velocity Profile method (UVP), for disturbed flow just after double elbows and large pipes with high Reynolds numbers. This method utilizes the linearity between the flow rate and the velocity at the pipe center under the following flow conditions. The Reynolds number is from 4.1×10⁶ to 5.1×10⁶, the dihedral angle of double elbows is 30° and the distance between double elbows is six diameters. The measuring position is set at two diameters distance downstream of the second elbow. The Computational Fluid Dynamics (CFD) simulations and experimental results indicate that it can monitor flow rate changes with an accuracy of less than 1% under these flow conditions. (author)