THE PRACTICE ON D-N 1400 MM VENTURI TUBES

In order to meet the requirement presented by a water supply company t o measure the flow rate in the pipes with a very large diameter, Kaife ng Instrument Factory, China, manufactured 13 sets of D-n 1400 mm clas sical Venturi tubes in 1982 and 1992, respectively. As the diameter of the Venturi tubes is outside the scope covered by the ISO5167, the in ternational standard cannot be directly adopted for determining the di scharge coefficients. So the authors designed these 13 Venturi tubes o n the basis of using the similarity criterion and the method of practi cal calibration. The dimension and the profile of the Venturi tubes st rictly followed the rules stipulated in ISO5167, and the calibrations were carried out individually on a large scale water flow rig. The exp erimental results show that the consistency of discharge coefficients of the 13 Venturi tubes is quite good. (C) 1998 Elsevier Science Ltd. All rights reserved.