Improving the quality of turbine flowmeters on the basis of the use of a rotor with internal screw relief

Abstract

This research aims to improve the quality of measurement of fluid flow rates by turbine flowmeters. The quality criteria for a turbine flowmeter include the accuracy of measurement and the cost of its implementation. To compare the criteria, the article presents a hydrodynamic simulation of the movement of the flow of the working medium through the rotors of the flowmeters of the developed and standard types. The developed type of rotor is a hollow shaft with an internal screw relief. A propeller type of rotor was used as standard. Based on the results of the literature analysis, the purpose of the study was reduced to determining the characteristics of hydraulic resistance that affect the linearity of the flow-pressure characteristics of the flowmeter rotor. The tasks of hydrodynamic computer simulation included its implementation for various indicators of the viscosity of the working fluid - from low-viscosity to high-viscosity. It showed that the use of a rotor with an internal screw relief in a flowmeter reduces the hydraulic resistance of the flow by more than 2 times for any viscosity of the working medium compared to a propeller-type rotor, which significantly reduces the energy costs for moving the flow. At the same time, the linearity of characteristics for both types of flowmeter rotors remains approximately the same in the studied range of characteristics, which indicates a similar accuracy of parameter measurements. Keywords: turbine flowmeter; viscosity; hydraulic resistance; oil transportation; computational fluid dynamics; CFD.