Method of Control of Liquid Environment and Method of Assessing the Uncertainty of Measurement Results of Coriolis Flow Meter

Abstract

The purpose of the performed work is to improve the accuracy of measuring the mass flow rate and density of a liquid by controlling the flow parameters of a fluid medium and evaluating the uncertainty component of the measurement results due to the fluidity of the parameters of the measured liquid flow, the characteristics of which differ from those of water. For this purpose, we analyzed modern research. Based on the results of the analysis of the Coriolis flowmeter structure and the conversion equation of the measuring instrument, the factors that change during measurements affect the accuracy of the flowmeter's measurement of mass flow and density of the liquid are analyzed. Based on the results of the analysis, the main flow parameters that reduce the measurement accuracy of the Coriolis flowmeter and cause additional measurement uncertainty are identified. The budget of the measurement uncertainty components is described and additional uncertainty components of the measurement results are calculated, and the budget includes uncertainty components that take into account factors of changes in the flow rate and the nature of the flow of the fluid whose mass and density are measured by the Coriolis flowmeter. The following parameters are investigated: flow velocity change, pressure change in the pipeline upstream and downstream of the flowmeter, and temperature change. A method for controlling the parameters of the fluid medium has been developed. Criteria for controlling the flow medium depending on the pulsation index are proposed. The paper describes a method for estimating the uncertainty component of measurement results due to fluidity of the medium and changes in the velocity and pressure of the measured fluid flow, the characteristics of which differ from those of water. A method for changing the parameters of the fluid flow is proposed, which will allow controlling the measurement under specified conditions and increasing the accuracy of measuring the mass flow rate of a fluid whose characteristics differ from those of water.