2.англ. Dissertation: 144 p., 7 tables, 43 figures, 64 references, 3 appendixes.
CORIOLIS FLOW METER, DYNAMIC MEASUREMENTS, MEASURING CHANNEL, MEASURING TRANSDUCER, QUANTIZATION, FREQUENCY, TRANSFORMATION FUNCTION, FLOW RATE, MASS FLOW, DENSITY, PETROLEUM PRODUCTS, DYNAMIC AND STATIC METROLOGICAL CHARACTERISTICS, SYSTEMATIC AND RANDOM ERRORS, UNCERTAINTY OF MEASUREMENT RESULTS, AUTOMATED POURING SYSTEM.
The aim of this dissertation is to increase the accuracy of measuring the mass flow rate and density of petroleum products using Coriolis flow meter.
To achieve this goal, it is necessary to solve the following tasks:
- analyze the existing methods and means of measuring liquid mass flow;
- analyze the known methods and means of mass flow measurement according to the principle of the Coriolis force;
- evaluate the influence of non-informative flow parameters, the change of which during measurement with Coriolis flow meter increases the error of mass flow and flow density measurement;
- derive the transformation function that unambiguously links the output value, namely, the mass flow with the input values, namely, the cross-sectional area, stiffness and length of the flow-measuring tube, as well as the change in speed and flow density;
- to estimate the quantization error of Coriolis flow meter on the mass flow measurement channel;
- develop a mathematical model of Coriolis flow meter in the form of a differential equation and evaluate dynamic metrological characteristics;
- to develop a scheme of a functional microprocessor Coriolis flow meter;
- to develop an experimental setup for researching the effect of changing the parameters of the liquid flow on the measurement accuracy of Coriolis flow meter;
- conduct an experimental study of the impact of changing the parameters of the flow of petroleum products, namely diesel and gasoline using the improved information and measurement system of Coriolis flow meter and compare the development with the existing ones;
- to determine the budget of uncertainty components of the measurement results, estimate the uncertainty components of the measurement results, as well as estimate what is caused by the change in the flow rate and the nature of the flow of the liquid flow, mass flow rate and density measured with Coriolis flow meter;
- to improve the method of checking Coriolis flow meter as part of the automated pouring system;
- evaluate the criteria for changing the parameters of the liquid flow, which affect the accuracy of Coriolis flowmeter measurement, which will allow to control the performance of measurements under the specified conditions, which will increase the accuracy of Coriolis flowmeter measurement.
The object of research is the process of measuring the mass flow rate of a liquid flow with variable flow parameters during measurement.
The subject of the study is methods and means of increasing the accuracy of measuring the mass flow rate of liquid of Coriolis flow meter when the parameters of the flow of petroleum products are changed.
Research methods - in the course of the dissertation, research is carried out using the basis of the theory of measurement transformation of non-electric quantities for the development of a mathematical model of Coriolis flowmeter, methods of mathematical, physical and computer modeling using Maple environment in the study of the application of Coriolis force for dynamic measurements of the mass flow of a liquid flow, the basics of the theory of error measurements for evaluating the metrological characteristics of the used tool, methods of mathematical statistics in the processing of measurement results during the study of the convergence of measurement results and estimated uncertainties of measurement results, methods of setting and planning experiments.
The scientific novelty of the obtained results is as follows:
- the improvement of the mathematical model for dynamic measurements, represented by a differential equation, now incorporates variations in flow rate, a feature not addressed in previous models;
- for the first time, a criterion for permissible changes in liquid flow parameters was developed and evaluated. Adherence to this numerical value ensures specified accuracy. When this value is exceeded, regulating devices are employed to normalize flow parameters. This advancement resulted in a threefold increase in mass flow measurement accuracy for gasoline and a twofold increase for diesel fuel;
- the method for checking Coriolis flow meters within automated petroleum pouring systems has been further advanced. Unlike existing methods, it now considers the pulsation index criterion for petroleum product flows, specifically diesel and gasoline.
Research results can be applied at enterprises that use Coriolis flow meters in the technological process as part of an automated pouring system for dynamic measurements of mass flow and liquid flow density.
