Investigation of two-component flow “liquid-gas” influence on a coriolis flowmeter dynamic parameters

In connection with the development of methods for determining the volume-mass parameters of “liquid-gas” performed by a team of scientists from the South Ural State University, the paper presents the results of full-scale tests and modeling of the operation of a Coriolis flowmeter with a gas-liquid mixture flow. The study aims to establish the causes of reduction of measurement accuracy by the device with an increase in the gas phase in the fluid flow. For this purpose, a series of pouring tests were performed on a specialized stand with the possibility of injecting a gas fraction into the liquid flow. The gas volume fraction in the fluid was calculated. A simulation model of the measuring tube of the Coriolis flowmeter was built and a non-stationary calculation was performed in the mechanical and hydrodynamic module with two-way transmission of pressure and displacement fields at each time step. The gas-liquid mixture was modeled using the VOF model. Based on the simulation results, it was found that the reduction in mass flow measurement accuracy is affected by the physics of the process occurring in the “flow tube - gas-liquid flow” system. A comparative analysis of the calculation and test results was performed, and their qualitative coincidence was shown. It was found that in the case of a two-phase flow, the control electronics and signal processing algorithms are not the main source of measurement error.