TY - JOUR

T1 - Determining the gas diffusion coefficients in dielectric liquids by the bubble dissolution detecting method

AU - Korobeynikov, S. M.

AU - Ridel, A.

AU - Vagin, D. V.

N1 - This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation ("Modeling and Data Processing of High Technologies" Research Laboratory; Project Code FSUN20200012) . The last test was performed with the help of N.N. Chuprina and M.A. Anikeeva.

PY - 2021

Y1 - 2021

N2 - Bubble dissolution in several liquids is recorded optically. The bubble dissolution rate in a liquid depends on the gas solubility and its diffusion speed in the liquid. Comparing the calculated dissolution curves (using the fitted diffusion coefficient) with the measured curves is a method used to determine the diffusion coefficient. The method was tested on known experimental data on methane diffusion in water, in which the calculated and tabular data differed by about 10%. The calculated dissolution curves noticeably differed when the diffusion coefficient was varied within +/- 5%. The diffusion coefficients of the leading diagnostic gases (hydrogen, methane, ethane, and ethylene) in dielectric fluids in which the solubility coefficients are known (transformer, rapeseed, castor oil, and silicon fluid) were determined. Some anomalies in the observed results may have resulted from the gas purity in the bubbles during bubble formation and the liquid's residual dissolved air concentrations. Differences with the primary data resulted from more careful preparation of clean oils and gases, leading to higher diffusion coefficient values. The proposed measurement and simulation procedure was verified and validated by the experiments. The obtained data and determination methods are essential for applications of gas-liquid systems and can help better understand their behavior.

AB - Bubble dissolution in several liquids is recorded optically. The bubble dissolution rate in a liquid depends on the gas solubility and its diffusion speed in the liquid. Comparing the calculated dissolution curves (using the fitted diffusion coefficient) with the measured curves is a method used to determine the diffusion coefficient. The method was tested on known experimental data on methane diffusion in water, in which the calculated and tabular data differed by about 10%. The calculated dissolution curves noticeably differed when the diffusion coefficient was varied within +/- 5%. The diffusion coefficients of the leading diagnostic gases (hydrogen, methane, ethane, and ethylene) in dielectric fluids in which the solubility coefficients are known (transformer, rapeseed, castor oil, and silicon fluid) were determined. Some anomalies in the observed results may have resulted from the gas purity in the bubbles during bubble formation and the liquid's residual dissolved air concentrations. Differences with the primary data resulted from more careful preparation of clean oils and gases, leading to higher diffusion coefficient values. The proposed measurement and simulation procedure was verified and validated by the experiments. The obtained data and determination methods are essential for applications of gas-liquid systems and can help better understand their behavior.

KW - dissolution

KW - diffusion

KW - hydrogen

KW - bubbles

KW - diagnostic gases

KW - viscosity

KW - transformer oil

KW - MASS-TRANSFER

KW - WATER

M3 - Article

VL - 9

SP - 31

EP - 42

JO - Interfacial Phenomena and Heat Transfer

JF - Interfacial Phenomena and Heat Transfer

SN - 2169-2785

IS - 1

M1 - 2

ER -