Quantitative tomographic measurements of opaque multiphase flows

GEORGE,DARIN L. ; TORCZYNSKI,JOHN R. ; SHOLLENBERGER,KIM ANN ; O' ; HERN,TIMOTHY J. ; CECCIO,STEVEN L.

Sandia National Laboratories

关键词: Electric Impedance;    Void Fraction;    Two-Phase Flow;    Multiphase Flow;    42 Engineering;   

DOI  :  10.2172/752051
RP-ID  :  SAND2000-0443
RP-ID  :  AC04-94AL85000
RP-ID  :  752051

美国|英语

来源: UNT Digital Library

【 摘 要 】

An electrical-impedance tomography (EIT) system has been developed for quantitative measurements of radial phase distribution profiles in two-phase and three-phase vertical column flows. The EIT system is described along with the computer algorithm used for reconstructing phase volume fraction profiles. EIT measurements were validated by comparison with a gamma-densitometry tomography (GDT) system. The EIT system was used to accurately measure average solid volume fractions up to 0.05 in solid-liquid flows, and radial gas volume fraction profiles in gas-liquid flows with gas volume fractions up to 0.15. In both flows, average phase volume fractions and radial volume fraction profiles from GDT and EIT were in good agreement. A minor modification to the formula used to relate conductivity data to phase volume fractions was found to improve agreement between the methods. GDT and EIT were then applied together to simultaneously measure the solid, liquid, and gas radial distributions within several vertical three-phase flows. For average solid volume fractions up to 0.30, the gas distribution for each gas flow rate was approximately independent of the amount of solids in the column. Measurements made with this EIT system demonstrate that EIT may be used successfully for noninvasive, quantitative measurements of dispersed multiphase flows.