Abstract
This paper discusses the principle and mathematical method to measure the phase fractions of multiphase flows by using a dual-energy gamma-ray system. The dual-energy gamma-ray device is composed of radioactive isotopes of241 Am and137 Cs with emission energies of 59.5 keV and 662 keV respectively. A rational method to calibrate the absorption coefficient was introduced in detail. The statistical error has been analyzed on the basis of the accurate absorption coefficient which enables determination phrase fractions almost independent of the flow regime. Improvement has been achieved on the measurement accuracy of phase fractions.
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Abro, E., Johansen, G.A., 1999. Improved void fraction determination by means of multi-beam gamma-ray attenuation measurements.Flow Measurement and Instrumentation,10:99–108.
Boyer, C., Fanget, B., 2002. Measurement of liquid flow distribution in trickle bed reactor of large diameter with a new gamma-ray tomographic system.Chemical Engineering Science,57:1079–1089.
Chen, J.W., Gupta, P., Degaleesan, S., Al-Dahhan, M.H., Dudukovic, M.P., Toseland, B.A., 1998. Gas holdup distributions in large-diameter bubble columns measured by computer tomography.Flow Measurement and Instrumentation,9:91–101.
Grassler, T., Wirth, K.E., 2001. Dual-Energy X-Ray Tomography in Process Engineering—A Non-Intrusive Technique to Characterise Vertical Multiphase Flows. 2nd World Congress on Industrial Process Tomography, Hannover, Germany.
Kemoun, A., Ong, B.C., Gupta, P., Al-Dahhan, M.H., Dudukovic, M.P., 2001. Gas holdup in bubble columns at elevated pressure via computed tomography.International Journal of Multiphase Flow,27:929–946.
Stahl, P., von Rohr, P.R., 2004. On the accuracy of void fraction measurements by single-beam gamma-densitometry for gas-liquid two-phase flows in pipes.Experimental Thermal and Fluid science,28:533–544.
Yin, F.H., Afacan, A., Nandakumar, K., Chuang, K.T., 2002. Liquid holdup distribution in packed columns: gamma ray tomography and CFD simulation.Chemical Engineering and Processing,41:473–483.
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Zhi-biao, L., Dong-hui, L. & Ying-xiang, W. Study on absorption coefficients of dual-energy γ-rays in determining phase fractions of multiphase flows. J. Zhejiang Univ. Sci. A 6, 1416–1419 (2005). https://doi.org/10.1631/jzus.2005.A1416
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DOI: https://doi.org/10.1631/jzus.2005.A1416