Ultra-fast x-ray tomography for multi-phase flow interface dynamic studies

M. Misawa; I. Tiseanu; H.-M. Prasser; N. Ichikawa; M. Akai

doi:10.1515/kern-2003-0046

Article

Ultra-fast x-ray tomography for multi-phase flow interface dynamic studies

M. Misawa , I. Tiseanu , H.-M. Prasser , N. Ichikawa and M. Akai

Published/Copyright: March 11, 2022

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From the journal Kerntechnik Volume 68 Issue 3

Abstract

The present paper describes the concept of a fast scanning Xray tomograph, the hardware development, and measurement results of gas-liquid two-phase flow in a vertical pipe. The device uses 18 pulsed X-ray sources activated in a successive order. In this way, a complete set of 18 independent projections of the object is obtained within 38 ms, i. e. the measuring rate is about 250 frames per second. Finally, to evaluate the measurement capability of the fast X-ray CT, a wire-mesh sensor was installed in the flow loop and both systems were operated for the same two-phase flow simultaneously. Comparison of the time series of the cross section averaged void fraction from both systems showed sufficient agreement for slug flow at large void fractions, while the fast CT underestimated the void fraction of bubbly flow especially in low void fraction range. For the wire-mesh sensor, coerced deformation of slug bubble interface was found. Further hardware improvement is in progress to achieve better resolution with the fast X-ray CT scanner.

Abstract

Der Beitrag beschreibt das Konzept eines schnellen Röntgentomographen, die Hardwareentwicklung und Messergebnisse aus einer Zweiphasenströmung eines Flüssigkeits-Gas-Gemischs in einer vertikalen Rohrleitung. Das Gerät verfügt über 18 gepulste Röntgenquellen, die in schneller Folge aktiviert werden. Auf diese Weise wird ein vollständiger Satz aus 18 Projektionen des Objekts innerhalb von 38 ms gewonnen. Die Messfrequenz beträgt demzufolge ca. 250 Bilder pro Sekunde. Um das System zu testen, wurde ein Gittersensor in die Strömungsschleife eingebaut. Beide Geräte wurden gemeinsam zur Aufnahme der gleichen Zweiphasenströmung genutzt. Der Vergleich des Zeitverlaufs des querschnittsgemittelten Gasgehalts zeigt eine gute Übereinstimmung zwischen beiden Verfahren im Gebiet der Pfropfenströmung. Bei einer Blasenströmung kommt es zu einer Unterbewertung des Gasgehalts durch den Röntgentomographen. In Bezug auf den Gittersensor wurde eine Deformation der Großblasen gefunden. Zukünftige Hardware-Verbesserungen zur Erhöhung der Auflösung des Röntgentomographen sind geplant.

Acknowledgement

A part of this study was financially supported by the Budget for Nuclear Research of the Ministry of Education, Culture, Sports, Science and Technology, Based on the screening and counseling by the Atomic Energy Commission. Also, a part of this study has been performed as a public subscription project of practical and innovative nuclear power development by Institute of Advanced Energy (IAE) and Japan’s Ministry of Economics, Trade and Industry (METI).

References

1 Bord, S.; Clement, A.; Lecomte, J. C.; Marmeggi, J. C.: An X-ray tomography facility for I.C. industry at STMicroEinzugelectronics Grenoble. J. Microelectronics Engineering 1 (2002)10.1016/S0167-9317(02)00523-3Search in Google Scholar

2 Gondrom, S.; Schropfer, S.: Digital computed laminography and tomosynthesis – functional principles and industrial applications. Proc. Computerized Tomography for Industrial Applications and Image Processing in Radiology, March 15–17, Berlin, Germany, 1999Search in Google Scholar

3 Morooka, S.; Ishizuka, T.; Iizuka, M.; Yoshimura, K.: Experimental study on void fraction in a simulated BWR Fuel Assembly (Evaluation of Cross-sectional averaged void fraction). Nuclear Engineering and Design 114 (1989) 9110.1016/0029-5493(89)90128-3Search in Google Scholar

4 Mitsutake, T.; Morooka, S.; Sukuki, K.; Tsunoyama, S.; Yoshimura, K.: Void Fraction Within Rod Bundles Based on Three-fluid Model and Comparison with X-ray CT Void Data. Nuclear Engineering and Design 120 (1990) 20310.1016/0029-5493(90)90373-6Search in Google Scholar

5 Tiseanu, I. and Simon, M.: High-resolution cone-beam tomography for two-phase flow diagnostics. Proc. of 2nd International Symposium on Two-Phase Flow Modelling and Experimentation, May 23–26, Pisa, Italy, 1999Search in Google Scholar

6 Kumar, B. S.; Moslnian,D.; Dudukovic,M. P.:AGamma Ray Tomographic Scanner for Imaging Void Fraction Distribution in Bubble Columns. Flow Meas. Instru.6 (1995) 6110.1016/0955-5986(95)93459-8Search in Google Scholar

7 Hori, K. and Akai, M.: Measurement of Variation in Void Fraction Distribution by the Fast X-ray CT Scanner. Graphic Simulation and Visualization of Multiphase Flow 21 (1993) 96Search in Google Scholar

8 Hori, K.; Fujimoto, T.; Kawanishi, K.: Application of cadmium telluride detector to high speed X-ray CT scanner. Nucl. Instr. and Methods in Physics Research A 380 (1996) 39710.1016/S0168-9002(96)00312-9Search in Google Scholar

9 M. Misawa, K.; Ichikawa, N.; Akai, M.; Hori, K.; Tamura, K.; Matsui, G.: Development of Fast X-ray CT System for Transient TwoPhase Flow Measurement. Proc. 6th Int. Conf. Nucl. Eng., ICONE-6383, San Diego, USA, 1998Search in Google Scholar

10 Prasser, H.-M.; Scholz, D.; Zippe, C.: Bubble size measurement using wire-mesh sensors. Flow Measurement and Instrumentation 12 (2001) 29910.1016/S0955-5986(00)00046-7Search in Google Scholar

Received: 2003-02-18

Published Online: 2022-03-11

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https://doi.org/10.1515/kern-2003-0046