Experimental and Computational Multiphase Flow

, Volume 2, Issue 3, pp 174–185 | Cite as

Comparison of data processing algorithm performance for optical and conductivity void probes

  • C. Mills
  • J. P. SchlegelEmail author
Research Article


In commercial nuclear reactors, heat exchangers, and bubble column reactors, two-phase flows are present. When predicting the safety and process efficiency of these systems, it is necessary to model the behavior found in them. The most common model used in two-phase flows is the two-fluid model due to its practicality. In the two-fluid model, two key parameters are the void fraction (VF, also known as the gas fraction or gas holdup) and interfacial area concentration (IAC, also known as interfacial area density). In order to produce accurate results, the bubbles are separated into groups based on the transport properties. When benchmarking models, experimental data are required. In many cases the experimental data are produced with the use of intrusive conductivity or optical probes. Recently a new data processing algorithm was developed to improve bubble interface identification and implement a method to group bubbles based on diameter rather than chord length. In this paper, the new data processing algorithm is evaluated by comparing the results when using both conductivity and optical probes. At a data acquisition frequency of 22 kHz, the optical probe collected more bubbles than the conductivity probe using the old algorithm. The new algorithm results in similar bubble counts for both instruments. There is a shift in bubbles from Group 1 to Group 2 in both the optical and conductivity probes. The new bubble size calculation means that several bubbles, which were previously classified as “spherical/distorted”, are now classified as “cap/slug/churn” bubbles for both the optical and conductivity probes. However due to low sample rates used in this research, the IAC is larger for the conductivity probe when compared to the optical probe by 10% to 60%. While some of these changes were expected, the increase in the IAC was larger than the reported uncertainty of the instruments.


void fraction interfacial area conductivity probe two-group methods 


  1. Abuaf, N., Jones, O. C. Jr., Zimmer, G. A. 1978. Optical probe for local void fraction and interface velocity measurements. Office of Scientific and Technical Information.CrossRefGoogle Scholar
  2. Danel, F., Delhaye, J. M. 1971. Sonde optique pour mesure du taux de présence local en écoulement diphasique. Mesure-Regulation-Automatisme, 36: 99–101.Google Scholar
  3. Farag, H. I., Mejdell, T., Hjarbo, K., Ege, P., Lysberg, M., Grislingas, A., de Lasa, H. 1997. Fibre optic and capacitance probes in turbulent fluidized beds. Chem Eng Commun, 157: 73–107.CrossRefGoogle Scholar
  4. Frijlink, J. J. 1987. Physical aspects of gassed suspension reactors. Ph.D. Thesis. Delft University of Technology, Netherlands.Google Scholar
  5. Galaup, J. P., Delhaye, J. M. 1976. Utilization of the miniaturized optical probes for void fraction and gas velocity measurements in two-phase flow. La Houille Blanche, 1: 17–30.CrossRefGoogle Scholar
  6. Ishii, M. 1975. Thermo-Fluid Dynamic Theory of Two-Phase Flow. Paris: Eyrolles.zbMATHGoogle Scholar
  7. Ishii, M., Kim, S. 2001. Micro four-sensor probe measurement of interfacial area transport for bubbly flow in round pipes. Nucl Eng Des, 205: 123–131.CrossRefGoogle Scholar
  8. Ishii, M., Kim, S., Uhle, J. 2002. Interfacial area transport equation: model development and benchmark experiments. Int J Heat Mass Transfer, 45: 3111–3123.CrossRefGoogle Scholar
  9. Ishii, M., Revankar, S. T. 1991. Measurement of interfacial area using four sensor probe in two phase flow. NASA STI/Recon Technical Report N, 91.Google Scholar
  10. Kataoka, I., Ishii, M., Serizawa, A. 1994. Sensitivity analysis of bubble size and probe geometry on the measurements of interfacial area concentration in gas-liquid two-phase flow. Nucl Eng Des, 146: 53–70.CrossRefGoogle Scholar
  11. Kim, S. 1999. Interfacial area transport equation and measurement of local interfacial characteristics. Ph.D. Thesis. Purdue University.Google Scholar
  12. Kim, S., Fu, X. Y., Wang, X., Ishii, M. 2001. Study on interfacial structures in slug flows using a miniaturized four-sensor conductivity probe. Nucl Eng Des, 204: 45–55.CrossRefGoogle Scholar
  13. Miller, N., Mitchie, R. E. 1969. The development of a universal probe for measurement of local voidage in liquid-gas two-phase flow systems. Two-Phase Flow Instrumentation, 82–88.Google Scholar
  14. Miller, N., Mitchie, R. E. 1970. Measurement of local voidage in liquid/gas two phase flow systems using a universal probe. J Brit Nucl Energy Soc, 9: 94–100.Google Scholar
  15. Mills, C. S. L., Schlegel, J. P. 2019. Interfacial area measurement with new algorithm for grouping bubbles by diameter. Exp Comput Multiph Flow, 1: 61–72.CrossRefGoogle Scholar
  16. Neal, L. G., Bankoff, S. G. 1963. A high resolution resistivity probe for determination of local void properties in gas-liquid flow. AIChE J, 9: 490–494.CrossRefGoogle Scholar
  17. Talley, J. D., Worosz, T., Kim, S. 2015. Characterization of horizontal air-water two-phase flow in a round pipe part II: Measurement of local two-phase parameters in bubbly flow. Int J Multiphase Flow, 76: 223–236.CrossRefGoogle Scholar
  18. Tian, D. G., Yan, C. Q., Sun, L. C. 2015. Model of bubble velocity vector measurement in upward and downward bubbly two-phase flows using a four-sensor optical probe. Prog Nucl Energ, 78: 110–120.CrossRefGoogle Scholar
  19. Xue, J. L., Al-Dahhan, M., Dudukovic, M. P., Mudde, R. F. 2008. Bubble dynamics measurements using four-point optical probe. Can J Chem Eng, 81: 375–381.CrossRefGoogle Scholar

Copyright information

© Tsinghua University Press 2019

Authors and Affiliations

  1. 1.Department of Mining and Nuclear EngineeringMissouri University of Science and TechnologyRollaUSA

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