Отправлено: 01.08.08 07:57. Заголовок: Центрифуга и капиллярки

An Integral Method to Calculate Water Saturation in a Centrifuge Experiment to Determine Capillary Pressure
Transport in Porous Media
Springer Netherlands
ISSN 0169-3913 (Print) 1573-1634 (Online)
Volume 29, Number 1 / Октябрь 1997 г.
DOI 10.1023/A:1006586130456
pp. 47-59

a>An Integral Method to Calculate Water Saturation in a Centrifuge Experiment to Determine Capillary Pressure
Techien Chen1

a>(1) CBW Technologies Inc., 35 Edforth Rd NW, Calgary, Alberta, T3A 3V8, Canada


a>Abstract The centrifuge method is commonly used to determine the capillary pressure of a porous medium, and the original approximating method for data analysis developed by Hassler and Brunner is still being used. Its limitations are, however, not well understood. Application to analyze experiments where one of the assumptions was obviously violated had been given in the literature. While the result appeared to be quite reasonable, it was not clear how close was it to reality. One of the objectives of this paper is to review the assumptions that is required to develop this method, so that the experimental condition in which it is applicable can be established. The other objective is to derive a completely different solution technique to this problem. There is no need to assume that the ratio of the inlet radius to the exit radius of the core to the center of the centrifuge be close to 1. With the freedom from this limitation it is, therefore, possible to construct machines at lower cost and to improve on the data quality by allowing longer cores.
centrifuge method - capillary pressure - water saturation - algorithm

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Discussion of Techien Chen, 1997, ‘An Integral Method to Calculate Water Saturation in a Centrifuge Experiment to Determine Capillary Pressure’
Transport in Porous Media
Springer Netherlands
ISSN 0169-3913 (Print) 1573-1634 (Online)
Volume 31, Number 2 / Май 1998 г.
DOI 10.1023/A:1006564023803

Discussion of Techien Chen, 1997, An Integral Method to Calculate Water Saturation in a Centrifuge Experiment to Determine Capillary Pressure
P. Forbes1
(1) Institut Français du Pétrole, 1997-98, Rue Montoyer 75, 1040 Brussels, Belgium

Abstract That discussion recognizes that the above paper deals with one of the main problems for reserves and reservoir evaluation, i.e. the determination of capillary pressure curves using the centrifuge technique. However, it is explained that the subject was not properly addressed and that sections of the paper are out of date, confusing or eventually wrong. For a more relevant overview on the subject, it is recommended to refer to the corresponding survey by the Society of Core Analysts.
centrifuge method - capillary pressure - water saturations - algorithm - core analysis.


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Reply to P. Forbes Discussion of 'An Integral Method to Calculate...', Transport in Porous Media 31, 239–244, 1998
Transport in Porous Media
Springer Netherlands
ISSN 0169-3913 (Print) 1573-1634 (Online)
Volume 41, Number 2 / Ноябрь 2000 г.
Letter to the Editor
Reply to P. Forbes Discussion of ''An Integral Method to Calculate...'', Transport in Porous Media 31, 239–244, 1998
T. Chen1
(1) HBR Technologies Inc., 35 Edforth Rd NW, Calgary, AB, T3A 3V8, Canada
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T. Chen
Email: chent@cadvision.com

References
Chen, T.: 1999, Data reduction in centrifuge capillary pressure experiments, J. Can. Pet. Tech. 38, 20–25.

Hassler, G. I. and Brunner, E.: 1945, Measurement of capillary pressures in small core samples, Trans. AIME 160, 114–123.

Hermansen, H., Eliassen, O., Guo, Y. and Skjaeveland, S. M.: 1991, Capillary pressure from contrifuge – A new direct method, In: Worthington and Longeron (eds), Advances in Core Evaluation II, Reservoir Appraisal, Gordon and Breach (Reviewed Proceedings of the SCA Conference, Eurocas, London, UK, 20–22 May 1991), pp. 453–468.

Ruth, D. W. and Chen, Z. A.: 1995, On the measuement and interpretation of centrifuge capillary pressure curves: The SCA survey data, The Log Analyst 36(9–10), 21–33.

Ruth, D. W. and Wong, S.: 1990, Centrifuge capillary pressure curves, J. Can. Pet. Tech. 29(3), 67–72.