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Frontiers in Energy

, Volume 13, Issue 1, pp 99–106 | Cite as

A novel flow-resistor network model for characterizing enhanced geothermal system heat reservoir

  • Jian Guo
  • Wenjiong Cao
  • Yiwei Wang
  • Fangming JiangEmail author
Research Article
  • 24 Downloads

Abstract

The fracture characteristics of a heat reservoir are of critical importance to enhanced geothermal systems, which can be investigated by theoretical modeling. This paper presents the development of a novel flow-resistor network model to describe the hydraulic processes in heat reservoirs. The fractures in the reservoir are simplified by using flow resistors and the typically complicated fracture network of the heat reservoir is converted into a flow-resistor network with a reasonably simple pattern. For heat reservoirs with various fracture configurations, the corresponding flow-resistor networks are identical in terms of framework though the networks may have different section numbers and the flow resistors may have different values. In this paper, numerous cases of different section numbers and resistor values are calculated and the results indicate that the total number of flow resistances between the injection and production wells is primarily determined by the number of fractures in the reservoir. It is also observed that a linear dependence of the total flow resistance on the number of fractures and the relation is obtained by the best fit of the calculation results. Besides, it performs a case study dealing with the Soultz enhanced geothermal system (EGS). In addition, the fracture numbers underneath specific well systems are derived. The results provide insight on the tortuosity of the flow path between different wells.

Keywords

enhanced geothermal systems flow-resistor network model fracture characteristics heat reservoir 

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Notes

Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (Grant No. 51406213) and the Natural Science Foundation of Guangdong (Grant No. S2013040013967).

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Copyright information

© Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Jian Guo
    • 1
  • Wenjiong Cao
    • 1
  • Yiwei Wang
    • 1
  • Fangming Jiang
    • 1
    Email author
  1. 1.Laboratory of Advanced Energy Systems of CAS Key Laboratory of Renewable Energy, and Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou Institute of Energy ConversionChinese Academy of Sciences (CAS)GuangzhouChina

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