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A Study on Applicability of Equivalent Continuum Flow Model in DFN Media

DFN 매질에 대한 등가연속체 유동모델의 적용 가능성 평가에 관한 연구

  • Received : 2017.10.09
  • Accepted : 2017.10.25
  • Published : 2017.10.31

Abstract

The correlation analysis between the results obtained from DFN flow model and equivalent continuum flow model were conducted on total of 72 DFN blocks having various fracture geometry and domain size. A strong linear relation seems to exist between the two approaches under condition that normalized relative error for continuum behavior (ER) is less than 0.2, and the results from both methods are found to almost identical. To explore the field applicability of equivalent continuum flow model in DFN media, a total of 48 numerical schemes related to inflow of underground circular openings were implemented under various DFN configurations. The equivalent continuum flow model in DFN media with a constant hydraulic aperture was evaluated as valid. However, as the anisotropy increases due to variation of the hydraulic aperture, the results are likely to be overestimated compare to the DFN flow model.

Keywords

Discrete fracture network;Equivalent continuum flow model;DFN flow model;Numerical experiments

Acknowledgement

Supported by : 한국연구재단

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