Nuclear Engineering and Technology

  • 제33권1호
  • /
  • Pages.62-72
  • /
  • 2001
  • /
  • 1738-5733(pISSN)
  • /
  • 2234-358X(eISSN)
한국원자력학회 (Korean Nuclear Society)
권호 표지

Numerical Simulations of the Moisture Movement in Unsaturated Bentonite Under a Thermal Gradient

  • Park, J.W. (Korea Electric Power Corporation) ;
  • K. Chang (Korea Electric Power Corporation) ;
  • Kim, C.L. (Korea Electric Power Corporation)
  • 발행 : 2001.02.01
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초록

The one-dimensional finite element program was developed to analyze the coupled behavior of heat, moisture, and air transfer in unsaturated porous media. By using this program, the simulation results were compared with those from the laboratory infiltration tests under isothermal condition and temperature gradient condition, respectively. The discrepancy of water uptake was found in the upper region of a bentonite sample under isothermal condition between numerical simulation and laboratory experiment. This indicated that air pressure was built up in the bentonite sample which could retard the infiltration velocity of liquid. In order to consider the swelling phenomena of compacted bentonite which cause the discrepancy of the distribution of water content and temperature, swelling and shrinkage factors were incorporated into the finite element formulation. It was found that these factors could be effective to represent the moisture diffusivity and unsaturated hydraulic conductivity due to volume change of bentonite sample.

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참고문헌

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