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A Numerical Study on the Thermal Behavior Evaluation of Bentonite Buffer

벤토나이트 완충재의 열적 거동 평가에 관한 수치해석적 연구

Yoon, Chan-Hoon;Choi, Young-Chul;Choi, Heui-Joo
윤찬훈;최영철;최희주

  • Received : 2015.01.30
  • Accepted : 2015.03.17
  • Published : 2015.08.31

Abstract

In this study, laboratory test equipment was designed and installed to evaluate the thermal behavior of bentonite, which is used as a buffer in high-level waste disposal systems. The thermal analysis was conducted to verify the test results using ABAQUS, a finite element analysis code. In view of the seasonal changes seen during the test, the thermal behavior of bentonite with a temperature of outside air was evaluated. Of the cases examined, the results of the analysis model using stainless steel (Case 3) approximates to the test results, showing an error of about 1℃. The results of the thermal analysis into seasonal temperature distributions are consistent with trends seen in lab-test results. These analyses show that the effects of the thermal conductivity of the material surrounding the buffer and outside air temperature, are very important factors in the thermal behavior of bentonite. In the future, it is expected that a moisture saturation test of a bentonite buffer containing a heat source will be carried out. Therefore, the development of a numerical analysis model is required for the prediction and verification of the laboratory test results.

Keywords

Laboratory test;Bentonite;ABAQUS;Thermal conductivity;Thermal behavior

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