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Integrated Experimental-Numerical Approach to Investigate the Heat Transferring Effect of Carbon Nanotube on the Concrete Slab

실내실험 및 수치해석을 통한 Carbon Nanotube의 콘크리트슬래브 열전달 효과 검증

  • Kim, Hee Su (Department of Civil Engineering, Kangwon National University) ;
  • Ban, Hoki (Department of Civil Engineering, Kangwon National University)
  • Received : 2018.10.21
  • Accepted : 2018.11.12
  • Published : 2019.01.01

Abstract

This paper presents a method to deice concrete pavement with carbon nanotube(CNT) as an heating material so as to avoid the adverse effects of conventional deicing method such as salt on the structure, function and environment. To this end, laboratory tests integrated with numerical simulations were conducted. In the laboratory tests, the CNT was embedded inside the concrete slab and generated the heat up to the target temperature of $60^{\circ}C$ in the freezer at temperature of $-10^{\circ}C$. Then, the surface temperature was measured to investigate how far the heat transfers on the surface at temperature of above $0^{\circ}C$. Also, three different spacings of 15, 20 and 30cm between CNTs were conducted to determine the maximum allowable spacing of CNT. Along with these experimental tests, heat transferring analysis conducted to validate the test results.

본 연구에서는 염화물, 전열선 등을 이용한 기존 결빙방지기술의 문제점인 도로 및 주변 구조물 내구성 저하, 많은 인력과 유지비용이 필요로 하는 등을 해소하고자 Carbon nanotube(CNT)를 이용한 결빙방지기술에 대한 기초자료로 실내실험과 수치해석 방법을 제시하였다. 이를 위해 실내실험과 수치해석을 통한 검증을 수행하였다. 실내실험은 CNT를 콘크리트 실험체 중심에 1개 삽입 후 냉동 Chamber를 이용하여 주변온도 및 실험체의 내부온도를 $-10^{\circ}C$로 유지하였으며, CNT를 $60^{\circ}C$로 발열시켰다. 콘크리트 표면 온도를 측정하여 발열체로부터 $0^{\circ}C$까지의 거리인 유효발열거리를 확인하였다. 또한 열 중첩에 의한 CNT 간의 간격을 결정하기 위해 CNT를 150, 200, 300mm의 간격으로 삽입하여 총 4가지의 Case로 실내실험을 진행하였다. 실내실험과 함께 콘크리트 실험체의 열전도도 분석을 위한 수치해석을 수행하였다.

Keywords

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Fig. 1. Schematic drawing of CNT embedded into concrete slab

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Fig. 2. Laboratory test

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Fig. 3. Single installation of carbon nanotube

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Fig. 4. Dual installation of carbon nanotube of spacing of 15 cm

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Fig. 5. Dual installation of carbon nanotube of spacing of 20 cm

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Fig. 6. Dual installation of carbon nanotube of spacing of 30 cm

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Fig. 7. Element mesh and boundary conditions for the simulations

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Fig. 8. Results of simulation

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Fig. 9. Results of numerical analysis

Table 1. Concrete pavement mix proportioning

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Table 2. Physical properties of concrete

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