방사선 열화가 안전등급 케이블 화재에 미치는 영향 = Effect of Radiation Deterioration on Class 1E Cable Fire

다국어 초록 (Multilingual Abstract)

In this study, the effect of radiation deterioration on cable fire for a type of class 1E cable for a nuclear power plantwas investigated. Combustion and smoke characteristics were compared via a cone calorimeter test (ISO 5660-1), and thetoxicity index of the toxic gas emitted during combustion was analyzed by following the NES 713 standard. The peak heatrelease rate of the irradiated cable was measured to be approximately 38 kW/m2 higher than that of the non-irradiated cable. Additionally, the heat release rate of the irradiated cable temporarily increased during a certain period. This can be ascribedto the continuous pyrolysis and heat penetration as a result of the unstable formation of the char layer. The total heat releaseof the irradiated cable was measured to be approximately 2.2 times higher than that of the non-irradiated cable. Acorresponding increase of ~2.8% in the total mass loss was observed. In the case of smoke characteristics, the irradiatedcable was measured to be 2.3 times higher in the smoke parameter and 3.8 times higher in the smoke factor comparedto the non-irradiated cable. For the toxicity index, only CO was detected above the critical factor in the non-irradiated cable,whereas both CO and HBr were detected above their critical factors in the irradiated cable.

국문 초록 (Abstract)

본 연구에서는 원자력 발전소에서 사용되는 안전등급 케이블 1종에 대해 방사선 열화가 케이블 화재에 미치는 영향에 대하여 조사하였다. 콘 칼로리미터 시험(ISO 5660-1)을 통한 연소특성 및 연기특성을 비교하였고 NES 713 규격에따라 연소 시 방출되는 독성가스에 대한 독성지수를 분석하였다. 방사선 조사 케이블의 최대 열방출률이 비방사선 조사케이블보다 약 38 kW/m2 높게 측정되었으며 비방사선 조사 케이블과는 다르게 다르게 일부 시간대에서 일시적으로열방출률이 증가하였다. 이는 char층의 불안정한 형성이 지속적인 열 침투 및 열분해를 일으킨 것으로 판단된다. 방사선 조사 케이블의 총 열방출률은 비방사선 조사 케이블에 비해 약 2.2배 높게 측정되었으며, 그에 따른 총 질량감소는 약 2.8% 증가하였다. 연기특성의 경우, Smoke parameter는 방사선 조사 케이블이 약 2.3배 높은 값이 측정되었으며, Smoke factor의 경우 방사선 조사 케이블이 약 3.8배 높게 측정되었다. 독성지수의 경우 비방사선 조사 케이블은CO만 치사농도 이상으로 측정되었으나, IR 케이블에서는 CO뿐만 아니라 HBr도 치사농도 이상으로 검출되었다.

목차 (Table of Contents)

• 1. 서 론 2. 시험재료 및 방법 3. 시험결과 4. 결 론 후 기 References

참고문헌 (Reference)

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