In this study, the heat transfer characteristics of a liquid hydrogen (LH2) tank with multilayer insulation (MLI) were numerically investigated. The temperature distribution inside the LH2 tank and within the MLI, as well as the temperature variation according to positional changes, heat transfer rate, and boil-off rate (BOR), were compared and analyzed. The results showed a distinct stepwise temperature drop in Case 4 with 20 MLI layers and Case 8 with 40 MLI layers, where the insulation thickness was greatest. Under the same number of layers, the temperature gradient became more gradual as the MLI thickness increased. In addition, the temperature variation in the tank head region indicated that increasing the number of MLI radiation layers reduced the radiative heat flux, resulting in a gentler temperature variation and a longer temperature drop range. Furthermore, the analysis of heat transfer and BOR showed that both rates decreased under the condition with the greatest MLI thickness and number of layers, demonstrating the best insulation performance. In particular, under the same 40-layer condition, the BOR value of Case 8 was more than three times lower than that of Case 5, indicating a significant improvement in thermal insulation efficiency.

Abstract
1. 서 론
2. 수치해석적 연구
    2.1 수치해석 대상 및 설계 조건
    2.2 지배방정식
3. 연구 결과 및 고찰
    3.1 액화수소 저장탱크 단면 온도 분포
    3.2 MLI 단열재 내부 온도 분포
    3.3 위치 변화에 따른 MLI 온도 변화 결과
    3.4 열전달률 및 증발률 비교 분석 결과
4. 결 론
References

• 임영찬(Dept. of Smart e-Automobile, Yeungnam University College) | Young Chan Lim Corresponding author