This study conducted a numerical investigation into how air inlet temperature and relative humidity impact the performance of a polymer electrolyte membrane fuel cell (PEMFC) system specifically designed for compact firefighting special trucks. A PEMFC stack model was created using Simcenter AMESim, analyzing the characteristics of cell voltage, stack power, and heat generation across air inlet temperatures from 50 to 90 ℃ and relative humidities ranging from 30 to 100%. The results showed that cell voltage and stack power varied nonlinearly with air inlet temperature and relative humidity, exhibiting greater temperature sensitivity under high-humidity conditions. In the high-temperature and high-humidity region, voltage and power tended to decrease, possibly due to reduced oxygen partial pressure and water accumulation. Relatively high stack performance was achieved at 70–80 °C and 50–70% RH, indicating that both parameters should be considered simultaneously when optimizing operating conditions. These results highlight the strong interaction between air inlet temperature and relative humidity as critical operating parameters that influence PEMFC performance, emphasizing the need to consider both factors simultaneously for optimizing operating conditions.

Abstract
1. 서 론
2. 연료전지 시스템 모델
    2.1 시스템 구성 및 해석 조건
    2.2 지배방정식
3. 결과 및 고찰
    3.1 공기 입구 온도 및 상대습도 변화에 따른 셀전압 분석
    3.2 스택 전압 분석
    3.3 스택 출력 분석
4. 결 론
후 기
References

• 박다인(Ph, D. Student, Dept. of Mechanical Engineering, Wonkwang University) | Da In Bak
• 김경빈(Undergraduate Student, Dept. of Mechanical Engineering, Wonkwang University) | Kyung Bin Kim
• 이상호(Dept. of Mechanical Engineering, Innovation Center for Engineering Education, Wonkwang University) | Sang Ho Lee Corresponding author
• 김영렬(Jinwoo SMC Co., LTD., R&D Institute, Director, Doctor of Engineering) | Young Ryul Kim