Semnan University Press Journal of Heat and Mass Transfer Research 2345-508X 2 1 2015 04 01 Investigation of purge time in cathodic dead-end mode PEMFC 13 19 335 10.22075/jhmtr.2015.335 EN Amirmohammad Khazaee Pool School of Mechanical Engineering, Babol Noshirvani University of Technology, Iran Rouzbeh Shafaghat School of Mechanical Engineering, Babol Noshirvani University of Technology, Iran Qadir Esmaili School of Mechanical Engineering, Amol Islamic Azad University, Iran Abbas Ramiar School of Mechanical Engineering, Amol Islamic Azad University, Iran Journal Article 2013 10 11 Recently, special type of fuel cells has been developed that operates in a Dead End mode. Working in this condition, the Dead-End fuel cell is supplied with hydrogen almost at the same rate of consumption. It is noteworthy to mention that all of the water transport mechanisms have been considered in this simulation. Water accumulation that is directly proportional to the cell current is of a great importance and has a negative impact on the cell voltage and its performance. Hence, water and gas management in Dead-End mode should be handled properly. To do so, determining the suitable time of purge and its duration is valuable with a direct impact on cell performance. In this paper, the channel and gas diffusion layer have been considered as a single control volume and the blockage effect has been investigated by means of thermodynamic analysis. In order to obtain a reasonable assumption, we have studied three different scenarios: GDL flooding, channel flooding and GDL-channel flooding simultaneously. The influence of blockage effect rate of gas diffusion layer and channel on cell voltage drop, performance and purge time have been studied. Voltage drop curves in different operating conditions have been presented and the results show an acceptable agreement with experimental studies. These curves have been investigated for different current densities (0.5, 1 and 1.5 A/cm2), active areas (25, 50 and 100 cm2) and temperatures (60-80 °C).An Increase in temperature and in current density, reduces purge time interval, while increasing active area has an inverse impact. In high current densities, the effect of temperature variation can be neglected.

https://jhmtr.semnan.ac.ir/article_335_f9b902fc3289af4dd08de5d1de54f68f.pdf