Effect of variable parameters on delayed droplet icing process in proton exchange membrane fuel cell flow channel

Modifying the characteristics of the flow channel is essential to retard or prevent icing and improve the low-temperature operational performance of proton exchange membrane fuel cells (PEMFCs). This paper presents a two-dimensional transient mathematical model that investigates the influences of surface temperature, wettability, and volume size on the droplet icing process. The findings suggest that raising the surface temperature of the flow channel results in a longer droplet freezing time. Raising the surface temperature from 248.15 to 268.15 K can delay droplet freezing time by up to 62%. Increasing the surface contact angle from 78 to 150° can delay droplet freezing time by 45%. An increase in droplet volume can also prolong the time required for droplet freezing. Increasing the droplet volume size from 1 to 4 μL can delay the droplet freezing time by 35%. Moreover, the optimal parameters for maximizing the duration of droplet freezing are identified using response surface methodology. The corresponding conditions are found to be a surface temperature of 267.96 K, a surface contact angle of 134.08°, and a droplet volume of 3.29 μL. This work offers valuable guidance for enhancing the low-temperature performance of PEMFCs through flow channel design optimization.