For heat exchangers operating with low air temperature and high humidity

frost appears on the fin surfaces

which increases the thermal resistance and blocks the air channels. Frosting process on a wavy plate was experimentally investigated. This study focuses on several factors affecting the condensate water droplets freezing process and frost layer growth process

i.e. the cooling surface temperature

the air velocity and the plate structure. The results show that the condensate droplets are smaller and freeze earlier with lower cooling surface temperature. The frost layer grows faster with lower cooling surface temperature and higher air velocity. Compared with flat plates

frost height growth on wavy plates is much slower.