Numerical investigation of condensation characteristics of a moist air-to-air plate-fin heat exchanger and experimental validation

•Numerical investigation of condensation characteristics is carried out.•The change of mcond can be divided into three stages as t mdry, increases.•The surplus potential of condensation (δ) is proposed and it is more affected by cooling air side.•Some operation strategies were proposed for the dehumidification under high temperature and high humidity.