Heat Transfer on a Vertical Plate in Steam Pulse Jets under Dropwise Condensation

Abstract

The development of an effective heat exchanger in the dropwise condensation is hoped for the saving of resource. However, the heat transfer characteristic is influenced by a lot of factors, and the relation has not been clarified yet. In this research, the heat transfer characteristic under the vibration of the pulse jet steam has been experimentally investigated from the cooperative effect of the cleaning and covering actions with the falling drops by the vibration of the pulse jet steam. As a result, the pulse jet grew the heat transfer coefficient than a continuous jet and the increase rate has often grown within the ranges of the number of low frequencies of pulse jets. Moreover, an empirical formula concerning the amount of the vapour flow and the heat transfer coefficient in each jet condition was obtained.