Using Patterned Surface Wettability for Improved Frosting/Defrosting Performance (OR-16-C032)

The goal of this project was to assess the potential benefits of using a highly-controlled surface wettability to preferentially condense (and therefore locate) water droplets on a heat transfer surface during the early stages of frost growth to affect the thermophysical properties of the frost layer (i.e. density, thermal conductivity, etc.). It was postulated that a thinner, denser frost layer might lead to improved heat conduction (and therefore improved air-side heat tranfer) and longer operational periods before defrosting becomes necessary. The retention of less water on the heat transfer surface following defrosting might also be used to slow frost growth in the subsequent cycle and therefore lengthen the operational cycle. Thus, accompanying this objective was the goal of creating heat transfer surfaces that more completely drain the melted frost layer during an applied defrost cycle.