Analysis of Thermally Activated Sacrificial Micro Soft Layers for Reduced Surface–Ice Interface Strength

Abstract

The prompt removal of ice is crucial to the safe operation of maritime equipment. However, traditional deicing approaches such as steam jets or manual tools are costly in terms of energy consumption and human labor. If the ice interfacial strength can be reduced, the above problems can be much alleviated. Therefore, this paper introduces a new type of low-cost, thermally activated sacrificial soft layer that can change phase according to the user’s activation signal to reduce the surface–ice adhesion strength. The proposed gelatine soft layers, containing an environmentally friendly compound (CH3COOH or NaHCO3), are prepared in 50–70 mm2 films with a thickness between 0.5 mm and 0.8 mm at room temperature in around 1 h. Layers containing different chemical compounds are stacked vertically, which stay inert at room temperature or lower, but can be thermally activated to change from a solid to gas–liquid phase. The CO2 gas released from the chemical reaction is trapped between the surface–ice interface, greatly reducing the overall contact area, as well as the surface–ice adhesion strength. An experimental testbed was assembled in the lab, capable of measuring the interfacial ice adhesion strength according to the deflection of a polyurethane cantilever beam. The initial test results showed the promising properties of the layers, where no expansive equipment is required during the sample preparation, and the cost of raw materials to make a pair of soft layers is well below 0.1 USD/mm2. Under a −13 °C environment, the surface–ice adhesion strength of pure water ice was found to reduce by over 20%.