OPTICAL MEASUREMENTS OF ICE ADHESION
The adhesion of ice onto surfaces (metals, elastomers, etc.) has been primarily measured through destructive mechanical stress-strain testing. These measurements are error prone, imprecise, and difficult to reproduce, making investigations of new icephobic surfaces challenging. Additionally, mechanical ice adhesion testing methods cannot be easily translated into on-the-ground and in-flight ice formation detection. Our recent work suggests that non-destructive optical methods, such as Raman spectroscopy, may be an excellent solution for rapid, reproducible, and accurate measurements of ice adhesion strength at different temperatures, across a range of formation conditions, and for different types of surfaces. These novel measurement techniques can also be incorporated on flight control surfaces, making them useful diagnostics for ice formation. Using these optical methods, we plan to develop new icephobic materials (carbonaceous, polymeric, and elastomeric materials) for mitigating ice formation.
Figure 1: Arduino-controlled thermo-electric cooler can maintain a wide range of temperatures for extended periods of time. The ice temperature is barely changed when an optical excitation of 2 mW is used.
Figure 2: Ice-adhesion measurement setup. Several elements of this system are currently operational, but we are still working on acquiring/designing/building other parts.