Experimental study on surface wave propagating through a grease–pancake ice mixture

A laboratory experiment was carried out in two wave tanks in a cold room. This experiment was designed to better understand the dispersion relation and amplitude attenuation for surface waves propagating through ice covers consisting of a grease and pancake ice mixture. Each test started from a calm condition to avoid reflection effects. The portion of the wave signals before the arrival of reflections was used to measure the wave number and the attenuation rate. The comparison between experimental results and the two-layer viscous model (Keller, 1998) indicates that modeling a grease–pancake ice cover as a viscous fluid is not sufficient to describe the observed dispersion relation and amplitude attenuation. Extended models including other mechanisms may be necessary to better describe wave–ice interactions for a grease–pancake mixture.