Study on methods of measuring frost crystal dimensions/structure and frost scraping force using a scanning probe microscope

Frosting on a cooling surface causes serious damage as well as economic losses. Therefore, it is necessary to clarify the mechanism of frosting on a cooling surface both scientifically and technologically. In addition, taking the size of frost crystals into account requires nano-micro-scale investigation. However, there have been few such studies. Thus, the focus of the present study is methods of measuring frost crystal dimensions/structure and frost scraping force in nano-micro-scale fields. In the present study, methods by which to measure frost crystal dimensions/structure, such as diameter, height, number of frost crystals, and interval between adjoining frost crystals, as well as the force required to scrape frost from a cooling surface using a scanning probe microscope (SPM) are proposed, and the effectiveness of these methods is investigated. With the exception of the frost crystal height, the feasibility of these measurements was demonstrated, and examples of the correlation of frost dimensions/structure and frost scraping force could are presented.