Study of thermal conductivity of ice clusters after impact deposition on the silica surfaces using the ReaxFF reactive force field

• Published in: Physical chemistry chemical physics : PCCP 2016-01, Vol.18 (3), p.1587-1594
• Main Authors: Rahnamoun, A, van Duin, A. C. T
• Format: Article
• Language: English
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c5cp05741h

During aircraft or spacecraft missions, ice accumulates on different parts of their surface elements. An important parameter affecting the ability to remove this ice from the surface is the heat transfer characteristics of the accumulated ice. The ice heat transfer is related to the process of ice formation and its density and internal structure. In this study we investigate the effects of the ice and silica structure and the ice cluster attachment mechanism to the silica surface on the thermal conductivity (TC) of the attached ice cluster using the ReaxFF reactive force field. The purpose of this study is to investigate the thermal transport in amorphous and crystalline ice after high-velocity deposition on the silica surfaces. A dual thermostat method has been applied for the calculation of TC values. The validity of this method has been verified by comparing the calculated values of TC for crystal and amorphous ice with available experimental values. Our calculations show that the TC values of both crystal and amorphous ice drop after deposition on the silica surfaces. This decrease in the TC is more significant for the ice deposition on suboxide silica surfaces. Furthermore, crystal ice shows higher TC values than amorphous ice after accumulation. However, when crystal ice impacts on the silica surface at 1 km s −1 impact speed, the crystalline shape of the ice cluster is lost to a considerable level and the TC values obtained for the ice clusters in such cases are closer to amorphous ice TC values. We observed a decrease in the TC values when ionic species are added inside the ice clusters. During aircraft or spacecraft missions, ice accumulates on different parts of their surface elements.