Effect of Anti-Icing Chemicals during Hoar Frost Situations

Abstract

Anti-icing chemicals are used during hoar frost situations to avoid slippery road conditions. During hoar frost situations, humidity is transported from the air to the road surface. This leads to continuous dilution of the applied solution, until it eventually freezes. The protection time for a certain anti-icing application during hoar frost situations is therefore limited, and depends both on the dilution process and the freezing process. In this work, a laboratory setup has been used to study the effect of three commonly used chemicals, with different hygroscopic properties on the dilution process. An increased mass transfer rate up to 30% was seen for all chemicals in the start of the dilution process. The effect quickly diminished and after only 60 min it returned to a similar rate as without any chemical present.