Experimental study of water drop impact on wood surfaces

Experiments of water drop impact on wood surfaces were performed. The initial drop diameter was fixed at 2.4 mm ± 0.1 mm, while the drop impact Weber numbers were varied from 42 to 258. Three kinds of wood, such as Paulownia, Fraxinus mandshurica and Jatoba were considered, since they are combustible materials and popularly used for timber flooring, office furniture, etc. in China. In addition, they have different basic density, surface properties and water absorbability. The experimental results show that the critical impact Weber number of droplet splashing decreases as basic density of the wood increases. The spread factor is affected by wood surface properties and its basic density. It was also found that the water drop spreads along the direction of the grooves after it impacts on wood surface which phenomenon depends on pore grooves of wood surface.