Experimental study on single droplet impinging on a heated and inclined wall at early impaction stage

Droplet-wall impaction exists in many nuclear installations and severe accidents. In this study, we experimentally investigate a single droplet impinging on a heated and inclined wall at the early impaction stage. Especially, the droplet spreading behavior is analyzed by changing the wall temperature (T-w = 40 degrees C to 262 degrees C), the droplet Weber number (We(d) = 0.66 to 589), the droplet Reynolds number (Re-d = 189 to 14,046) and the wall inclined angle (alpha = 0 degrees to 45.6 degrees). The results show that the increase of We(d) and Re-d is beneficial to the droplet spreading, but not to the shrinking. The droplet front and back spread factors are quite different due to the gravity. Further, the maximum spread factor (beta(max)) with T-w at different We(d) is obtained and analyzed. These findings are helpful to fundamentally understand the droplet spreading on the heated and inclined wall at the early impaction stage. (C) 2020 Elsevier Ltd. All rights reserved.