Dynamics Behaviors of Droplets Impacting on a Heated Tailings Surface

Tailings are produced by high-titanium blast furnace slag using "high-temperature carbonization-low-temperature chlorination" technology. In this paper, droplet impact on a heated tailings surface is experimentally investigated over a wide range of Weber numbers and surface temperatures. The spread of droplets into a liquid film on the tailings surface and dynamics behavior of the droplets were observed by a high-speed camera. Five regimes are observed, namely spreading, boiling induced break-up, advancing recoiling, splashing with continuous liquid film, and splashing with broken liquid film. In addition, the effects of Weber number and surface temperature on boiling mode and spread of droplets are examined. The scaling law of maximum spreading ratio with the Weber number is also established, and it agrees well with experimental measurements and the literatures over a range of Weber numbers and high temperature.