Comparison of single droplet impact behaviors on the burning shallow/deep pool

Dynamics of single water droplet impinging on burning heptane surface were investigated experimentally in shallow/deep pool. The pool regimes were newly defined and a translation region was found in burning pools. At low Weber numbers, the crater-jet only occurs for shallow pools while the crater-secondary jet does for deep pools. The bubble was observed at high Weber numbers for both pools. Compared to Weber number, liquid depth has a significant effect on the number of jet (jet and secondary jet). Some characteristic parameters, such as maximum crater depth, width and jet height were analyzed as a function of impacted dimensionless depth (1.9-11.1) and Weber numbers (246-638). Maximum crater depth and width are mainly determined by liquid depth in shallow pools, while they significantly depend on Weber number and impact behavior in deep pools. Maximum jet height is highly related to liquid depth and temperature. Additionally, the damping effect of fire plume on droplet impact velocity was explored and theoretical correlation between droplet impact velocity and impact height was proposed. (C) 2018 Elsevier Masson SAS. All rights reserved.