Collision of water droplets with different initial temperatures

The experimental research into water droplet collisions resulting in their secondary atomization has been performed. The temperature of the first and second droplets was 20°С and 90°С, respectively. The interaction regime maps using the dimensionless linear collision parameter and the Weber number have been plotted. We also determined the integral characteristics of child droplets: size and number. When droplets with a temperature of 90°С were used, the critical Weber numbers went down by 10–30% for disruption, 5–15% for separation, and 15–35% for coalescence. For bounce, they increased by 50–80%. The number of newly formed child droplets for droplets with a temperature of 90°С increased by 5–20% relative to the droplets with a temperature of 20°С. The integral characteristics of child droplets and interaction regime maps of droplets with different temperatures can be used to optimize heat and mass transfer technologies.