Why should oil be atomized prior to the oil combustion of oil-fired boilers?

The oil and air must be mixed for the combustion of the fuel droplets to take place. The combustion speed depends on the evaporation speed of oil droplets and the mixing speed of oil and air. The evaporation speed of oil droplets is related to the diameter and temperature of oil droplets. The smaller the fuel droplets, the higher the temperature and the faster the evaporation. On the other hand, it is conducive to mixing and combustion. The smaller the fuel droplets, the larger the air contract surface. Therefore, the fuel oil must be atomized before combustion. And, the oil can be heated and evaporated rapidly and fully burnt after it is injected to the furnace.