Why do candles burn and drip into round pancakes?

I don’t know if you have noticed when you are eating cakes, when the wax oil dripping from the burning candles falls on the surface of the cake, it will solidify into a round pancake. Why does wax oil always solidify into a round shape? In fact, the principle is this

In the burning process of the candle, the function of the wick is very important. Only the wax oil transmitted to the vicinity of the flame under the capillary action of the wick will have enough temperature to vaporize and react with oxygen to burn. A little further away from the flame, there is still enough temperature to melt the wax, which will cause the candle to keep dripping with liquid wax as it burns.

When liquid wax comes into contact with a solid surface, it solidifies rapidly, resulting in round wax spots. However, when the wax drops into the water, because the thermal conductivity of the water is not as high as that of most solids, the wax drop solidifies slowly, so it will first be impacted by the water surface to produce different motions and change its own shape. completely solidified. As the falling kinetic energy increases, the wax droplets splash into the water at a larger and larger distance, forming a change from small balls to leaves, to small bowls, to unfolded petals and broken patterns.

Since the thermal conductivity effect is proportional to the temperature difference, the wax droplet solidifies at a slower rate when using warm water for the experiment, so more reflection tracks are preserved, and the structure of the solidified "florets" is more abundant.