What Causes Fogging on the Outside of Car Windows in Summer Rainy Days?

[LilaDella]

The significant temperature difference between the inside and outside causes water vapor to condense on the windshield, forming fog. Below is an introduction to how car defogging works: 1. The physical principle of car cold air: After the liquid refrigerant absorbs heat from the cooled object in the evaporator, it vaporizes into low-temperature, low-pressure steam, which is then sucked into the compressor, compressed into high-temperature, high-pressure steam, and discharged into the condenser. 2. The physical principle of hot air defogging: When gas containing fog flows through the defogger at a certain speed, due to the inertia of the gas, the droplets formed by the collision of fog with the wave plates are large enough that the gravity of the droplets exceeds the combined force of the gas lift and the surface tension of the liquid, causing the droplets to separate from the surface of the wave plates.