Using the principles of fluid mechanics, compressed air is used as the driving force to generate negative pressure and direct water out of the nozzle. The cavitation effect is utilized to efficiently atomize the secondary impact water into ultrafine dry mist particles below 0.5 μ m. The special nozzle structure results in a fan-shaped distribution. Spraying dry mist particles into the air will completely vaporize, achieving the purpose of adjusting humidity.