How do range hood fans work?

In fact, the working principle of a range hood is mainly based on aerodynamics and centrifugal force, completing the collection, separation, and exhaust of cooking fumes through the following two key steps:

Negative Pressure Suction

After the power is turned on, the motor drives the impeller to rotate at high speed. The impeller blades of the range hood are specially designed to push air towards the exhaust pipe, creating extra space on the side of the stove, "sucking" away the air and creating a negative pressure zone inside the range hood. According to the aerodynamic principle that "fluids flow from high-pressure areas to low-pressure areas," the cooking fumes above the stove are attracted by the negative pressure, forming an upward airflow, and the fumes, steam, and harmful gases are then drawn into the range hood. This process also conforms to Bernoulli's principle, that is, the faster the airflow, the lower the air pressure, thus creating a pressure difference that draws in the cooking fumes.

Fume Separation

The sucked-in cooking fumes first pass through an oil filter, which intercepts some large oil droplets and impurities, completing the first stage of fume separation. Subsequently, the fumes enter the air duct, where the high-speed rotating impeller causes the oil mist to condense into oil droplets under centrifugal force. These oil droplets are thrown onto the inner wall or oil mesh, and eventually flow into the oil collection cup through the oil passage, while the purified air continues to flow and is discharged outdoors or into the public flue through the exhaust pipe.