Characteristics:
Typically have a relatively simple structure and lower cost.
Commonly found in industrial plants, warehouses, and similar locations.
Noise sources are mainly concentrated in the motor, fan blades, and vibration of the casing.
Noise Reduction Methods:
Vibration Isolation:
Focus on vibration isolation of the motor and casing. Use rubber vibration damping pads or spring isolators to isolate the rigid connection between the motor and casing and the supporting structure.
Ensure flexible connections are used where the fan connects to the wall or roof to reduce vibration transmission.
Fan Blade Optimization:
Replace with low-noise fan blades, which typically use optimized aerodynamic profiles to reduce air turbulence.
Casing Soundproofing:
Attach sound-absorbing materials (such as sound-absorbing cotton or soundproofing felt) inside the casing to reduce casing resonance and noise radiation.
Duct Design:
Optimize duct design to reduce air resistance and turbulence, thereby reducing wind noise.
Add sound-absorbing materials to the inner walls of the duct.
Installation Location:
Install in a location as far away as possible from areas that require quiet.
2. Fiberglass Bell-Mouth Negative Pressure Fans:
Characteristics:
The bell-mouth design helps improve airflow and reduce air resistance.
Fiberglass material has good corrosion resistance and some sound absorption properties.
Commonly used in locations with higher noise requirements, such as livestock farms and greenhouses.
Noise Reduction Methods:
Material Advantages:
Fiberglass itself has a certain sound absorption effect. Take advantage of this feature by adding sound-absorbing coatings or materials to the inner wall of the casing.
Bell-Mouth Structure Optimization:
Optimize the design of the bell-mouth structure to reduce wind noise. For example, add guide vanes to the inside of the bell-mouth to reduce air separation and turbulence.
Belt Drive Noise Reduction (for Belt-Driven Models):
Regularly check and adjust the belt tension to avoid noise caused by loose or overtight belts.
Replace with low-noise belts.
Motor Vibration Isolation:
Similar to galvanized steel fans, use vibration damping pads or isolators to isolate motor vibration.
Duct Treatment:
Add sound-absorbing materials to the inner walls of the duct to reduce noise transmission.
Remote Installation:
If conditions permit, the fan can be installed in a location far from areas that require quiet, using distance to reduce the impact of noise.
