Fan noise reduction

Main Noise Sources:

From the mechanism and characteristics of fan noise, it mainly consists of four parts: aerodynamic noise from the air inlet and outlet; electromagnetic noise from the motor; solid-borne noise radiated through the foundation due to fan vibration; and mechanical noise radiated by the casing, pipelines, motor bearings, etc.

Among these four parts, the aerodynamic noise from the inlet and outlet is generally the strongest. According to actual measurements and analysis of fans, the aerodynamic noise of a fan is approximately 12–25 dB(A) higher than the noise from other parts. Therefore, when implementing noise control measures for fans, aerodynamic noise should be the primary consideration.

Noise Reduction Measures:

1. Acoustic Enclosure

Install an acoustic enclosure for the fan, equipped with inlet and outlet silencers, without affecting the fan’s ventilation and heat dissipation. The acoustic enclosure is detachable and includes an acoustic door and observation window for inspection and maintenance.

The acoustic enclosure is suitable for situations where a significant noise reduction of about 20–30 dB(A) is required.

2. Acoustic Wrapping for Inlet Ducts

Apply acoustic wrapping to the inlet ducts, with a structure consisting of a damping layer, low-frequency sound insulation layer, sound absorption layer, and steel plate protective surface layer.

3. Silencer for Exhaust Ducts

Install a silencer in the exhaust duct to effectively reduce the aerodynamic noise of the equipment and the regenerated noise caused by high-speed airflow.

4. Vibration Damping Design for Casing and Foundation

Add vibration damping methods such as damping spring isolators, rubber isolators, cork, or asphalt felt between the fan casing and the foundation to reduce noise transmission.

Project Features:

Ø Tailored noise reduction measures are selected based on specific noise control requirements.

Ø The noise reduction measures feature a rational structure and excellent noise reduction effects, meeting national acceptance standards.

Ø After implementation, the normal operation, maintenance, and inspection of the original equipment are largely unaffected.

Ø The newly added measures are aesthetically pleasing, robust, and have a service life of up to 15 years.