Noise and vibration generated during fan operation not only affect workplace comfort but can also accelerate equipment fatigue and failure. This article systematically introduces the mechanisms of aerodynamic noise and mechanical vibration, reviews noise reduction and vibration damping technologies such as silencers, sound barriers, elastic mounts, and dynamic balancing, and offers practical implementation suggestions based on typical application cases to help you build a quiet and efficient ventilation system.
1. Hazards and Sources of Noise & Vibration
Impact: Long-term exposure to high noise can cause hearing loss and increased psychological stress; persistent vibration can loosen foundations, fatigue bearings, and lead to coupling failure.
Noise Sources:
Aerodynamic noise: Turbulence and impact sounds between impeller and guide vanes
Mechanical noise: Operation noise from motors, bearings, and couplings
Vibration Sources:
Poor dynamic balance, shaft misalignment
Inadequate foundation stiffness or loose support bolts
2. Fan Noise Control Technologies
Silencers & Mufflers:
Baffle silencers (10–20 dB reduction), enclosure silencers (15–25 dB reduction)
Sound Barriers & Rooms:
Sound-insulating walls near the source or receiver (recommended thickness ≥50 mm, with perforated surface absorption layers)
Aerodynamic Optimization:
CFD-optimized blade curvature and guide vane spacing to reduce turbulence; energy-dissipating elements at inlets/outlets to smooth airflow
3. Fan Vibration Damping Technologies
Dynamic Balancing & Shaft Alignment:
Impellers should be balanced to G2.5 grade; laser or jack alignment to keep shaft error ≤0.05 mm
Elastic Mounts & Vibration Isolators:
Spring or rubber isolators to dampen foundation transmission; select based on unit weight and frequency
Foundation Reinforcement:
Use concrete bedding and prestressed bolts to increase natural frequency; reinforce critical points to avoid resonance
4. Typical Applications
Chemical plant supply fan:
Problem: Outlet noise at 95 dB(A)
Solution: Install baffle silencer and rubber vibration pads, reduce noise to 75 dB(A), vibration amplitude drops by 60%
Tunnel ventilation main unit:
Problem: Poor balance leads to high bearing temperature
Solution: Rebalance, install spring mounts, bearing temperature drops by 15%, vibration within limits
5. Implementation Advice
Comprehensive assessment in the design phase with airflow simulation and structural vibration analysis
Prioritize aerodynamic/source optimization, followed by silencing and vibration isolation
Deploy sound and vibration sensors for monitoring and early warning
Regularly retest balance and isolator status, and clean silencers every six months
By applying these combined technical measures, you can achieve comprehensive fan noise and vibration control, ensuring a quiet, safe environment for production and research.