Luoyang CNBM Air Grille Fan Room Noise Reduction Case Study

Project Overview

This industrial fan room noise reduction project was completed for CNBM in Luoyang. Multiple large centrifugal air grille fans run continuously in the factory workshop, producing strong aerodynamic noise, airflow regenerated noise and mechanical radiation noise. Severe indoor sound reverberation leads to excessive noise at workshop operation posts and factory boundaries.

We delivered a full fan room acoustic enclosure solution, including modular sound insulation panel assembly, large-area acoustic louver installation, internal sound absorption treatment and vibration isolation construction. The project achieves compliant noise control while fully guaranteeing fan ventilation, heat dissipation and daily equipment maintenance.

Noise Sources

Main noise sources of the air grille fan room:

• Centrifugal fan aerodynamic rotational noise (dominant medium and high frequency noise)

• Airflow impact and regenerated noise from air grille ventilation system

• Fan casing radiation noise and motor operating noise

Custom Fan Room Noise Reduction Solution

Modular Acoustic Enclosure Wall

Heavy-duty composite sound insulation sandwich panels are adopted to build a fully enclosed fan room enclosure. The integrated structure suppresses indoor noise reverberation and outward noise transmission. All panel joints are fully sealed to avoid sound leakage, and acoustic observation windows are reserved for real-time equipment operation inspection.

Large-Area Acoustic Louver Ventilation System

Custom large-size ventilation acoustic louvers are installed on the enclosure wall as the main air intake channel. The louver structure allows smooth fresh air circulation to meet fan heat dissipation demands, while effectively blocking internal noise from leaking outward. Matching exhaust silencers are equipped to eliminate airflow secondary noise.

Indoor Sound Absorption & Vibration Isolation

High-density sound-absorbing materials are laid on the inner wall and top of the enclosure to reduce indoor noise superposition and reverberation. Fan bases are equipped with spring vibration isolators, and pipeline flexible connectors and vibration-damping hangers are installed to cut off structural-borne noise transmission.

Key Specifications

• Noise reduction performance: 18–24dB(A), meeting industrial workshop and factory boundary noise standards

• Ventilation guarantee: Zero impact on fan air volume, air pressure and heat dissipation efficiency

• Industrial durability: Sealed and dust-proof structure, suitable for long-term factory operation

• Maintenance accessibility: Reserved overhaul space and passages for equipment hoisting and repair

On-Site Installation

The modular fan room acoustic enclosure is integrally assembled on site around the air grille fan units. The matching acoustic louver wall forms a professional ventilation and noise reduction system. The overall structure is stable and neat, with all sealing and vibration reduction processes completed to ensure no noise leakage and stable equipment operation.

Project Results

• Qualified noise control: The industrial acoustic enclosure effectively reduces fan room radiation noise, solving workshop and factory boundary noise exceeding problems.

• Stable production operation: Scientific ventilation design ensures continuous and efficient operation of air grille fan units without overheating failure.

• Durable performance: Industrial-grade anti-sealing and vibration-damping structure adapts to long-term continuous industrial operation.

• Convenient daily maintenance: Reserved overhaul passages support fast equipment inspection, replacement and hoisting work.