Longhong Electromechanical explains noise treatment methods for diesel generator sets. Details are as follows:

During operation, diesel generator sets typically generate noise levels of 95–110 dB, which can cause significant harm 

to the surrounding environment. When noise reduction at the source is not feasible, 

what measures can be taken to control the noise from diesel generator sets?  

I. Analysis of Noise Sources in Diesel Generator Sets

   The noise from diesel generator sets is a complex combination of multiple sound sources. 

   Based on the mode of radiation, it can be categorized into aerodynamic noise, surface-radiated noise, and electromagnetic noise. 

   According to the cause of generation, surface-radiated noise can further be divided into combustion noise and mechanical noise. 

   Among these, aerodynamic noise is the primary noise source in diesel generator sets.  

1. **Aerodynamic noise** is generated by the unstable flow of gases, i.e., disturbances in the gas and the interaction between gas and objects. 

       Aerodynamic noise directly radiated into the atmosphere includes intake noise, exhaust noise, and cooling fan noise.  

2. **Electromagnetic noise** is produced by the high-speed rotation of the generator rotor within an electromagnetic field.  

3. **Combustion noise and mechanical noise** are difficult to strictly distinguish. Generally, noise radiated outward through the cylinder head, 

      piston, connecting rod, crankshaft, and engine block due to pressure fluctuations from combustion in the diesel engine cylinder is referred 

      to as combustion noise. Noise generated by piston impacts on the cylinder liner and mechanical impacts of moving parts is called mechanical noise. 

      In direct-injection diesel engines, combustion noise is usually higher than mechanical noise, whereas in non-direct-injection diesel engines, 

      mechanical noise tends to dominate. However, at low speeds, combustion noise generally exceeds mechanical noise.  

 II. Noise Control Measures for Diesel Generator Sets

Control Measure 1: "Soundproof Room"  

Install a soundproof room at the diesel generator set location, with dimensions of 8.0 m × 3.0 m × 3.5 m. 

The outer walls of the soundproof panels are made of 1.2 mm galvanized steel sheets, while the inner walls are 0.8 mm perforated panels. 

The middle layer is filled with 32 kg/m³ ultra-fine glass wool, and the grooves of the steel beams are also filled with glass wool.  

Control Measure 2: "Exhaust Air Noise Reduction"

Diesel generator sets rely on built-in fans for exhaust. Install an AES-type rectangular silencer at the front of the exhaust room, 

with dimensions of 1.2 m × 1.1 m × 0.9 m. The silencer contains sound-absorbing panels with a thickness of 200 mm and a spacing of 100 mm. 

The panels are constructed with perforated galvanized sheets on both sides, sandwiching ultra-fine glass wool. Nine identical silencers are 

assembled into a larger silencer measuring 1.2 m × 3.3 m × 2.7 m. An exhaust louver of the same dimensions is placed 300 mm in front of the silencer.  

Control Measure 3: "Intake Air Noise Reduction"

Install a natural intake silencer on the roof of the soundproof room. The silencer is constructed similarly to the exhaust silencer, 

with a net silencing length of 1.0 m and a cross-sectional size of 3.4 m × 2.0 m. The sound-absorbing panels are 200 mm thick with a spacing of 200 mm. 

The silencer is connected to an unlined 90° silencing elbow, which is 1.2 m long.  

Control Measure 4: "Exhaust Smoke Noise Reduction" 

Noise from exhaust smoke is reduced using two residential-type silencers provided by the diesel generator set manufacturer. 

After silencing, the exhaust smoke is combined into a single Φ450 mm pipe, which extends upward through the exhaust louver for discharge.  

The above content is compiled and published by the generator manufacturer—Guangdong Longhong Electromechanical Equipment Co., Ltd. 

For details, visit (https://www.longhongpower.com).