Fig 1.
Project location of CBD 500kV.
Table 1.
Environmental noise emission standard of industrial enterprises (GB12348−2008).
Fig 2.
Noise spectrum of different transformer models (provided by State Grid Corporation).
Table 2.
Sound power level of the axial fans.
Table 3.
Transformers’ noise path.
Table 4.
Transformers’ noise path.
Fig 3.
Geometry model of the project.
Fig 4.
Geometry model of the rooms.
Fig 5.
Diffraction of sound barrier [6].
Table 5.
SPL (10m)and sound power level of a truck mixer and pump.
Fig 6.
The noise map-without barriers.
Fig 7.
The noise map-with barriers.
Table 6.
The noise at sensitive control points with/without barriers.
Table 7.
Sound attenuators reduction.
Table 8.
The noise attenuation with sound attenuators (dampers).
Fig 8.
Sound dampers improvement.
Fig 9.
Acoustic damper optimization.
Table 9.
Absorption coefficient of mineral wool panels.
Fig 10.
Absorption improvement.
Table 10.
The noise at sensitive control points with/without mineral wool panels.
Table 11.
Enclosure wall- sound reduction.
Table 12.
The noise attenuation with aerated concrete blocks wall.
Fig 11.
Enclosure wall improvement.
Table 13.
Comparison results of noise reduction performance and time complexity of methods in different environments.