Sound absorption and noise reduction plate special for cooling tower noise reduction and anti-freezing device

Abstract

The invention provides a special noise absorbing plate for a noise reducing and antifreezing device of a cooling tower. The special noise absorbing plate comprises a supporting frame, a small circular wind guider, a porous plate, a piece of waterproof non-woven fabric and sound-absorbing cotton, wherein, the porous plate wraps the left and the right sides and the end face of the supporting frame; the sound-absorbing cotton is filled in the supporting frame; the cross section of the noise absorbing plate is in a bullet-shaped; as the exterior end of the noise absorbing plate is formed through butting the small circular wind guider with a trapezoidal sound-absorbing segment, under the conditions of the same spacing, the cross section of an air inlet between two noise absorbing plates is enlarged, therefore, the suction of air is easier, and the speed of air suction is increased; as the end face at the tail part is designed into a noise-absorbing structure, the size of effective noise absorption of the noise absorbing plate is enlarged, and the effect of noise absorption is improved; according to tests under the same experimental conditions, the noise reducing effect is improved by 10 to 15 percent.

Description

Technical field: [0001] The invention relates to an external noise reduction device of a cooling tower in a power plant, in particular to a sound-absorbing and noise-reducing board in the external noise reduction device of a cooling tower. Background technique: [0002] With the continuous improvement of national environmental protection requirements, the country has put forward more stringent requirements for noise reduction of cooling towers in power plants. The noise at the boundary of power plants must comply with the Class III standard in GB12348-90, and the environmental noise in GB3096-93. Class 3 standards, that is, daytime ≤ 65 decibels, night ≤ 55 decibels. According to this requirement, after the cooling tower undergoes noise reduction treatment, the noise reduction rate must be ≥ 25 decibels. For this reason, we had to give up the original water falling noise reduction device inside the tower. At the end of 2006, we and the Northeast Electric Power Design Instit...

AI Technical Summary

Problems solved by technology

After actual research, the noise reduction devices built in the three cooling towers in Sichuan Jialing Electric Power Co., Ltd. are the same as the technical solutions disclosed in the patent No. 200720108361.3 "Noise reduction and diversion devices for large natural ventilation cooling towers". Both ends of the noise-eliminating guide vanes are semicircular, and only two sides are sound-absorbing surfaces. The effective sound-absorbing area of ​​the noise-eliminating guide vanes is small, and all the noise-eliminating guide vanes are fixed vertically on the facade frame. The distance between two adjacent noise-eliminating guide vanes is fixed, and the structure of the semicircular air guide head not only affects the smooth entry of cooling and ventilation, but also the noise waves in the noise source are directly transmitted outward through the gap between the two noise-eliminating guide vanes, without passing through The repeated refraction and attenuation of the noise-eliminating deflectors not only fails to achieve the noise-reducing effect mentioned in the 200720108361.3 manual, but also cannot be adjusted; since the gap between the noise-eliminating deflectors cannot be adjusted, the progress of the cooling tower The tuyere is always connected with the outside world. When the outside temperature is too low, a high-speed cold air flow will be formed at the air inlet of the cooling tower, which will naturally cause serious ice-hanging phenomenon, especially in the north.

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