Fan silencer and noise reduction technology, fan noise control scheme to reduce fan noise

Fan noise control technology and fan noise reduction scheme, Shenzhen Quelte Sound and Noise Reduction Engineering Technology Co., Ltd. specializes in fan noise control and fan noise reduction, fan is widely used in industrial production enterprises and civil buildings. There are many types of fans , which can be divided into centrifugal fans, vane fans , axial fans and Roots blowers. Due to the type and type of fan, the noise and spectral characteristics are different . From the mechanism and characteristics of fan noise, it is mainly composed of four parts: aerodynamic noise of air inlet and exhaust port; electromagnetic noise of motor; solid sound of fan vibration through basic radiation; casing, pipeline, motor Mechanical noise such as bearings. In these four parts, the aerodynamic noise of the inlet and exhaust ports is generally the strongest. According to the actual measurement analysis of the fan, the aerodynamic noise of the fan is about 1 2 ~ 2 5 dB(A) higher than that of other parts . Therefore, the aerodynamic noise should be considered first for noise control of the fan .

Classification of fan noise spectrum characteristics

A large number of on-site measurements and mechanism analysis of noise generated by the fan show that the fan noise spectrum can be properly classified. For example, in a common centrifugal fan, the number of blades is 10~12, and when the number of revolutions is 250~1450r/min, the fundamental frequency falls within the range of 63~125Hz of the octave center frequency, and the main frequency range is 125~2000Hz. When the number of revolutions is 1450~2900r/min, the fundamental frequency falls within the range of 250~500Hz of the octave center frequency, and the important frequency range is 250~4000Hz. The peak value of the centrifugal fan is generally above 500 Hz, and the important frequency band ranges from 125 to 4000 Hz or 250 to 8000 Hz, which is broadband noise. In this way, according to the distribution characteristics of the octave maximum sound pressure level, the fan noise can be divided into five categories: special low frequency, low frequency, intermediate frequency, high frequency, and wide frequency.

Before noise management of the fan, it is necessary to know in detail the noise status of the fan and the unit. This includes checking data or actual measurements and analyzing the noise spectrum.

The noise of the fan is related to the structure, model, air volume and wind pressure of the fan. Different noise control schemes and measures can be selected according to the noise noise, field conditions and noise control requirements. Generally, it can be divided into the installation of sound insulation cover, installation of muffler, vibration reduction and vibration isolation measures .

Installation of sound insulation cover

The fan noise not only propagates along the airflow of the pipeline, but also radiates noise through the ducts of the casing. At the same time, the mechanical noise and electromagnetic noise of the fan unit also propagate outward, polluting the surrounding environment. When the environmental noise standard is high, the noise can not be effectively controlled by only the muffler. The noise control scheme must be considered comprehensively. The most effective measure is to design and install the sound insulation cover of the fan unit.

The sound insulation cover of the unit is mostly closed, and the sound insulation effect of the sound insulation cover is good. However, the use of a closed acoustic enclosure brings the heat dissipation problem of the unit. The temperature rise of the unit, the heat dissipation problem becomes the key to the sound enclosure design. At present, the method of ventilation and cooling in the sound enclosure is generally adopted, and the cooling methods include natural ventilation cooling method and forced ventilation cooling method. It is necessary to strictly calculate the ventilation volume of the sound enclosure by the air volume of the fan and the heat generated by the unit.

Inlet, outlet port muffler installed

The most effective measure for aerodynamic noise control of wind turbines is to install muffler at the inlet and outlet of the fan. The fan-mounted muffler can be installed with a muffler at the air inlet according to the noise control area and the noise reduction target; a muffler is installed at the air outlet; and a muffler is installed on the inlet and outlet pipes. When the noise reduction requirement is high, multiple mufflers need to be installed, and the muffler should be installed in sections.

When designing or selecting a muffler, the muffler frequency characteristics and resistance loss of the muffler must be considered. While the muffler satisfies the muffling amount, the resistance loss should also be controlled within the allowable range. In addition, it is also necessary to consider the use environment of the muffler, such as waterproof, dustproof, fireproof, etc., otherwise it will affect the muffler performance of the muffler.

To formulate a comprehensive control plan for wind turbine noise, it is necessary to combine the actual situation on the site. It is best to consider the noise control problem before selecting the fan and installing the fan. This can reduce the economic cost of the fan noise, easy construction, and more conducive to achieve good noise control.

Shenzhen Quilter noise reduction Engineering Co., Ltd. is specialized in the fan and fan noise noise noise control, product development, design, construction acoustics solutions and is committed to the comprehensive management of fan noise and vibration as one of the engineering and technology companies, professional and study and solve the fan noise, for different types of fans and fan room noise control equipment, to provide users with on-site noise surveys, analysis, system fan noise to provide solutions and construction services.

Main business:

Civil use: Noise reduction in residential quarters and residential houses , noise control in pump house, noise control in air conditioning systems, noise control in generator rooms, noise control in power distribution rooms, noise control in transformer rooms, noise control between machinery and equipment , hotel, office and office space Acoustic noise reduction , acoustic design and construction of functional buildings such as conference centers, concert halls, stadiums, and theaters.

Industry: noise control of mechanical equipment, noise reduction, noise reduction , noise reduction of medical equipment, noise reduction, noise reduction of workshops, sound insulation and noise reduction, noise reduction of fan room, noise reduction of air compressor room , equipment production line noise reduction and other production equipment noise and environmental noise control in the plant area, sound insulation, shock absorption, noise reduction and other comprehensive noise control projects. All kinds of sound insulation doors, sound insulation windows, sound insulation rooms, sound insulation covers, sound insulation screens and other sound insulation projects.