Method for Solving Noise of ventilation fan

2019-02-16 14:16:40 金晓

With the significant improvement of people's health awareness and the continuous improvement of their quality of life, ventilation fan has become an indispensable part of home decoration.  With the popularization of ventilation fan, people pay more and more attention to it.  A few days ago, someone asked, will the ventilation fan produce noise when it is running?  Xiao Bian solemnly told everyone that the ventilation fan is a mute system.  First of all, we need to know that any machine will produce noise when running.  The only difference is the difference in size.  When we use fresh air, we also produce certain noise, which will not affect people's life under normal circumstances.

There are two main noise sources in the ventilation fan, one is the noise of the fresh air main engine itself, and the other is the noise after installing the main engine and pipes.  As for the noise of the main engine itself, the common fans in China are silent fans with sound-absorbing materials installed, which greatly reduce the noise.  Many companies use silent fresh air main engines.  Under certain special circumstances, mute equipment should be installed after installing the host to ensure very low final noise.  The main engine installed with fresh air has two main noise sources: A, the noise generated by the operation of the fan of the main engine and the vibration of the main engine.  B, the impact of reflux air flow and noise generated by friction pipes and tuyeres.

silent duct fan

How to mute the ventilation fan?

Apart from the mute design of the main unit itself, the mute of the ventilation fan mainly depends on its installation mode.  If the installation is reasonable, there is basically no noise.  Regarding how to reduce system noise during installation, we will take the ducted fan as an example to introduce in detail:

The power source used for replacing indoor and outdoor air and sucking outdoor air is a fresh air main engine, and a fan motor is arranged inside the fresh air main engine to drive air through the rotation of the fan and then form airflow.  The main engine of fresh air is the main noise source of ventilation fan.  When the rotating sound of the fan motor and the airflow sound are superimposed together, a certain noise will be generated.  In order not to affect the normal work and rest activities of indoor personnel, the fresh air main engine should be installed far away from the work and rest areas, such as the ceiling of storage room and toilet, which can effectively reduce the influence of noise.

ventilation fan

The equipment uses shock absorbers and sound insulation cotton.

As the equipment may vibrate, the boom of the main engine is actually very delicate.  In theory, it is best to use shock-absorbing slings, and then place glass sound insulation cotton under the main engine to isolate it.  If the ceiling is not effective enough, sound absorbing materials can be pasted under indoor conditions.  Reduce the noise caused by resonance or motor operation during equipment operation and provide a quiet and comfortable ventilation fan.

greenhouse fan

The ventilation fan reasonably selects the air distribution plenum, and the advantages of installing special air distribution plenum fresh air are as follows:

 1. Reduce dynamic pressure, increase static pressure, stabilize airflow and reduce airflow vibration.  Air volume is evenly distributed.

 2. The air distribution plenum adopts a special air duct design, which can balance the air output from the air outlet and reduce the noise from the air outlet.

 3. According to different areas, adjust the air volume through the air volume control valve of the air distribution box to ensure that the air velocity at the air outlet will not be too large.

Reasonable Use of Mufflers

For selecting large equipment and equipment with high static pressure, special silencers can be considered for fresh air during installation.  The silencing pipe is made of metal, PVC and other materials, and mainly consists of a multi-layer structure.  Sound absorbing material is arranged in the sound absorbing pipe, which can reduce the noise of the equipment main pipe, and the noise will not be transmitted to the end tuyere along with the pipe.

The pipeline is connected with the fresh air main engine.

When the ventilation fan works, it will produce certain vibration and vibration, as well as certain noise.  If the vibration of the fresh air main engine is transmitted to the pipeline, causing the pipeline to vibrate, noise will easily be generated.  In order to prevent the pipeline from being affected by vibration, it is impossible to directly connect the hard pipe to the fresh air main unit.  The connection between fresh air main engine and pipeline shall be hose connection, which can buffer I!

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