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　　1.合理選擇通風機的機型。在噪聲控制要求高的場合，應選用低噪聲通風機。不同型號的通風機，在同樣的風量、風壓下，機翼型葉片的離心通風機噪聲小，前向板型葉片的離心通風機噪聲大。

1. Reasonably choose the model of ventilation fan. In situations with high noise control requirements, low noise ventilation fans should be selected. Different models of ventilators, under the same air volume and pressure, have lower noise levels for centrifugal ventilators with wing shaped blades and higher noise levels for centrifugal ventilators with forward facing plate shaped blades.

　　2.通風機的工作點應接近最高效率點。同一型號的通風機效北越高，噪聲越小。為使通風機的運行工況點保持在通風機的高效率區，應盡量避免用閥門進行工況調節。如必須在通風機壓出端設閥門時，其設置的最佳位置是距通風機出口1m處。它能使2000Hz以下的噪聲降低。在通風機入口處氣流應保持均勻。

The working point of the ventilation fan should be close to the highest efficiency point. The higher the efficiency of the same model of ventilation fan, the lower the noise. To maintain the operating point of the ventilation fan in the high-efficiency zone, it is advisable to avoid using valves for condition adjustment as much as possible. If it is necessary to install a valve at the outlet of the ventilation fan, the optimal position for setting it is 1 meter away from the outlet of the ventilation fan. It can reduce noise below 2000Hz. The airflow at the entrance of the ventilation fan should be kept uniform.

　　3.在可能條件下適當降低通風機的轉速。通風機的旋轉噪聲與葉輪圓周速度10次方成比例，渦流噪聲與葉輪圓周速度6次方(或5次方)成比例。故降低轉速可降低噪聲。

3. Reduce the speed of the ventilation fan appropriately under possible conditions. The rotational noise of the ventilation fan is proportional to the 10th power of the impeller circumferential speed, and the eddy current noise is proportional to the 6th power (or 5th power) of the impeller circumferential speed. Therefore, reducing the speed can reduce noise.

　　4.通風機進、出口的噪聲級是通風理、風壓增加而增大的。因此，設計通風系統時，應盡量減少系統的壓力損失。當通風系統的總風量和壓力損失較大時，可將其分為小系統。

The noise level at the inlet and outlet of the ventilation fan increases with the increase of ventilation efficiency and wind pressure. Therefore, when designing a ventilation system, efforts should be made to minimize the pressure loss of the system. When the total air volume and pressure loss of the ventilation system is large, it can be divided into small systems.

　　5.氣流在管道內的流速不宜過高，以免引起再生噪聲。確定管道內氣流流速應根據不同要求按有關規定選取。

5. The flow velocity of the airflow in the pipeline should not be too high to avoid causing regeneration noise. The determination of the airflow velocity inside the pipeline should be selected according to different requirements and relevant regulations.

　　6.注意通風機與電動機的傳動方式。采用直聯傳動的通風機噪聲最小，用聯軸器的次之，用沒有接縫的三角皮帶傳動的稍差。通風機應配用低噪聲的電動機。

6. Pay attention to the transmission mode between the ventilation fan and the electric motor. The ventilation fan using direct transmission has the lowest noise, followed by the one using couplings, and slightly worse when driven by a V-belt without joints. Ventilation fans should be equipped with low-noise electric motors.

以上是關于 濟南通風管道 的介紹，若想了解相關知識可請點擊：http://m.xmxdgg.com 我們將會全心全意為您提供滿分服務，歡迎您的來電！

The above is an introduction to Jinan ventilation ducts. If you want to learn more about related knowledge, please click: http://m.xmxdgg.com We will wholeheartedly provide you with full score service. Welcome to call us!