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　　1.合理選擇通風(fēng)機(jī)的機(jī)型。在噪聲控制要求高的場合，應(yīng)選用低噪聲通風(fēng)機(jī)。不同型號(hào)的通風(fēng)機(jī)，在同樣的風(fēng)量、風(fēng)壓下，機(jī)翼型葉片的離心通風(fēng)機(jī)噪聲小，前向板型葉片的離心通風(fēng)機(jī)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(fēng)機(jī)的工作點(diǎn)應(yīng)接近最高效率點(diǎn)。同一型號(hào)的通風(fēng)機(jī)效北越高，噪聲越小。為使通風(fēng)機(jī)的運(yùn)行工況點(diǎn)保持在通風(fēng)機(jī)的高效率區(qū)，應(yīng)盡量避免用閥門進(jìn)行工況調(diào)節(jié)。如必須在通風(fēng)機(jī)壓出端設(shè)閥門時(shí)，其設(shè)置的最佳位置是距通風(fēng)機(jī)出口1m處。它能使2000Hz以下的噪聲降低。在通風(fēng)機(jī)入口處氣流應(yīng)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(dāng)降低通風(fēng)機(jī)的轉(zhuǎn)速。通風(fēng)機(jī)的旋轉(zhuǎn)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(zhuǎn)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(fēng)機(jī)進(jìn)、出口的噪聲級(jí)是通風(fēng)理、風(fēng)壓增加而增大的。因此，設(shè)計(jì)通風(fēng)系統(tǒng)時(shí)，應(yīng)盡量減少系統(tǒng)的壓力損失。當(dāng)通風(fēng)系統(tǒng)的總風(fēng)量和壓力損失較大時(shí)，可將其分為小系統(tǒng)。

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(nèi)的流速不宜過高，以免引起再生噪聲。確定管道內(nèi)氣流流速應(yīng)根據(jù)不同要求按有關(guān)規(guī)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(fēng)機(jī)與電動(dòng)機(jī)的傳動(dòng)方式。采用直聯(lián)傳動(dòng)的通風(fēng)機(jī)噪聲最小，用聯(lián)軸器的次之，用沒有接縫的三角皮帶傳動(dòng)的稍差。通風(fēng)機(jī)應(yīng)配用低噪聲的電動(dòng)機(jī)。

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(guān)于 濟(jì)南通風(fēng)管道 的介紹，若想了解相關(guān)知識(shí)可請點(diǎn)擊：http://www.a2862.cn 我們將會(huì)全心全意為您提供滿分服務(wù)，歡迎您的來電！

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