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在工程項目實踐活動中通常出現那樣一種狀況，通風系統出入口風速十分高，乃至做到20~30m/s之上，這時噪聲挺大必須減噪解決。
In the practical activities of engineering projects, there is usually such a situation that the wind speed at the inlet and outlet of the ventilation system is very high, even above 20 ~ 30 m / s. at this time, the noise is very large and must be solved by reducing the noise.
通風系統出入口噪聲這時關鍵由下列二種噪聲源組成：
The noise at the entrance and exit of ventilation system is mainly composed of the following two noise sources:
1、通風降溫設備的機械設備噪聲
1. Mechanical equipment noise of ventilation and cooling equipment
2、髙速的氣流噪聲。
2. High speed airflow noise.
這時若要合理的降低噪聲，除開要考慮到機器設備噪聲以外，另外要考慮到自然通風鍍鋅鋼板通風管道套什么清單:風速的降低。
At this time, in order to reduce the noise reasonably, in addition to considering the noise of machinery and equipment, we should also consider the list of natural ventilation galvanized steel ventilation pipe: the reduction of wind speed.
另外風速的高矮也決策了消聲器的合理長短。
In addition, the height of wind speed also determines the reasonable length of muffler.
一般狀況下，大家會選用自然通風變徑的方法來降低氣流的風速，例如將30m/s的風速降低到十米/s下列的風速。這時消聲器以便更為性價比高，一般選用減速之后的氣流速率設計制作消聲器的長短。
In general, natural ventilation is used to reduce the wind speed of airflow, such as reducing the wind speed from 30 m / s to less than 10 m / s. At this time, the muffler is more cost-effective, and the length of the muffler is generally designed and manufactured according to the airflow rate after deceleration.
這時消聲器的安裝哪個部位較為適合呢？不可以直徑安裝在變徑以后，立即安裝在變徑以后會造成 下列狀況：
Which part of muffler is more suitable for installation? It is not allowed to install the diameter after the diameter change first, but the installation immediately after the diameter change will cause the following conditions:
1、變徑后立即安裝消聲器，則該點氣流渦旋擴大，排風系統摩擦阻力擴大
1. If the muffler is installed immediately after the diameter change, the air flow vortex will expand and the friction resistance of the exhaust system will increase
2、消聲器進口處管理地區氣流趕不及充足衰減系數，立即沖進消聲器，則這時消聲器內具體的氣流速率遠高于消聲通風管道系列器的設計方案氣流速率。則消鍍鋅鋼板通風管道套什么清單:聲器的具體合理長短降低，消聲器預期效果遠不可以做到設計方案規定。
2. If the air flow in the management center area at the inlet of the muffler can't catch up with the sufficient attenuation coefficient, it will rush into the muffler immediately, then the specific air flow rate in the muffler will be much higher than that in the design scheme of the muffler series. Then what list should be set for the ventilation pipe of galvanized steel sheet: the specific and reasonable length of the sounder is reduced, and the expected effect of the muffler is far from meeting the requirements of the design scheme.
恰當的作法是將變徑后的通風風管增加直徑的5~8倍后，氣流做到恒定時情況再安裝消聲器，這時消聲器才可以做到設計效果。
The proper way is to increase the diameter of the reduced ventilation duct by 5 ~ 8 times, and install the muffler when the air flow is constant, then the muffler can achieve the design effect. 上一篇：山東通風管道制作安裝|風管的三種類型
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