MSK12-10-000-QA MSK1210000QA 模拟量控制驱动器 BAUTZ

MSK12-10-000-QA MSK1210000QA 模拟量控制驱动器 BAUTZ
每个连续倍频程的频率是
前一个。31.5赫兹或每秒周期的振动频率
（Hz）定义一倍频程带的中点。中间C在
五倍频程的中间，频率为504Hz。
声音或噪音是由运动中的物体产生的
空气振动。声音从原点“辐射”到
检测点。露天环境中的声功率级随着
距离的平方，但在较小的受限空间中，具有
声功率级可以在距离上相对恒定。声音可以通过吸收或限制来控制。稠密的
纤维垫和声学管道衬里是吸收材料的例子。砖石或混凝土结构，以及噪音周围的铅织物
发电机是限制（安全壳）的例子。组合
暖通空调工程基础：1部分
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暖通空调工程基础：1部分11
限制和吸收通常用于控制或消除
系统产生声音。
当周期运动的影响
一件设备的一部分被带入并穿过结构
根据定义，感觉到刺激或冒犯的点。
任何稍微失去平衡的旋转设备都可以设置
增加振动。振动通常在结构中传递到远处
要点。坐在书桌旁的人可以感觉到地板或书桌
振动。实验室工作台上的一盘液体可能会呈现波形
表面上的结构振动。即使暴风雨也能
导致建筑物震动，空气在管道中流动或
管道中流动的流体会引起振动和噪音。
好通过平衡和隔离来控制振动。平衡
移动部件消除了其原点的振动。对于大型元件，如风扇、压缩机和发动机，采用弹簧隔离
或弹性垫是常见的做法。较低频率的振动需要更多的初始弹簧偏转才能有效。必须消除振动元件与其环境的任何硬物理连接。因此，所有管道和导管或管道连接必须灵活
有联系的。这也有助于确保设备：
不承受连接管道的重量。
关于这一问题的进一步讨论，见20章和参考文献7。
1.10节能
定期的国际活动提醒我们能源在
发达国家的经济福祉。共同的能力
工业国家的人民比国王过着更富裕的生活
而过去的女王与能源仆人直接相关。
交通、通信、农业、住房、制造业、，
卫生保健服务等都由
可用的能源供应，包括燃料和电力。
同时，可用能源也存在明显的限制
来源。尽管有了新的发现，但煤炭、石油、天然气和其他化石或有机燃料的总量仍可以估算，今年的数据低于
后一个。发展的潜力有限
可再生能源，全部来自太阳，如木材、风能、水力发电等。就规模而言，核能（当时的聚变概念）是一已知的能带来希望的能源
能够使三世界工业化并维持一个不断增长的世界
人口超过几个世纪而不是几十年。然而，核武器的使用
权力深陷政治流沙
MSK12-10-000-QA MSK1210000QA 模拟量控制驱动器 BAUTZ

MSK12-10-000-QA MSK1210000QA 模拟量控制驱动器 BAUTZ
The frequency of each successive octave is
previous. Vibration frequency of 31.5 Hz or cycles per second
(Hz) defines the midpoint of the first octave band. Middle C in
In the middle of the fifth octave, the frequency is 504hz.
Sound or noise is produced by moving objects
Air vibration. Sound "radiates" from the origin to
Detection point. The sound power level in the open air environment changes with
The square of the distance, but in a small confined space, with
The sound power level may be relatively constant over distance. Sound can be controlled by absorption or restriction. Dense
Fiber mats and acoustic duct liners are examples of absorbent materials. Brick or concrete structures and lead fabrics around noise
The generator is an example of restriction (containment). combination
Fundamentals of HVAC engineering: Part 1
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Fundamentals of HVAC engineering: Part 1 11
Limitation and absorption are usually used for control or elimination
The system generates sound.
When the influence of periodic motion
A part of a piece of equipment is brought into and passed through the structure
By definition, the point at which irritation or offence is felt.
Any rotating equipment slightly out of balance can be set
Increase vibration. Vibration is usually transmitted to a distance in the structure
main points. The person sitting at the desk can feel the floor or desk
Vibration. A tray of liquid on the laboratory bench may exhibit waveforms
Structural vibration on the surface. Even a storm can
Cause building vibration, air flow in the pipeline or
The fluid flowing in the pipeline will cause vibration and noise.
Vibration is preferably controlled by balancing and isolation. balance
The moving part eliminates the vibration of its origin. For large components, such as fans, compressors and engines, spring isolation is used
Or an elastic pad is a common practice. Lower frequency vibrations require more initial spring deflection to be effective. Any hard physical connection of the vibration element to its environment must be eliminated. Therefore, all pipes and conduits or pipe connections must be flexible
It's related. This also helps to ensure that the equipment:
It does not bear the weight of the connecting pipe.
For further discussion on this issue, see Chapter 20 and reference 7.
1.10 energy saving
Regular international activities remind us that energy is
The economic well-being of developed countries. Common ability
The people of industrial countries lead a richer life than the king
In the past, the queen was directly related to the energy servant.
Transportation, communication, agriculture, housing, manufacturing,
Health care services are provided by
Available energy supply, including fuel and electricity.
At the same time, there are obvious restrictions on available energy
Source. Despite the new discoveries, the total amount of coal, oil, natural gas and other fossil or organic fuels can still be estimated. This year's data is lower than
the last one. Limited development potential
All renewable energy comes from the sun, such as wood, wind energy and hydropower. In terms of scale, nuclear energy (the concept of fusion at that time) was the only known energy source that could bring hope
It can industrialize the third world and maintain a growing world
The population exceeds centuries rather than decades. However, the use of nuclear weapons
Power is trapped in the quicksand of politics
MSK12-10-000-QA MSK1210000QA 模拟量控制驱动器 BAUTZ