83SR07A-E GJR2392700R1210 83SR07 控制驱动器 ABB
设计师。因为内部环境通常比
需要外部空气、绝缘和蒸汽屏障，以防止
结构空腔中的冷凝。不遵守这一责任可能导致建筑物的早期损坏。游泳池
加湿建筑物（医院等）尤其脆弱。关于本主题的进一步讨论，见参考文献6和19章。
1.9声音和振动*
声音和振动已成为暖通空调领域的一个热门话题
设计师，不是说它们是主要加热、冷却和
*另见20章。
暖通空调工程基础：1部分
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10.一章
空调功能，但因为它们是次要因素
如果处理不当，可能会破坏其他成功的
暖通空调安装。
所有声音和振动都是动能的形式
暖通空调世界它们通常来源于移动设备，移动
空气、减压设备或其他移动流体。问题
HVAC系统部件产生噪音或振动时发生
在有人居住或过程敏感的空间内或附近。如果产生的声音或振动水平超过当地公差水平
暖通空调系统被视为不合格。
为了使暖通空调系统在声音和振动方面可接受，服务空间内的居住者或过程必须基本上：
不知道或至少不受
暖通空调系统。办公室或剧院中的空气传播声音不得产生
关注自身。当一切静止时，空间必须看起来安静，并且
允许谈话或音乐在没有干扰的情况下继续。同样
对于振动也是如此。暖通空调系统的运行不应经常
在振动的意义上，不得对建筑物使用者明显
地板或书桌，或像灯具一样的可视移动结构部件。认识到，在不太复杂的空间，如商店或设备室，预计会出现一些声音和振动，并且在
更别，因此HVAC设计师必须首先了解起源，
然后是可接受的性能水平，后是机制
控制声音和振动，以达到可接受的服务水平。
“声音”是传输到
耳或等效声传感装置。当声音冒犯时
这叫做“噪音”声功率级以瓦特为单位测量，并且
10 12 W为听力阈值，定义为0分贝
（dB）。声音通常在每个倍频带内测量，
其中，每个连续倍频带的频率是
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
生成器是conf的示例
83SR07A-E GJR2392700R1210 83SR07 控制驱动器 ABB
83SR07A-E GJR2392700R1210 83SR07 控制驱动器 ABB
designers. Since the inside environment usually is moister than the
outside air, insulation and vapor barriers are required to prevent
condensation in the structural cavities. Failure to respect this liability may lead to early deterioration of a building. Swimming pools
and humidified buildings (hospitals, etc.) are particularly vulnerable. See Ref. 6 and Chap. 19 for further discussion of this topic.
1.9 Sound and Vibration*
Sound and vibration have become a topic of interest for the HVAC
designer, not that they are part of the primary heating, cooling, and
*See also Chap. 20.
HVAC Engineering Fundamentals: Part 1
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10 Chapter One
air conditioning functions but because they are secondary factors
which, if not properly handled, can destroy an otherwise successful
HVAC installation.
All sounds and vibrations are forms of kinetic energy, and in the
HVAC world they are usually derived from moving equipment, moving
air, pressure-reducing equipment, or other moving fluid. A problem
arises when an HVAC system component generates noise or vibration
within, or adjacent to, a habited or process-sensitive space. If the generated sound or vibration level exceeds the local tolerance level, the
HVAC system is deemed unacceptable.
For an HVAC system to be acceptable in terms of sound and vibration, an occupant or a process in a served space must be essentially
unaware of, or at least not impaired by, the active functions of the
HVAC system. Airborne sound in an office or theater must not draw
attention to itself. The space must seem quiet when all is still, and
allow conversation or music to go on without intrusion. The same is
true for vibration. Operation of the HVAC system should not, often
must not, be apparent to building occupants in the sense of a vibrating
floor or desk, or visibly moving structural components like a light fixture. Recognize that in less sophisticated spaces like shops or equipment rooms, some sound and vibration is expected and tolerated at
higher levels, so the HVAC designer must understand first the origins,
then the level of acceptable performance, and finally the mechanisms
of control of sound and vibration to achieve an acceptable level of service.
‘‘Sound’’ is a generic term for airborne vibrations transmitted to the
ear or equivalent acoustic sensing device. When sound offends, it is
called ‘‘noise.’’ Sound power levels are measured in watts, and with
1012 W being a threshold of hearing, this is defined as being 0 decibels
(dB). Sound is usually measured within and for each octave band,
where the frequency of each successive octave band is twice that of
the previous. A vibration frequency of 31.5 hertz or cycles per second
(Hz) defines the midpoint of the first octave band. Middle C is in the
middle of the fifth octave band at 504 Hz.
Sound or noise is generated by something in motion which sets up
airborne vibration. The sound ‘‘radiates’’ from the point of origin to
the point of detection. Sound power levels in open air diminish with
the square of the distance, but in a smaller confined space, with high
reflectance, the sound power level may be relatively constant over distance. Sound may be controlled by absorption or confinement. Dense
fibrous mats and accoustical duct liner are examples of absorptive materials. Masonry or concrete structure, and lead fabrics around a noise
generator are examples of conf
83SR07A-E GJR2392700R1210 83SR07 控制驱动器 ABB
