6SM107K-3000 6SM107K-3000-SI 伺服电动机 Kollmorgen
o在不进行必要的建筑和结构修改的情况下，试图按照洁净室规范对其进行空调将是徒劳的。虽然大多数示例比这更微妙，但许多HVAC
系统不能令人满意地运行，因为基本建筑物：
不适当的设计师必须能够认识到这一点。
还需要了解建筑物的使用和
大多数建筑物使用每个部分。这种使用如何影响占用率、活动水平、湿度、温度和通风要求？在设计合适的HVAC系统之前，设计师必须对这些问题和许多其他问题有答案。
2.2舒适性
“舒适”是一个高度主观的词，反映了不同的感觉
从一个人到另一个人的差异很大。舒适度只能定义为：
来源：暖通空调系统设计手册
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16二章
一般或统计术语。ASHRAE多年来的研究
确定了影响舒适度的主要因素：温度，
相对湿度、空气运动和辐射效应。试图
已将这些因素组合起来以获得单个数字索引
称为有效温度1或舒适指数。服装的类型和数量以及活动水平也会影响舒适度，但是
因素变化很大，无法量化。
通常，空气系统设计用于始终控制温度
有时还有湿度。良好的空气流动控制（来自供应
格栅和扩散器）以提高舒适性指数。
人们不喜欢通风（局部空气速度超过约100英尺/分钟），
但是在一些炎热的工业环境中
可能需要工作站。辐射效应通常超出
暖通空调设计师的控制，但应在
暖通空调设计。典型的辐射效应是由窗户引起的（冷
冬季，暴露在阳光下时很热），通过照明设备（尤其是
白炽）和在大群体中的人之间的交叉辐射。
辐射效果有时可以通过提供辐射面板来抵消
其根据需要被冷却或加热。有一个有趣的图表
在ASHRAE手册中，该手册绘制了
在任何给定温度下都不满意。它可以解释为：
70至75华氏度之间的一般舒适度范围，但也表明
没有任何温度能让每个人都满意
2.3湿度测量的使用
湿度测量学是研究空气-水蒸气混合物的物理性质，通常称为湿空气。由于空气是大多数空调过程中的终能量传输介质，因此它是
暖通空调设计中的基本工具。19章讨论了湿度
原则和更详细的讨论可在ASHRAE手册基本原理中找到。3.许多不同的湿度图
可从各种来源获得。本书使用了ASHRAE图表
和桌子。
作者（海恩斯）绘制了高空湿度图
在20世纪50年代，用于他的设计工作
随时可用。图表的格式与
该时期的ASHRAE海平面图。几个的表格值
高度是手工计算的，手工绘图技术是：
习惯于
ASHRAE现在有一张海拔5000英尺的海图。
2.4暖通空调循环
图2.1是基本机械系统的示意图
冷却循环。而除湿为n
6SM107K-3000 6SM107K-3000-SI 伺服电动机 Kollmorgen
6SM107K-3000 6SM107K-3000-SI 伺服电动机 Kollmorgen
o attempt to air-condition it to clean-room specifications without making the necessary architectural and structural revisions would be futile. While most examples are more subtle than this, many HVAC
systems do not perform satisfactorily because the basic building is
unsuitable. Designers must be able to recognize this.
It is also necessary to understand the use of the building and in
most buildings the use of each part. How does this use affect occupancy, activity level, humidity, temperature, and ventilation requirements? Designers must have answers to these and many other questions before they can design a suitable HVAC system.
2.2 Comfort
Comfort is a highly subjective word, reflecting sensations which vary
greatly from one individual to another. Comfort can be defined only in
Source: HVAC Systems Design Handbook
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16 Chapter Two
general or statistical terms. Research by ASHRAE over many years
has identified the major factors contributing to comfort: temperature,
relative humidity, air movement, and radiant effects. Attempts have
been made to combine these factors to obtain a single-number index
called the effective temperature1 or comfort index. The type and quantity of clothing and the level of activity also affect comfort, but these
factors vary so greatly that they cannot be quantified.
Typically, the air system is designed to control temperature always
and humidity sometimes. Good control of air movement (from supply
grilles and diffusers) is also needed to improve the comfort index. Most
people do not like a draft (local air velocity over about 100 ft/min),
but in some hot industrial environments, a high rate of airflow at the
workstation may be necessary. Radiant effects are often beyond the
control of the HVAC designer but should be taken into account in the
HVAC design. Typical radiant effects are caused by windows (cold in
winter, hot when exposed to the sun), by lighting fixtures (especially
incandescent), and by cross-radiation among people in large groups.
Radiant effects can sometimes be offset by providing radiant panels
which are cooled or heated as needed.1 There is an interesting graph
in the ASHRAE Handbook which plots the percentage of people who
are dissatisfied at any given temperature. It can be interpreted to read
a range of general comfort between 70 and 75F, but it also shows that
there is no temperature at which everybody will be satisfied.2
2.3 Use of Psychrometrics
Psychrometrics is the study of the physical properties of air-water vapor mixtures, commonly called moist air. Because air is the final energy transport medium in most air conditioning processes, it is an
essential tool in HVAC design. Chapter 19 discusses psychrometric
principles, and a more detailed discussion can be found in the ASHRAE Handbook Fundamentals.3 Many different psychrometric charts
are available from various sources. This book uses the ASHRAE charts
and tables.
The author (Haines) constructed high altitude psychrometric charts
in the 1950s, for use in his design work when such charts were not
readily available. The charts were made to the same format as the
ASHRAE sea-level chart of that period. Tabular values for several
altitudes were hand calculated and hand-drafting techniques were
used.
ASHRAE now has a chart for 5000-ft elevation above sea level.
2.4 HVAC Cycles
Figure 2.1 is a schematic representation of an elementary mechanical
cooling cycle. While dehumidification is n
6SM107K-3000 6SM107K-3000-SI 伺服电动机 Kollmorgen
