MCD0300128001 模块用于控制传输速度 Kollmorgen
规范和规范内的设计。有关本主题的进一步讨论，请参阅参考文献2。
1.5流体力学*
流体力学是物理学的一个基本领域
流体在静止和运动时的行为。它涉及财产
指流体，如密度和粘度，并涉及
物理，如热力学和传热，增加了
基本流体流功能的能量问题。就这一点而言
在提醒段落中，请记住：
流体系统中某点的静压与流体密度和流体柱高度成正比。静态压力在所有方向上施加相等。
流动流体的速度压力与平方成正比
流体速度；i、 即速度倍增，速度压力倍增。
管道中流动的流体的摩擦损失与
速度的平方。
移动流体所需的泵送功率与
流体密度和粘度，以及处理的流体体积
以及流体被泵送的压力。
由于摩擦损失与流量的平方成正比
定义系统中的泵送功率与
流量的立方。
出于暖通空调目的，空气被视为不可压缩流体。
对于不可压缩流体，封闭系统中的流体量为
常数任何流出都必须被等价的流入抵消，或者
系统中保持的流体量必须发生变化。这是
质量守恒定律允许我们考虑流体在
就像我们在银行里数钱一样。详见参考文献3
讨论这个主题。
*另见16章。
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7
1.6热力学*
热力学与物质的热特性有关
与宇宙的自然亲和力，从更高到更高
低能量状态。热力学研究物质的能力
接受能量水平的变化（将比热作为一种特性）
并将焓作为能量水平的测量尺度）。为此
在提醒段落中，请记住：
物质的能量接受能力称为比热
英制单位为Btu每磅每华氏度。水
比热为
MCD0300128001 模块用于控制传输速度 Kollmorgen
MCD0300128001 模块用于控制传输速度 Kollmorgen
w the codes and to design within them. See Ref. 2 for further discussion of this topic.
1.5 Fluid Mechanics*
Fluid mechanics, a fundamental area of physics, has to do with the
behavior of fluids, both at rest and in motion. It deals with properties
of fluids, such as density and viscosity, and relates to other aspects of
physics, such as thermodynamics and heat transfer, which add the
issues of energy to the functions of the basic fluid flow. For this brief
reminder paragraph, remember:
The static pressure at a point in a fluid system is directly proportional to the density of the fluid and to the height of the fluid column. Static pressure is exerted equally in all directions.
The velocity pressure of a flowing fluid is proportional to the square
of the fluid velocity; i.e., doubling the velocity quadruples the velocity pressure.
The friction loss of a fluid flowing in a conduit is proportional to the
square of the velocity.
The pumping power required to move a fluid is proportional to the
fluid density and viscosity, as well as the volume of fluid handled
and the pressure against which the fluid is pumped.
Since the friction loss is proportional to the square of the flow, the
pumping power in a defined system is proportional overall to the
cube of the flow rate.
For HVAC purposes, air is considered to be an incompressible fluid.
For incompressible fluids, the amount of fluid in a closed system is
constant. Any outflows must be offset by equivalent inflows, or there
must be a change in the amount of fluid held in the system. This is
the Law of Conservation of Mass and allows us to account for fluid in
a process just as we count money in the bank. See Ref. 3 for further
discussion of this topic.
*See also Chap. 16.
HVAC Engineering Fundamentals: Part 1
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HVAC Engineering Fundamentals: Part 1 7
1.6 Thermodynamics*
Thermodynamics has to do with the thermal characteristics of matter
and with the natural affinity of the universe to go from a higher to a
lower energy state. Thermodynamics deals with the ability of matter
to accept changes in energy level (relates to specific heat as a property
and to enthalpy as a scale of measurement of energy level). For this
reminder paragraph, remember:
The energy acceptance capacity of a substance is called specific heat
with English units of Btu per pound per degree Fahrenheit. Water
with a specific heat o
MCD0300128001 模块用于控制传输速度 Kollmorgen
