建筑环境与设备工程专业英语

Heat Transfer

1 Conduction Words and Expressions

1.Heat transfer 传热学

heat transfer 传热，热传递

coefficient of heat transfer 传热系数

steady-state heat transfer 稳定传热

unsteady-state heat transfer 非稳态传热

2.discipline n. ①纪律 ②训练③学科

[ disiplin]

①formation discipline 队列纪律

②programming discipline 程序设计训练

③engineering discipline 工程学科

3.flow v. 流动 n. 流量

① flow to 从…….流……

flow field 流场

②flow of stream 蒸汽流量

flowmeter 流量计

4.conduction n. （热、电等的）传导

[k n d k n]

thermal conduction 热传导

[词性变化]

conductor 导体

non-conductor 非导体

conductivity n. 传导性,传导率

thermal conductivity 导热系数，导热率

5.displacement n. ①置换，取代②排水量

[dis pleism nt] ③位移

① displacement ventilation 置换通风

② displacement ton 排水量吨

a ship with a displacement of 1000 tons

排水量为1000吨的船

③ absolute displacement

绝对位移

6.gradient n. 坡度，梯度

[ greidi nt]

temperature gradient

grade 等级

grade of concentration 浓缩度

centigrade 摄氏度

7. ①profile 剖面图，断面图

profile in elevation 立面图

②figure只有“图”的含义，与图的内容，作用无关

figure 1 图1

③chart 侧重指计算图，可以用该图进行计算

temperature-entropy chart 温熵图

pressure-volume chart 压容图

④drawing 有“草图”的含义，可以其他词一起表示其他的含义 general drawing 总图 constructional drawing 施工图

8.minus adj. 负的 prep.减去 n.减号；负数；

[ main s]

minus sign 负号

Seven minus four equals three.

反义词：plus

plus sign 正号

Four plus three equals Seven.

9.dimension n. 尺寸，大小，因次

[di men n] general dimension 总尺寸

[词性变化]

dimensional adj.

one-dimensional 一维的

multidimensional 多维的

dimensionless 无因次的

dimensionless parameter 无量纲参数

10. cross sectional area 横截面积

cross adj.交叉的；相反的

cross flow 逆流

cross valve 四通阀门

cross ventilation 穿堂风

section 截面，区域，区段

closed section pipe 封闭的管段

11.boundary n. 边界,分界线

[ baundri] boundary layer 边界层

thermal boundary layer 热边界层

boundary condition 边界条件

bound v. 跳跃，划界限

12.sink ① n.洗涤池，洗涤盆②v. 使沉没

[si k] ③ n.汇，汇点

① sink water trap 存水湾

② sink pump 潜水泵

③ sink flow 汇流

heat sink 热汇

Text

1. In the simplest of terms, the discipline of heat

transfer is concerned with only two things:

temperature, and the flow of heat. Temperature

represents the amount of thermal energy available,

whereas heat flow represents the movement of

thermal energy from place to place. Heat transfer is

energy transferred because of a temperature

difference. Energy moves from a high-temperature

region to a low-temperature region by one or more

three modes: conduction, radiation, and convection.

2. Heat transfer by conduction may be thought of

as the heat transfer through a substance from a

region of high temperature to a region of low

temperature by the progressive exchange of energy

between the molecules of substance.

through a substance from a region of high temperature

to a region of low temperature 介词短语作地点状语

by the progressive exchange of energy

介词短语作方式状语

between the molecules of substance修饰 the

progressive exchange of energy

progressive adj. 渐进的，进步的

[pr ɡresiv]

2. In the process of transferring heat by conduction

, no bodily displacement of the molecules occurs.

In the case of metals, however, electron

movement greatly assists in heat transfer by

conduction.

assist in：在……给予帮助

在导热过程中，没有产生分子的具体的位移。然

而，就金属来说，自由电子的运动大大有助于导

热。

3. When a temperature gradient exists within a

body, heat energy will flow from the region of high

temperature to the region of low temperature. The

phenomenon is known as conduction heat

transfer, and is described by Fourier's Law (named

after the French physicist Joseph Fourier),

译文：当物体内部存在温度梯度时，将有热量从高

温区域传导低温区域，这一现象被称为热传导，由

傅里叶定律描述为

4.

This equation determines the heat flux vector q for

a given temperature profile T and thermal

conductivity k. The minus sign ensures that heat

flows down the temperature gradient.

vector [ vekt ] n. 向量,矢量

Flux：流量

5. For problems where the temperature variation is 1-dimensional, Fourier s Law of heat conduction simplies to the scalar equations,

Where the heat flux q depends on a given

temperature profile T and thermal conductivity k.

The minus sign ensures that heat flows down the

temperature gradient.

scalar [ skeil ] 标量(的)

—— the temperature gradient in the

direction of the heat flow

6. In the above equation on the right, Q represents the heat flow through a defined cross-sectional area A, measured in watts,

7. Heat energy transfers between a solid and a

fluid when there is a temperature difference

between the fluid and the solid. This is known as

"convection heat transfer". Generally, convection

heat transfer can not be ignored when there is a

significant fluid motion around the solid.

convection heat transfer

对流换热

2 Convection

Words and Expressions

1.convection [k n vek n] n. 对流

thermal convection ural热对流

forced convection 强制对流

natural / free convection 自然对流

convective adj. 对流的

convective heat transfer 对流换热

convector n. 对流散热器

2. suction device 吸引装置

suction n. 吸，抽吸

suction velocity at return air inlet

回风口吸风速度

suction pressure 吸气压力

3. plate n. 金属板,板块,盘

plate heat exchanger 板式换热器

plate-fin coil 翅（肋）片盘管

4. buoyancy [ b i nsi] n. 浮力,弹性

buoyancy force 浮力

5. inertia [in : i ] n. 惯性,惰性

inertia force 惯性力

inertial adj. 惯性的

inertial dust separator 惯性除尘器

inert [in :t] adj. 惰性的

inert gas 惰性气体

6. current adj. 现在的，最近的；

n. (气流，水流，电流）流动=flow

current standards 现行标准

electric current 电流

cross current 交叉气流

7. exposed adj. 暴露的

exposed area 外露面积，围护结构面积

exposed pipe 明装管道

expose vt. 暴露，揭露

8. diffusion [di fju: n] n. 扩散

atmospheric diffusion 大气扩散

diffuse vt. 扩散

diffusivity [difju siviti] 扩散率

thermal diffusivity 热扩散率

diffuser 散流器

系数

※thermal conductivity 导热系数

※coefficient of convective heat transfer

对流换热系数

※coefficient of heat transfer 传热系数

※mass-transfer coefficient 传质系数

※thermal diffusivity 热扩散率

※radiation heat transfer coefficient 辐射换热系数

9. concentration 浓度

dust concentration 含尘浓度

concentrate on 专心于

concentrated adj. 集中的

concentrated air conditioning 集中空调

concentrated cooling 集中供冷

concentrated heating 集中供暖

10.formula[ f :mjul ] n. 公式，化学式

molecular formula 公式

form n. 形式 v. 形成,建立

11. stream n. (小河,水流,(人,车,气)流

[stri:m] v. 流动=flow

downstream 顺喷

upstream 逆喷

8. Natural convection occurs when a system

becomes unstable and there begins to mix by the

movement of mass. A common observation of

convection is of thermal convection in a pot of

boiling water, in which the hot and less-dense

water on the bottom layer moves upwards, and the

cool and more dense water near the top of the

pot likewise sinks. The onset of natural convection

is determined by the Rayleigh number(Ra)

pot n. 罐；壶；

[p t] a pot of water 一壶水

10. Forced convection is a type of heat transport in

which fluid motion is generated by an external

source (like a pump, fan, suction device, etc.). Forced convection is often encountered by engineers designing or analyzing heat exchangers,

pipe flow, and flow over a plate at a different

temperature than the stream .

10. However, in any forced convection situation,

some amount of natural convection is always

present whenever there are g-forces present (i.e.,

unless the system is in free fall). When the natural

convection is not negligible, such flows are

typically referred to as mixed convection.

G力（G-Force）原为一航空专有名词，现在广泛做

为高速移动时承受力道的单位。G即为一个地球表面

的重力加速度，在航空中1G定义为航空机在海平面

飞行时的升力和受到地球引力而往下吸引的力量相

平衡时；而当飞行器改变惯性，如加减速或是进行

非直线动作时即会产生正或负的G力。

11. When analyzing potentially mixed convection,

a parameter called the Archimedes number (Ar) parametizes the relative strength of free and forced convection.

potentially [p ten li] ：adv. 潜在地

parameter [p 'ræm t (r)] n.参量；参数

strength n.力气；强度；

翻译：在分析潜在的混合对流现象时，阿基米德数 可用来比较自然对流及强制对流的相对强度。

11.The Archimedes number is the ratio of Grashof number and the square of Reynolds number, which represents the ratio of buoyancy force and inertia force, and which stands in for the

contribution of natural convection. When Ar >> 1, natural convection dominates and when Ar << 1, forced convection dominates.

square n.正方形；平方；dominate：占用主要地位 buoyancy force：浮力

inertia force：惯性力

12.When natural convection isn't a significant factor, mathematical analysis with forced

convection theories typically yields accurate results. The parameter of importance in forced convection is the Peclet number, which is the ratio of advection (movement by currents) and diffusion (movement from high to low concentrations) of heat.

14.The rate of heat transferred to the surrounding fluid is proportional to the object's exposed area A, and the difference between the object temperature Tw and the fluid free-stream temperature T∞.