西安建筑科技大学：《工程热力学 Engineering Thermodynamics》课程双语教学资源（PPT课件讲稿）第一章 基本概念 Basic Concepts

0·0000000鲁00000春 0000000000000 第一章基本概念 Chapter 1. Basic Concepts LOGO

LOGO 第一章 基本概念 Chapter 1. Basic Concepts

Contents 1. Thermodynamic system 热力系统 2. Properties of A System 系统的状态参数 3. State and Equilibrium 状态及平衡状态 4. Process and cycles 过程与循环 www.themegallery.com Company Logo

www.themegallery.com Company Logo Contents 1. Thermodynamic System 热力系统 2. Properties of A System 系统的状态参数 3. State and Equilibrium 状态及平衡状态 4. Process and Cycles 过程与循环

8 1.1 Thermodynamic System::::::9:::::::::. 热力系统 1. Systen(热力系统的定义) a quantity of matter or a region in space chosen for study (系统就是指被选做研究对象的物体或空间。) For example: Inlet Boundary System Turbine Output Work I Outlet Surroundings Surroundin 气缸活塞装置 汽轮机 Cylinder-piston equipment Steam turbine www.themegallery.com Company Logo

www.themegallery.com Company Logo §1.1 Thermodynamic System 热力系统 1. System （热力系统的定义 ） A quantity of matter or a region in space chosen for study. （系统就是指被选做研究对象的物体或空间。） For example: 气缸-活塞装置 Cylinder-piston equipment 汽轮机 Steam turbine

00 2. System, Surroundings and boundary 系统、外界和边界 (1) Surroundings(外界) The mass or region outside the system is called surroundings (2) Boundary(边界) The real or imaginary surface that separates the system from its surroundings is called boundary (3) Interactions between system and its surroundings(系统与外界 间的相互作用) There are mass or energy exchange between system and its surroundings. And they must cross the boundaries 系统与外界之间有质量及能量的交换,且都必须穿越边界 www.themegallery.com Company Logo

www.themegallery.com Company Logo (1) Surroundings（外界） The mass or region outside the system is called surroundings. (2) Boundary（边界） The real or imaginary surface that separates the system from its surroundings is called boundary. (3) Interactions between system and its surroundings (系统与外界 间的相互作用） There are mass or energy exchange between system and its surroundings. And they must cross the boundaries. 系统与外界之间有质量及能量的交换，且都必须穿越边界 2. System, Surroundings and boundary 系统、外界和边界

00 (4)Characteristics of boundaries Boundaries are selected subjectively 边界是人为选定的 Boundaries can be fixed or movable 边界可以是固定的,也可以是可移动 Boundaries can be real or imaginary. 边界可以是真实的,也可以是假想的 www.themegallery.com Company Logo

www.themegallery.com Company Logo (4) Characteristics of boundaries ▪ Boundaries are selected subjectively 边界是人为选定的. ◼ Boundaries can be fixed or movable. 边界可以是固定的，也可以是可移动 ◼ Boundaries can be real or imaginary. 边界可以是真实的，也可以是假想的

Mass entering or leaving the system System Mass exchange Surroundings Energy exchange Energy entering or leaving the system Energy can cross the boundary, in the form of heat and wor www.themegallery.com Company Logo

www.themegallery.com Company Logo System Surroundings Mass exchange Energy exchange Mass entering or leaving the system Energy entering or leaving the system Energy can cross the boundary, in the form of heat and work

热力系统选取的人为性: 过热器 Only work exchange (reheater) 汽轮机 turbine) 锅 炉 boiler 发电机 generator Work and heat exchange 凝汽得 (condenser 给水泵(pump) Only heat exchange www.themegallery.com Company Logo

www.themegallery.com Company Logo 热力系统选取的人为性： 锅 炉 boiler 汽轮机(turbine) 发电机(generator) 给水泵(pump) 凝汽器 (condenser) 过热器 (reheater) Only work exchange Only heat exchange Work and heat exchange

00 fixed、 movable real、 Imaginar 固定、活动 真实、虚构 www.themegallery.com Company Logo

www.themegallery.com Company Logo 固定、活动 真实、虚构 fixed 、 movable real 、 imaginary

00 3. Types of systems热力系统分类 (1)In terms of the interaction between system and its surroundings 依据系统和外界之间的相互作用 es No Mass open closed Heat non-adiabatic adiabatic Work with work without work Mass. heat or work non-isolated isolated www.themegallery.com Company Logo

www.themegallery.com Company Logo (1)In terms of the interaction between system and its surroundings 依据系统和外界之间的相互作用 Yes No Mass ? open closed Heat ? non-adiabatic adiabatic Work ? with work without work Mass, heat or work ? non-isolated isolated 3. Types of systems 热力系统分类

A Closed system and open system 闭口系统和开口系统 A Closed systen( a control mass控制质量) consists of a fixed amount of mass, and no mass can cross its boundary That is, no mass enters or leave a closed system 闭口系与外界无物质交换 such as Piston- cylinder device(汽缸-活塞装置) An Open system( or a control volume控制体积)isa roperly selected region in space. Both mass and energy, can cross the boundary of a control volume. 开口系写外界有物质交换 such as, A Water heater a turbine and a compressor etc www.themegallery.com Company Logo

www.themegallery.com Company Logo A Closed system (a control mass 控制质量) consists of a fixed amount of mass, and no mass can cross its boundary. That is, no mass enters or leave a closed system. 闭口系与外界无物质交换 such as, Piston-cylinder device (汽缸-活塞装置） An Open system (or a control volume 控制体积）is a properly selected region in space. Both mass and energy can cross the boundary of a control volume. 开口系与外界有物质交换 such as, A Water heater, a turbine and a compressor, etc A. Closed system and Open system 闭口系统和开口系统