PowerPoint Template-精选.ppt

Generalized Representation of Heat Engines （热机工作原理的示意） 热 源 (Heat source) 冷 源 (heat sink) Company Logo * How many W can be produced by absorbing QH? Is there any relationship between QH,QL and W? Is QL necessarily to be discharged to its surroundings, becoming waste energy? Company Logo * (2) Internal combustion engine 内燃机装置 Company Logo * Mixture of air and fuel (空气、油) Waste gases 废气 吸气 Charging stroke 压缩、点火 Compress and Ignite 膨胀 expand 排气 Discharging stroke Company Logo * Characteristics of internal combustion engines 内燃机装置基本特点 (1) heat source (热源) (2) working medium 工质（燃气） (3) State changes of the working medium (工质经历状态变化) (加压、加热、 膨胀做功、放热) (4) heat sink (冷源) Company Logo * 冰箱 (Refrigerator) (3)制冷空调装置 Refrigeration System Company Logo * Characteristics of Refrigeration System 制冷空调装置的特点 cold source 冷源 (2) Working medium 工质（制冷剂） (3) State changes 工质的状态变化 (加压消耗外界的功量、放热、 膨胀、吸热) (4) Heat source热源 Company Logo * Heat source at high temperature （高温热源 hot reservoir） Working substance or working medium （工作介质） C. The change in state of working medium （工质的 状态变化） D. Heat sink at low temperature （低温冷源 cold reservoir） Thermal energy reservoirs: heat source heat sink (4) Main Factors in energy transformation (能量转换中的主要因素) Company Logo * ? What are the Main Contents of Engineering Thermodynamics? Company Logo * §0.2 Main Contents 主要内容 1. Basic Principles of Thermodynamics 能量转换的基本定律 (1) The first law of thermodynamics (conservation of energy principle) 热力学第一定律 （能量守恒原理） For example: a rock falling off a cliff human body It asserts that energy is a kind of thermodynamic property of substance. 阐明能量是物质的一种热力学属性. Company Logo * It asserts that energy has quantity as