heat engine

简明释义

热机

英英释义

例句

1.The efficiency of a heat engine can be calculated using the Carnot theorem.

可以使用卡诺定理计算热机的效率。

2.In power plants, large heat engines generate electricity by burning coal or natural gas.

在发电厂，大型热机通过燃烧煤或天然气来发电。

3.A car operates using a gasoline-powered heat engine, which converts fuel into mechanical energy.

一辆汽车使用汽油驱动的热机，将燃料转换为机械能。

4.The heat engine in a steam locomotive uses steam to drive pistons.

蒸汽机车中的热机利用蒸汽驱动活塞。

5.Refrigerators work on the principle of a reversed heat engine.

冰箱的工作原理是反向的热机。

作文

A heat engine is a fundamental concept in thermodynamics that plays a crucial role in our daily lives. It refers to a device that converts thermal energy into mechanical work by utilizing the temperature difference between two heat reservoirs. The basic principle behind a heat engine is the conversion of heat energy, usually derived from combustion or other forms of thermal energy, into usable mechanical energy. This process is essential for various applications, including power generation, transportation, and industrial operations.The operation of a heat engine can be explained through the four main processes it undergoes: isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression. During the isothermal expansion phase, the working substance absorbs heat from a high-temperature reservoir, causing it to expand and perform work on the surroundings. Next, in the adiabatic expansion phase, the working substance continues to expand without exchanging heat with its environment, leading to a drop in temperature.Following this, the heat engine enters the isothermal compression phase, where it releases heat to a low-temperature reservoir while being compressed. This process allows the working substance to return to its initial state, ready to begin the cycle again. Finally, during the adiabatic compression phase, the working substance is compressed further without heat exchange, increasing its temperature and pressure.One of the most well-known examples of a heat engine is the internal combustion engine found in automobiles. In this type of engine, fuel is burned to produce hot gases, which then expand and push the pistons, converting chemical energy into mechanical work. This process is not only efficient but also highlights the importance of heat engines in modern transportation.Another example is the steam engine, which played a pivotal role during the Industrial Revolution. The steam engine operates on the principle of converting heat energy from boiling water into mechanical work. By heating water in a boiler, steam is generated, which then expands and pushes a piston or drives a turbine. The steam engine significantly increased productivity and transformed industries, making it an iconic representation of heat engines in history.Despite their various applications, heat engines are subject to limitations defined by the laws of thermodynamics. The second law states that no heat engine can be 100% efficient because some energy is always lost as waste heat. This inefficiency has led to ongoing research and development aimed at improving the performance of heat engines. Innovations such as combined cycle power plants, which utilize both gas and steam turbines, have emerged to enhance efficiency and reduce environmental impact.In conclusion, understanding the concept of a heat engine is essential for grasping the principles of energy conversion and thermodynamics. These engines are integral to many technologies that drive our society forward, from vehicles to power plants. As we continue to seek more sustainable energy solutions, the study of heat engines will remain a vital area of research, ensuring that we can harness thermal energy efficiently and responsibly for future generations.

热机是热力学中的一个基本概念，在我们的日常生活中发挥着至关重要的作用。它指的是一种将热能转化为机械功的装置，利用两个热库之间的温差。热机的基本原理是将热能（通常来源于燃烧或其他形式的热能）转化为可用的机械能。这一过程对于电力生成、交通运输和工业操作等各种应用至关重要。热机的运行可以通过它经历的四个主要过程来解释：等温膨胀、绝热膨胀、等温压缩和绝热压缩。在等温膨胀阶段，工作物质从高温热库中吸收热量，导致其膨胀并对周围环境做功。接下来，在绝热膨胀阶段，工作物质在不与环境交换热量的情况下继续膨胀，导致温度下降。随后，热机进入等温压缩阶段，在此阶段，它向低温热库释放热量，同时被压缩。这个过程使工作物质能够返回到初始状态，准备再次开始循环。最后，在绝热压缩阶段，工作物质在没有热量交换的情况下被进一步压缩，导致温度和压力升高。最著名的热机之一是汽车中的内燃机。在这种类型的发动机中，燃料被燃烧以产生热气体，这些气体扩展并推动活塞，将化学能转化为机械功。这个过程不仅高效，而且突显了热机在现代交通中的重要性。另一个例子是蒸汽机，在工业革命期间发挥了关键作用。蒸汽机的工作原理是将沸水的热能转化为机械功。通过在锅炉中加热水，产生蒸汽，然后扩展并推动活塞或驱动涡轮。蒸汽机显著提高了生产力，并改变了工业，使其成为热机历史上一个标志性的代表。尽管热机有各种应用，但它们受到热力学定律所定义的限制。第二定律指出，没有热机可以达到100%的效率，因为总会有一些能量作为废热损失。这种低效率促使人们不断进行研究和开发，以提高热机的性能。诸如联合循环发电厂等创新，利用燃气和蒸汽涡轮，已经出现，以提高效率并减少环境影响。总之，理解热机的概念对于掌握能量转化和热力学的原理至关重要。这些发动机是推动我们社会前进的许多技术的核心，从车辆到发电厂。随着我们继续寻求更可持续的能源解决方案，热机的研究将仍然是一个重要的研究领域，确保我们能够高效和负责任地利用热能，为未来的世代服务。