heat engine

简明释义

热力发动机

英英释义

例句

1.Steam turbines are a common type of heat engine used in power plants.

蒸汽涡轮是电厂中常用的一种热机。

2.The heat engine in your refrigerator works in reverse to cool the interior.

你冰箱里的热机反向工作以冷却内部。

3.In thermodynamics, the Carnot cycle describes an ideal heat engine.

在热力学中，卡诺循环描述了一种理想的热机。

4.A car operates using a heat engine, which converts fuel into mechanical energy.

一辆汽车使用热机运作，将燃料转化为机械能。

5.The efficiency of a heat engine can be improved by increasing the temperature difference.

通过增加温差，可以提高热机的效率。

作文

A heat engine is a fascinating device that converts thermal energy into mechanical work. This process is essential in various applications, from powering vehicles to generating electricity in power plants. Understanding the principles behind a heat engine can provide insights into both the efficiency of energy conversion and the fundamental laws of thermodynamics.The basic operation of a heat engine involves two heat reservoirs: a hot reservoir and a cold reservoir. The heat engine absorbs heat from the hot reservoir, performs work, and then expels some heat to the cold reservoir. The efficiency of a heat engine is defined as the ratio of the work output to the heat input from the hot reservoir. This efficiency is often limited by the second law of thermodynamics, which states that not all absorbed heat can be converted into work.One of the most common examples of a heat engine is the internal combustion engine found in most cars. In this type of engine, fuel is burned in a combustion chamber, producing hot gases that expand and push against pistons. This mechanical movement is then translated into the motion of the vehicle. The efficiency of internal combustion engines typically ranges between 20% to 30%, meaning that a significant amount of energy is lost as waste heat.Another example is the steam engine, which was pivotal during the Industrial Revolution. In a steam engine, water is heated to produce steam, which expands and drives a piston or turbine. This type of heat engine played a crucial role in the development of railways and factories, marking a significant shift in how work was performed.The theoretical maximum efficiency of a heat engine is described by the Carnot efficiency, which is determined by the temperatures of the hot and cold reservoirs. According to the Carnot theorem, no heat engine operating between two heat reservoirs can be more efficient than a Carnot engine, which operates reversibly. This theoretical model sets an upper limit on the efficiency of real-world engines, highlighting the importance of temperature differentials in energy conversion.Modern advancements in technology have led to the development of more efficient heat engines. For instance, combined cycle power plants utilize both gas and steam turbines to maximize energy extraction from fuel. By using the waste heat from the gas turbine to generate steam for the steam turbine, these plants can achieve efficiencies exceeding 60%. Such innovations are crucial in addressing global energy demands while minimizing environmental impact.In conclusion, a heat engine is a vital component of modern engineering and technology. Its ability to transform thermal energy into mechanical work is foundational to many industries and everyday applications. As we continue to innovate and improve the efficiency of these engines, we move closer to sustainable energy solutions that can meet the needs of our growing population. Understanding the mechanics and limitations of heat engines not only enhances our appreciation for these machines but also guides future developments in energy technology.

热机是一种迷人的装置，它将热能转化为机械功。这一过程在各种应用中至关重要，从驱动车辆到在发电厂中发电。理解热机背后的原理可以提供对能量转换效率和热力学基本定律的深入了解。热机的基本操作涉及两个热库：热库和冷库。热机从热库吸收热量，执行工作，然后将一些热量排放到冷库。热机的效率定义为输出功与来自热库的热输入之比。这种效率通常受到热力学第二定律的限制，该定律指出，并非所有吸收的热量都可以转化为功。热机最常见的例子之一是大多数汽车中的内燃机。在这种类型的发动机中，燃料在燃烧室中燃烧，产生的热气体膨胀并推动活塞。这种机械运动随后被转化为车辆的运动。内燃机的效率通常在20%到30%之间，这意味着相当大一部分能量作为废热损失。另一个例子是蒸汽机，它在工业革命期间发挥了关键作用。在蒸汽机中，水被加热以产生蒸汽，蒸汽膨胀并驱动活塞或涡轮。这种类型的热机在铁路和工厂的发展中发挥了至关重要的作用，标志着工作方式的重大转变。热机的理论最大效率由卡诺效率描述，卡诺效率取决于热库和冷库的温度。根据卡诺定理，在两个热库之间运行的热机的效率不能高于卡诺热机，该热机以可逆方式运行。这个理论模型为现实世界发动机的效率设定了上限，突显了温差在能量转换中的重要性。现代技术的进步导致了更高效的热机的发展。例如，联合循环发电厂利用燃气涡轮和蒸汽涡轮来最大化从燃料中提取的能量。通过利用燃气涡轮的废热来生成蒸汽供蒸汽涡轮使用，这些发电厂的效率超过60%。这样的创新在应对全球能源需求的同时，最小化环境影响方面至关重要。总之，热机是现代工程和技术的重要组成部分。它将热能转化为机械功的能力是许多行业和日常应用的基础。随着我们不断创新和提高这些发动机的效率，我们离满足日益增长的人口需求的可持续能源解决方案又近了一步。理解热机的机制和局限性不仅增强了我们对这些机器的欣赏，也指导了未来能源技术的发展。