理想气体热力学过程吸放热情况的图像判断法

如何简便地判断一个热力学过程的吸放热情况，对于了解此热力学过程是至关重要的．传统的方法是借助热力学第一定律，通过计算该热力学过程中的热学三量（功、热量和内能）来确定．文章通过分析简单热力学过程中的热容，得出：从绝热线上一点出发的微过程，过程曲线在绝热线下方，为放热过程；反之，为吸热过程．进一步，文章指出对于一些复杂的热力学过程，除使用传统的比较功大小的方法外，还可以利用热力学过程的末态相对等温线的位置而简单得出其吸放热情况。

A SIMPLE METHOD TO DETERMINE GAINING OR LOOSING HEAT IN A THERMODYNAMIC PROCESS FOR AN IDEAL GAS SYSTEM

How to easily determine the situation of gaining or loosing heat is very important for us to understand the thermodynamics process. Traditionally, one can do this by calculating and comparing three thermal quantities （work, heat, and the energy） of the thermodynamics process. In this paper, through simple analysis, we obtained the following results in terms of heat capacity of the thermodynamics process： The process which starts from a point on the adiabatic curve will be an exothermic one when it is at the bottom of the adiabatic curve, con- versely, it is an en traditional method the state, such as dothermic one. Moreover, for some complex processes, except for using the of comparing the size of the work, one can also take advantage of the end of the relative position of thermodynamic processes and simple isotherms, to obtain its endothermic heat conditions.