应用物理—热力学函数图式运算法.pdf

Applied Physics 应用物理, 2012, 2, 77-81 doi:10.4236/app.2012.23013 Published Online July 2012 (/journal/app) Graphic Algorithm of the Thermodynamic Functions Junxiang Chen National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, CAEP, Mianyang Email: cjx621@163.com Received: Apr. 25th, 2012; revised: May 7th, 2012; accepted: May 10th, 2012 Abstract: A graphic algorithm for the derivation of the characteristic thermodynamic functions has been presented. The relation between the functions and variables are arranged in graphics according to the following three rules. 1) The dif- ference of two neighboring functions is equal to the product of the two conjugate variables which link the two functions; 2) The differential of a function is equal to its characteristic variable differential multiplied by its conjugate coefficient; 3) The partial derivative formed by three variables arranged sequentially along the inner circle is equal to its counterpart formed by another three variables by using reverse arrangement rule. This algorithm is intelligible, operation convenient and easy to grasp, which proves to be beneficial for the teaching and studying. Keywords: Characteristic Function; Total Differential; Partial Derivative 热力学函数图式运算法 陈俊祥 中国工程物理研究院流体物理研究所冲击波物理与爆轰物理国防科技重点实验室，绵阳 Email: cjx621@163.com 收稿日期：2012 年 4 月 25 日；修回日期：2012 年 5 月 7 日；录用日期：2012 年 5 月 10 日 摘 要：本文提出了一种热力学函数图式运算方法，这种方法把函数和变量的关系按照三种运算规则排列成图 形：1) 相邻两函数之差等于连接这两个函数的共轭变量之积；2) 一个函数的微分等于它的两个特征变量的微分 乘其共轭系数之和；3) 函数图内圈上每三个变量组成的偏导数等于按反转规则运行的另外三个变量组成的偏导 数。运算规则安排巧妙，操作方便，容易掌握。可供教学和科研工作者使用。 关键词：特性函数；全微分；偏导数 1. 引言