大学化学 >> 2026, Vol. 41 >> Issue (7): 401-405.doi: 10.12461/PKU.DXHX202506002

师生笔谈 上一篇    

范德华气体的节流膨胀与热力学函数的可视化

冯祥明, 郑金云, 曹若宇, 李丹, 关新新, 李朝辉, 陈卫华, 张建民   

  1. 郑州大学化学学院, 河南 郑州 450001
  • 收稿日期:2025-06-03 录用日期:2025-07-31 发布日期:2026-06-27
  • 通讯作者: 冯祥明 E-mail:fengxm@zzu.edu.cn Xiangming Feng
  • 基金资助:
    2024年度河南省高等教育教学改革研究与实践项目(2024SJGLX0035)

Visualization of throttling expansion and thermodynamic functions for Van der Waals gases

Xiangming Feng, Jinyun Zheng, Ruoyu Cao, Dan Li, Xinxin Guan, Zhaohui Li, Weihua Chen, Jianmin Zhang   

  1. College of Chemistry, Zhengzhou University, Zhengzhou 450001, Henan Province, China
  • Received:2025-06-03 Accepted:2025-07-31 Published:2026-06-27
  • Contact: Xiangming Feng E-mail:fengxm@zzu.edu.cn

摘要: 物理化学公式的可视化有助于学生对相关知识的理解和掌握,而相应数据处理软件的应用也使可视化过程更简单易行。为此,本文以节流膨胀为例,利用氮气的范德华方程、焦耳-汤姆逊系数计算公式分别绘制了氮气的pV-(p,T)、T-(p,T0)和μJ-T-(p,T)三维图像,以求在教学中更直观地讲解实际气体的节流膨胀效应。同时,借助μJ-T-(p,T)和V-(p,T)图像进一步展示了气体液化过程和等温条件下工程化求算范德华气体ΔH,ΔS和ΔG的方法。

关键词: 节流膨胀, 范德华气体方程, 焦耳-汤姆逊系数, 焓, 熵, 吉布斯自由能

Abstract: The visualization of physical chemistry formulas significantly enhances students’ comprehension and mastery of relevant concepts, while the application of appropriate data processing software simplifies the visualization process. This study employs nitrogen gas as an example, utilizing the Van der Waals equation and Joule-Thomson coefficient formula to construct three-dimensional representations of pV-(p,T), T-(p,T0), and μJ-T-(p,T) relationships. These visualizations facilitate more intuitive instruction regarding the throttling expansion effects in real gases. Furthermore, through the μJ-T-(p,T) and V-(p,T) plots, we demonstrate both the gas liquefaction process and engineering methods for calculating ΔH, ΔS, and ΔG of Van der Waals gases under isothermal conditions.

Key words: Throttling expansion, Van der Waals equation of state, Joule-Thomson coefficient, Enthalpy, Entropy, Gibbs free energy