狭缝内受限流体自发对称破缺过程的熵减热力学特性研究  

Study on the thermodynamic characteristics of entropy decrease in the spontaneous symmetry breaking process of confined fluids in the slit

作　　者：郑丹菁 李玉秀 郑佳杰 孔令辉 谢驰 陈颖 ZHENG Danjing;LI Yuxiu;ZHENG Jiajie;KONG Linghui;XIE Chi;CHEN Ying(School of Materials and Energy,Guangdong University of Technology,Guangzhou 510006,Guangdong,China)

机构地区：[1]广东工业大学材料与能源学院,广东广州510006

出　　处：《能源化工》2025年第1期33-41,共9页Energy Chemical Industry

基　　金：国家自然科学基金项目(51776043);国家自然科学基金区域创新项目(U20A20299)。

摘　　要：系统自发对称破缺的发生会令相空间体积收缩、系统熵减少,熵减的热力学特性蕴含对外做功的能力在探明微纳尺度能量传输路径方面具有重要的应用价值和理论研究意义。以狭缝内受限流体为工作介质,构建由上下固体板和狭缝内流体组成的热力学系统,采用理论分析与数值模拟相结合的手段,验证了狭缝内受限流体在发生自发对称破缺的过程中具备熵减的热力学特性。首先从相空间的角度出发,对狭缝内受限流体自发对称破缺过程进行理论分析,获得系统熵变与正向演化概率之间的定性关系,证明了当正向演化概率小于1时,系统熵减;再利用分子动力学模拟手段,构建了以金属钠为上下固体板的狭缝内受限液氩热力学模型,通过对自发对称破缺过程所需外功大小与自由能变化的比较,定量获得了在给定初末密度分布状态时熵的变化。该研究拓宽了狭缝内受限流体模型的应用领域,其所具备的对外做功的能力也为新型热机的研究提供了新的思路。The spontaneous occurrence of symmetry breaking within a system leads to a contraction in phase space volume,resulting in a decrease in system entropy.The thermodynamic characteristic of entropy decrease implies the ability to perform work externally,holding significant application value and theoretical research significance in exploring energy transfer pathways at the micronano scale.This article focuses on confined fluids within slits as the working medium,constructing a thermodynamic system composed of upper and lower solid plates and the fluid within the slits.By combining theoretical analysis with numerical simulation,the study verifies the thermodynamic characteristic of entropy decrease in confined fluids during the process of spontaneous symmetry breaking.Firstly,from the perspective of phase space,a theoretical analysis is conducted on the spontaneous symmetry breaking process of confined fluids in narrow slits,and a qualitative relationship between system entropy change and forward evolution probability is obtained.It is proved that when the forward evolution probability is less than 1,the system entropy decreases.By utilizing molecular dynamics simulation techniques,a thermodynamic model of confined liquid argon in a narrow slit with metallic sodium as the upper and lower solid plates is constructed.By comparing the external work required for spontaneous symmetry breaking process with the change in free energy,the entropy change at a given initial and final density distribution state is quantitatively obtained.This research broadens the application scope of confined fluid models and the ability to perform external work,providing new insights for the study of novel heat engines。

关 键 词：受限流体 自发对称破缺 熵减 相空间 分子动力学模拟 

分 类 号：O552.4[理学—热学与物质分子运动论]