河网中的非衡相变.pdf

宁夏大学硕士学位论文摘要
摘要
本文主要就河流网的演化,河道形态的变迁,河网上水沙流动的动力学,运用非平衡统计力
学的原理、思想和方法进行尝试性研究,以期对河网演化的机制获得新认识。特别地,从最小能
耗率原理、非平衡相变及耗散结构理论等非平衡态理论的角度出发,揭示河型形成及转化的机制,
并在前期对河流网泥沙输移动力学模型研究的基础上,建立了新的河流网泥沙输运动力学模型。
最后,对河流系统的最大广义流做了解析讨论。本文的主要工作如下:
(1)简要概述非平衡态统计理论,特别是结合河流系统的特性,对最小能耗率原理、非平衡
相变及耗散结构理论作了较为详细的阐述,为相关领域研究提供新的研究方法和视角。
(2)运用最小能耗率原理、非平衡相变及耗散结构理论分析河型成因及转化,表明河型转化
过程中存在双临界。同时,结合实际河流的水文数据统计结果进一步说明河网发展演化的自调节
机制。
(3)在不考虑支流汇流的情况下,建议一个基于水流携沙力受河道冲淤态反馈调节的泥沙输
移模型,模拟结果能够展示双临界现象,并由此分析河型的形成和转化机制。最后,通过对最大
广义流的解析给出不同河型的判断指标及其转化的选择法则,从而对今后的科研工作以及实际工
程问题提供一定的参考。
本文的结尾部分,是全文的总结,并对所做的工作作了展望。
关键词:河型转化,耗散结构,泥沙输移动力学模型,最大广义流






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宁夏大学硕士学位论文 Abstract

Abstract
This thesis mainly attempts to conduct a research on the evolution of works, the transition
of river pattern, and the dynamics of sediment flow in works. With the principle of non-
equilibrium statistical mechanics, ideas and methods, we try to get new understandings to the evolution
mechanism of , from the viewpoint of the theories of minimum rate of energy
dissipation, non-equilibrium phase transition and dissipative structure, it revealed the mechanisms of
river-type formation and transformation. Based on the research of preliminary dynamic models for
sedment transport in work, a new dynamic model for sedment transport on work is
, this thesis did a numerical analysis for the maximum generalized flux of the river
systems. The main works presented in this thesis are listed as follows:
(1) We briefly overviewed of the non-equilibrium statistical theory, bination with
the characteristics of river systems, detailedly introduced the theories of minimum rate of energy
dissipation, non-equilibrium phase transition and dissipative structure theory. It provided new research
methods and perspective for related field study.
(2) Using theories of minimum rate of energy, non-equilibrium phase transition and dissipative
structure,we analyzed the causes and tr