基于非平衡态热力学和混沌理论的河型特性研究

发布时间：2018-04-17 02:10

本文选题：非平衡态热力学 + 混沌　；参考：《天津大学》2014年博士论文

【摘要】：本文以非平衡态热力学理论和混沌理论为基础,以冲积河流的河型为研究对象,以探寻不同河型的特性为目标,从宏观的角度对不同河型的特性进行了研究。主要研究内容包含以下方面:(1)提出一种河型判别式。借鉴社会与经济或环境与经济的协调发展理念,建立了河流系统的协调发展度判别式,用来判断冲积河流的河型。研究认为河流边界条件对河型的影响大于来水来沙条件;根据河流的协调发展度的大小判别河型。(2)基于非平衡态热力学理论中局域熵产生和能耗函数的关系,以及能耗函数可以写作不可逆过程的广义流和相应的广义力的乘积之和的形式,构造了河流的广义力和广义流,推导出河流的能耗函数的数学表达式,进而推导出河流的能耗率。(3)根据黄河下游花园口、夹河滩、高村、孙口、艾山、泺口和利津7个水文站的实测资料,计算了6个河段3种河型的单位水流功率和年份信息熵。研究表明,单位水流功率和年份信息熵越大的河型越不稳定,反之,单位水流功率和年份信息熵越小的河型越稳定。(4)提出一种河型稳定判别式。根据能耗率和熵产生的关系,以及超熵产生的定义,可以类推得到超能耗率。根据超能耗率推导出河型稳定判别式,并用该河型稳定判别式对黄河下游不同河型进行了稳定性分析。(5)对黄河下游6个河段的月径流序列和月含沙量序列进行了混沌特性分析。分析结果表明,由游荡河型到弯曲河型的转化,Lyapunov指数越来越大,即混沌特性越来越强,与此同时,吸引子不断演化形成巨大吸引子,即由混沌态到高级混沌态(耗散结构)。
[Abstract]:Based on the theory of nonequilibrium thermodynamics and chaos, this paper studies the characteristics of different river types from the macroscopic point of view, taking the river type of alluvial rivers as the research object and exploring the characteristics of different river types as the goal.The main research contents include the following aspects: 1) A river-type discriminant is proposed.Based on the idea of coordinated development of society and economy or environment and economy, the discriminant of coordinated development degree of river system is established, which is used to judge the river type of alluvial river.It is considered that the influence of river boundary conditions on river type is greater than that of incoming water and sediment conditions, and that the relationship between local entropy generation and energy consumption function is based on the relationship between local entropy generation and energy consumption function based on the degree of coordinated development of rivers.And the energy consumption function can write the sum of the generalized flow and the corresponding generalized force of irreversible process, construct the generalized force and generalized flow of the river, and derive the mathematical expression of the energy consumption function of the river.Based on the measured data of 7 hydrologic stations in Huayuankou, Jiahetan, Gaocun, Sunkou, Aishan, Luokou and Lijin in the lower reaches of the Yellow River, the unit flow power and year information entropy of three types of rivers in 6 reaches are calculated.The results show that the river type with greater unit flow power and year information entropy is more unstable, whereas the river pattern with smaller unit flow power and year information entropy is more stable. 4) A river type stability discriminant is proposed.According to the relation between energy consumption rate and entropy generation, and the definition of hyperentropy generation, the energy consumption rate can be deduced by analogy.Based on the excess energy consumption rate, the river stability discriminant is derived, and the chaotic characteristics of monthly runoff series and monthly sediment concentration series in 6 reaches of the lower Yellow River are analyzed by using the stability analysis of different river types in the lower reaches of the Yellow River.The results show that the transformation of Lyapunov exponent from wandering river type to curved river type is becoming larger and larger, that is, the chaotic property is becoming stronger and stronger, and at the same time, the attractor evolves into a huge attractor, that is, from chaotic state to higher chaotic state (dissipative structure).
【学位授予单位】：天津大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TV147

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