河流最小可用能耗率原理和统计熵理论研究

Research on the theory of minimum rate of available energy dissipation and statistic entropy in rivers

河流是一个具有能量紊动粘性热耗散结构的开放系统 ,依照热力学熵差和统计熵定义了河流水力熵差和统计熵 ,根据耗散结构动平衡稳定的熵和能耗理论 ,建立明渠流和冲积河流的水力熵和统计熵理论 ,提出了明渠流和冲积河流稳定的最小可用能耗率原理和公式 ,该原理全面地反映了河道输水输沙的能耗特性 ,不仅在数学上完整地表达了冲积河流河床演变的基本原理———自动调整作用原理 ,而且还反映了床沙质和冲泻质的划分标准、高含沙水流和挟沙力等特性 ,并用该理论解释了冲积河流水沙运动和河床演变的各种现象。

A river is an open system with structure of thermodynamic energy dissipation by turbulence and viscosity. According to the thermodynamic entropy and statistic entropy, the authors defined hydraulic entropy and statistic entropy of rivers. Based on the theory of entropy and energy dissipation about dynamic equilibrium stability of irreversible process in open system of dissipation structure, theory of hydraulic entropy and statistic entropy in open channel and fluvial river was set up, and the principle and formula of minimum rate of available energy dissipation were put forward. This theory thoroughly represents the characteristics of energy dissipation in transporting water and sediment, and the formula of the theory perfectly expresses the basic theory of self-regulation of riverbed deformation in fluvial rivers. Various phenomena in fluvial rivers such as riverbed deformation, flow movement, and sediment transport were explained with this theory.