基于熵指标的热能传输动态特性建模与仿真分析

Modeling and Simulation Analysis of Heat Transfer Dynamic Characteristics Based on Entropy Index

为研究集中供热管网的物理特性和动态热力特性,以熵的输运为基础,基于传热规律和热力学定律提出温度-广义熵流模型。类比经典电路分析理论,以温度为强度量,熵流为广延量,建立热能传输的分布参数电路等值模型和集中参数模型,对热能传输过程中的损耗和时延特性进行精确建模。所得模型通过与热路供热流动的偏微分方程求解结果进行对比,验证了模型的正确性。另外,利用能量守恒定律和熵的不守恒原理,以熵为标度,提出热网中管道和节点处可用热功率及其损失的计算方法,衡量热网中热能传输过程中能量的数量与品质,可直观展示热网中热能可用功率的变化情况。

To study the physical and dynamic thermodynamic characteristics of the central heating pipe network,this paper proposes a temperature-generalized entropy flow model based on entropy transport and heat transfer law and thermodynamic law.Through analogy with classical circuit analysis theory,the equivalent model and lumped parameter model of distributed parameter circuit for heat transfer are established with temperature as intensity and entropy flow as an extension.These models are used to accurately model the loss and delay characteristics in the process of heat energy transmission.The correctness of the model is verified by comparing the obtained model with the solution results of the partial differential equation of the heat supply flow.In addition,the law of conservation of energy and the non-conservation principle of entropy are used.Taking entropy as the scale,the calculation method of available heat power and its loss at pipes and nodes in the heat network is proposed to measure the quantity and quality of energy in the heat energy transmission process in the heat network,as well as intuitively display the change of available heat power in the heat energy network.