考虑循环水-能源桩换热的单U型埋管能源桩变热流传热模型  

Heat Transfer Model of a Single U-tube Energy Pile With Variable Heat Flow Considering Heat Exchange Between Circulating Water and Energy Pile

作　　者：席省麟 时刚[1] 魏子贺 XI Shenglin;SHI Gang;WEI Zihe(School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China)

机构地区：[1]郑州大学土木工程学院,郑州450001

出　　处：《工程热物理学报》2023年第6期1709-1719,共11页Journal of Engineering Thermophysics

基　　金：2022年度河南省重点研发与推广专项(科技公关)项目(No.222102320118)。

摘　　要：基于有限长度线热源模型和叠加原理,提出了一种变热流条件下有限长度线热源模型的近似解答;在此基础上,将单U型换热器划分为多个节段,采用热响应的分段叠加思路,最终建立了考虑循环水与能源桩换热的单桩变热源传热模型。通过与Comsol三维数值模型和无限长线热源模型出水口温度的比较以及与试验中出水口温度和土体温度的比较,验证了该模型的准确性。同时通过该传热模型进行了U形管能源桩不同桩长、不同质量流率、不同桩土导热系数的换热分析。此模型可以帮助我们获得随时间变化的热流密度和更为精确的出水口温度,便于能源桩换热量的快速评估。Based on the finite line heat source model and superposition principle,an approximate solution of the finite line heat source model under the condition of variable heat flow is proposed in this paper;On this basis,the single U-tube heat exchanger is divided into multiple sections and the idea of piecewise superposition of thermal response is adopted.In order to account for the heat exchange between the energy pile and the circulating water,a single pile variable heat flow model is developed.By comparing the outlet temperature with COMSOL three-dimensional numerical model and infinite line heat source model,and comparing it with the outlet temperature and the soil temperature in the test,the accuracy of the model is verified.Simultaneously,the heat transfer analysis of a U-tube energy pile with different pile lengths,mass flow rates,and thermal conductivity of pile-soil was performed using this heat transfer model.This model can help us to obtain the timevarying heat flux and more accurate outlet temperature,to quickly assess the energy pile's heat exchange rate.

关 键 词：能源桩 变热源传热模型 分段叠加法 传热效率 

分 类 号：TK123[动力工程及工程热物理—工程热物理]