深部矿井埋管充填体换热器蓄/释热过程中的热干扰问题  

Thermal interference of backfill heat exchangers in heat storage/releaseprocesses in deep mines

作　　者：张波 杨紫桐 刘浪[1] 赵玉娇[1] 郇超 王美[1] 屠冰冰[3] ZHANG Bo;YANG Zitong;LIU Lang;ZHAO Yujiao;HUAN Chao;WANG Mei;TU Bingbing(College of Energy Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;College of Architecture and Civil Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;College of Science,Xi’an University of Science and Technology,Xi’an 710054,China)

机构地区：[1]西安科技大学能源学院,陕西西安710054 [2]西安科技大学建筑与土木工程学院,陕西西安710054 [3]西安科技大学理学院,陕西西安710054

出　　处：《煤炭学报》2023年第3期1155-1168,共14页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(51874229);陕西省自然科学基础研究计划资助项目(2022JM-173);陕西省教育厅专项科学研究计划资助项目(21JK0766)。

摘　　要：矿床开采形成的丰富地下空间为太阳能等可再生能源的大规模存储提供了基本条件。将地埋管换热器置入矿井充填体中构建出具有蓄/释热功能的埋管充填体换热器是实现太阳能等可再生能源跨季节存储的新方法,但是热干扰问题会影响其蓄/释热性能而不容忽视。利用COMSOL仿真软件建立并验证了典型蛇形埋管充填体换热器的三维非稳态传热模型,通过管间热干扰系数(I_(tub))和层间热干扰系数(I_(lay))量化研究了管间距、管径、充填体导热系数和比热容对埋管充填体换热器的单层蛇形管管间和多层蛇形管层间热干扰影响,通过引入相对灵敏度参数讨论分析了管间和层间热干扰对研究参数的敏感度。结果分析表明,I_(tub)随蓄/释热时间呈先下降后上升的变化趋势,整体变化不大(0.92~1.00),说明单层蛇形管管间热干扰影响较小。I_(lay)呈单调显著递减,在蓄/释热阶段末分别低于0.25和0.49,说明多层蛇形埋管层间热干扰随着蓄/释热的进行严重恶化。通过灵敏度分析发现,I_(lay)对研究参数的敏感度明显高于I_(tub)。I_(lay)对充填体比热容、管间距、充填体导热系数和管内径的敏感度依次降低,其中充填体比热容和管间距为正面影响,另外2个为负面影响。I_(tub)在蓄/释热的大部分时间段对管间距最敏感。本研究量化了关键参数对埋管充填体换热器热干扰的影响,为优化蛇形埋管布置及充填材料制备以降低热干扰影响提供了依据。The abundant underground space created during the mining process of the deposits provides the basic conditions for the large-scale storage of renewable energy such as solar energy.A novel method of realizing seasonal storage of renewable energy,such as solar energy,is the construction of backfill heat exchangers(BFHEs)with a heat storage/release function by inserting ground heat exchangers into backfill bodies in mines.However,thermal interference issues can affect their storage/release performance and should not be overlooked.In this study,the COMSOL software was used to create a validated three-dimensional unsteady heat transfer model for a typical serpentine tube BFHEs,and the effects of tube spacing,tube diameter,backfill body’s thermal conductivity and specific heat were quantitatively investigated on the thermal interference of tube-to-tube and layer-to-layer of BFHEs using the thermal interference coefficient of tube-to-tube(I_(tub))and the thermal coefficient of layer-to-layer(I_(lay)),respectively.Additionally,the I_(tub)and I_(lay)’s sensitivities to the investigated parameters were discussed by reference to the relative sensitivity parameters.The findings indicate that the I_(tub)presents a decreasing and then increasing trend over time,but the overall change is small(0.92-1.00).This reflects that the thermal interference of tube-to-tube has a minor impact on single-layered serpentine BFHEs.The I_(lay)falls monotonically and considerably,and is lower than 0.25 and 0.49 at the end of heat storage/release processes,respectively.This means that the thermal interference of layer-to-layer deteriorates seriously with the heat storage/release for multi-layered serpentine BFHEs.The sensitivity analysis reveals that I_(lay)is noticeably more sensitive to the investigated parameters than I_(tub).The sensitivities of I_(lay)to specific heat,tube spacing,thermal conductivity and tube diameter decrease in descending order,with the first two parameters having positive effects and the latter two having negative e

关 键 词：热干扰 埋管充填体换热器 蓄/释热性能 季节性储能 蛇形埋管 

分 类 号：TD823.7[矿业工程—煤矿开采]