太阳能供暖用新型流体制备及导热性能测试  

Experimental on Measurement of Thermal Conductivity of Phase Change Suspended Fluid by Transient Hot Wire Method

作　　者：张佳琦 齐典伟[1] 徐凤 李亚菲 ZHANG Jia-qi;QI Dian-wei;XU Feng;LI Ya-fei(College of Civil Engineering and Architecture,Xinjiang University,Urumqi 830046,China)

机构地区：[1]新疆大学建筑工程学院,乌鲁木齐830046

出　　处：《科学技术与工程》2023年第6期2573-2578,共6页Science Technology and Engineering

基　　金：新疆维吾尔自治区自然科学基金(2022D01C413)。

摘　　要：严寒、寒冷地区液体型集热器应用时需考虑防冻性能,工程常使用乙二醇型防冻液作为循环工质。但其导热系数仅为水的60%,集热循环过程中防冻液与太阳能集热器基板传热不充分导致基板过热和集热热损过大。为解决上述问题,通过乙二醇型防冻液及相变材料配制不同浓度的传热蓄热流体(heat transfer and heat storage fluid, HTHSF),在考虑防冻的基础上,以增加HTHSF综合导热系数为目的,通过瞬态热线法实验研究HTHSF相变过程中导热系数的变化规律。结果表明:当温度升高或浓度减小时载流体导热系数增大。配制的HTHSF呈水基溶液的特性,在单一相时导热系数与温度呈正比关系,相变使得导热系数有所减小。寒地太阳能供暖用新型HTHSF 10%、冰点-20℃时性能较好,此外拟合公式与实测数据误差在0.5%以内。Antifreeze performance should be considered in the application of liquid collector in cold and cold areas.Glycol antifreeze is often used as circulating working medium in engineering.However,its thermal conductivity is only 60%of water,and the insufficient heat transfer between the antifreeze and the solar collector base plate in the process of heat collection cycle leads to the overheating of the base plate and the excessive heat loss of the collector.In order to solve the above problems,heat transfer and heat storage fluid(HTHSF)with different concentrations are prepared by ethylene glycol antifreeze and phase change materials.On the basis of considering antifreeze,the comprehensive thermal conductivity of HTHSF was increased.The thermal conductivity of HTHSF during phase transformation was studied by transient hot wire method.The results show that the thermal conductivity increases when the temperature increases or the concentration decreases.The prepared HTHSF has the characteristics of water-based solution,and the thermal conductivity is proportional to the temperature when the phase is single,and the phase transformation makes the thermal conductivity decrease.The performance of the new HTHSF for solar heating in cold regions is better when the freezing point is-20℃,and the error between the fitting formula and the measured data is within 0.5%.

关 键 词：太阳能供暖 综合导热系数 瞬态热线法 热功能流体 

分 类 号：TU832[建筑科学—供热、供燃气、通风及空调工程] TK02[动力工程及工程热物理]