热电制冷液冷服内纳米流体自然循环换热特性  

Natural circulation heat transfer characteristics of nanofluid in thermoelectric refrigeration liquid cooling suits

作　　者：段炼[1] 韩吉田[1] 霍冲 曹琳琳 Duan Lian　;Han Jitian　;Huo Chong　;Cao Linlin(School of Energy and Power Engineering,Shandong University,Jinan 250061,China)

机构地区：[1]山东大学能源与动力工程学院,济南250061

出　　处：《东南大学学报（自然科学版）》2018年第2期220-225,共6页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51376110;51076084;41761144067)

摘　　要：对热电制冷液冷服内纳米流体自然循环的换热特性进行了实验研究.实验采用不同种类的、粒径在20~100 nm范围内的纳米流体,使其在填充有高孔隙率泡沫金属的换热器中被热电制冷元件降温,利用自然循环流动至与换热器连接的盘管中,在盘管中吸收热量,温度升高后再次进入换热器中冷却.将同样粒径和体积分数的Ti O2,Cu O,Cu等颗粒制成的纳米流体与去离子水在特定工况下进行对比实验,结果表明,采用纳米流体可显著增强循环的换热性能,其中Cu纳米流体的强化换热效果最好,制冷功率输出能力比同工况下的去离子水提升25%,系统最大制冷功率输出能力提升95%.针对不同尺寸和浓度的Ti O2纳米流体,研究了其粒径大小、体积分数等对循环过程的流动和换热产生的影响,结果表明,增大纳米颗粒的粒径和体积分数,在一定程度上可以增强其换热性能,但也会带来因团聚堆积增强而产生的堵塞和结冰等问题.The flow and heat transfer characteristics of nanofluids in a natural circulation loop for a personal cooling system based on thermoelectric cooler were experimentally studied.The nanofluids are prepared by suspending different kinds of nanoparticles with diameter ranging from 20 nm to 100 nm in the base fluid.In the experimental system,the nanofluid flowed into the heat exchanger filled with high porosity metal foam,and was cooled by a thermoelectric cooler.Then,the nanofluid flowed into the heat transfer coil by natural circulation and absorbed heat.The nanofluid flowed into the heat exchanger again to complete a natural circulation.The flow and heat transfer characteristics for nanofluids with deionized water as the base fluid and nanoparticles of TiO 2,CuO and Cu were experimentally determined compared with those of deionized water obtained by the experimental system under the identical conditions.The effects of particle sizes and volume fractions on the heat transfer characteristics was experimentally studied.Experimental results show that the heat transfer efficiency of nanofluid fluids is significantly enhanced compared with the deionized water.The result will contribute to the development and the practical operation of personal cooling systems.

关 键 词：纳米流体 自然循环 热电制冷 人体冷却 传热 纳米粒子 

分 类 号：TB663[一般工业技术—制冷工程]