化工学报2016，Vol.67Issue(12)：4936-4943,8.DOI:10.11949/j.issn.0438-1157.20160695
三角形微通道内纳米流体流动与换热特性
Characteristics of convective heat transfer in triangular microchannel heat sink using different nanofluids
摘要
Abstract
SiO2,Al2O3 and TiO2 nanofluids based on deionized water with a particle volume fraction of 0.1% were prepared by the two-step dispersion method. Surfactants were added into the nanofluids to reduce particle aggregation and enhance stability. An ultraviolet spectrophotometer was used to test the absorbance of nanofluids as the absorbance decreased with decreasing concentration of nanoparticles suspended in liquid. Based on the principle of transient plane source (TPS) method, the 2500S thermal constant analyzer was employed to conduct the thermal conductivity of nanofluids. In order to investigate the heat transfer performance in a triangular microchannel heat sink using nanofluids, an Infrared Thermal Camera (ImageIR 3350, Germany) was inverted and hanged immediately over the microchannel heat sink to observe the temperature distribution on the substrate. The condition of heat dissipation was imitated by a DC power supply (34420A, Agilent, China), which would energize to the thin film heater at a heat flux ofq= 200 W·cm−2. As different nanofluids were studied, DI-water was used to clean the experimental system after the previous experiment was done to avoid the residues of nanoparticles. The results reflected that the surfactants had effect on the absorbance of nanofluids, and the particles would aggregate with the increase of standing time. The thermal conductivity and convective heat transfer were improved by adding nanoparticles. The average temperature on substrate was cooled down, and the uniformity of temperature was also repaired. As the result, TiO2 nanofluids had a better behavior than SiO2and Al2O3 nanofluids.关键词
纳米粒子/稳定性/微通道/红外热像仪/传热Key words
nanoparticles/stability/microchannels/thermal infrared imager/heat transfer分类
能源科技引用本文复制引用
刘冉,夏国栋,杜墨..三角形微通道内纳米流体流动与换热特性[J].化工学报,2016,67(12):4936-4943,8.基金项目
北京市自然科学基金项目(3142004)。@@@@supported by the Natural Science Foundation of Beijing (3142004) （3142004）
