研究了一种能同时测量纳米流体导热系数λ、导温系数α和比热Cp的非稳态多功能测试新方法,它结合了单丝法准确测量导热系数和双丝法准确测量导温系数的优点.对几种液体的导热系数和导温系数的实测值与TPRC推荐值进行比较,最大偏差分别为-0.4％和-2.7％.导热系数和导温系数测试均方根误差分别<±0.5％和±3％.并用此法测量了纳米Al2O3流体和纳米TiO2流体的热物性参数,结果表明在流体中加入无机纳米粉体后其入和α较分散介质均有明显提高,加和原理不完全适用于纳米流体比热计算.
A new multifunctional method which integrates the transient hot-wire technique and hot-wire parallel
technique for determining the thermal conductivity and thermal diffusivity of abionanofluids was presented. The maximum deviation of thermal conductivity
and diffusivity between experimental results and TPRC-recommended values was --0.4% and --2.7% respectively. The accuracy of the measurement was estimated ±0.5% and ±3%
respectively. The experimental results showed that the thermal conductivity and the thermal diffusivity of nanofluids α-Al2O3 in ethylene glycol (EG) and TiO2 in water
were anomalously higher than those of EG and water. The heat capacity of nanofluids TiO2 in water was 10.4% higher than predicted.
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