Thermal conductivity of metal oxide nanofluids

Thermal conductivity;Nanofluids;Nanoparticles;Heat transfer

Beck, Michael Peter ; Chemical Engineering

University:Georgia Institute of Technology

Department:Chemical Engineering

关键词: Thermal conductivity;    Nanofluids;    Nanoparticles;    Heat transfer;   

Others  :  https://smartech.gatech.edu/bitstream/1853/26488/1/beck_michael_p_200812_phd.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

The thermal conductivities of nanofluids were measured as a function of temperature, particle size, and concentration.These nanofluids consisted of alumina, titania, or ceria dispersed in deionized water, ethylene glycol, or a mixture of the two.The results indicated that the temperature behavior of the thermal conductivity of the base fluid dominates that of the nanofluid.It was also discovered that decreasing nanoparticle size lowers the thermal conductivity of the nanofluid.None of the existing thermal conductivity models for heterogeneous materials was capable of predicting all of the observed relationships between thermal conductivity and temperature, particle size, volume fraction, and the thermal conductivities of the individual conductivities.Thus, a semi-empirical predictive model was proposed to predict the thermal conductivity of nanofluids.This model consists of the volume fraction-weighted geometric mean of the liquid and solid thermal conductivities where the solid conductivity is a function of particle size.The model provided predictions within 2.3 % of measured values in this work.