Specific Heat Measurement of Three Nanofluids and Development of New Correlations

This paper presents the specific heat measurements of three nanofluids containing aluminum oxide, zinc oxide, and silicon dioxide nanoparticles. The first two are dispersed in a base fluid of 60:40 by mass of ethylene glycol and water (60:40 EG/W) and the last one in deionized water. Measurements were conducted over a temperature range of 315-363 K, which is the normal range of operation of automobile coolants and building heating fluids in cold regions. The nanoparticle volumetric concentrations tested were up to 10%. The measured values were compared with existing equations for the specific heat of nanofluids. A close agreement with the experimental data was not observed. Therefore, a new general correlation was developed for the specific heat as functions of particle volumetric concentration, temperature, and the specific heat of both the particle and the base fluid from the present set of measurements. The correlation predicts the specific heat values of each nanofluid within an average error of about 2.7%.