A comprehensive experimental study on thermal conductivity of ZrO2-SiC /DW hybrid nanofluid for practical applications: Characterization, preparation, stability, and developing a new correlation

Abstract

This study mainly intended to identify changes in the thermal conductivity of distilled water (DW) because of the addition of Zirconium oxide (ZrO2) and Silicon carbide (SiC) nanoparticles. Keeping this in view, the study considered hybrid nanofluid samples developed with the help of ZrO2 (dp: 20 nm)-SiC (dp: 45––60 nm) nanoparticles. Initially, the research involved conducting XRD, TEM, EDX and FESEM tests which allowed for conducting phase and structural analysis and also facilitated the study of nanoparticles’ microstructure. In the next step, a magnetic stirrer and ultrasonic vibrator were used in sequential steps for dispersing and homogenizing Nanomaterials in distilled water. The volume concentration (φ) was kept between 0.025 and 0.1 % during the synthesis of samples. Then the samples were checked to evaluate their thermal conductivity through the transient hot wire method. In this way, the thermal conductivity of all samples was evaluated for temperatures between 20 and 60 °C. The results indicated a positive association of the thermal conductivity of nanofluid with parameters like temperature and solid volume fraction. It was noted that ZrO2-SiC/DW hybrid nanofluid depicted a nearly 25.75 % increase in thermal conductivity at a 0.1 % volume fraction of nanoparticles and a temperature of 60 °C. The value of the thermal conductivity ratio of ZrO2-SiC/DW was determined using the proposed mathematical correlation. The fitting method was applied to experimental data which depicted the R-Square value of 0.9906 which is considerably high. It was found that the proposed equation gave an acceptable value of the maximum margin of deviation (i.e.,1.15 %).