Thermal and Dielectric Analysis of an Ester-Based MgO Nanofluid

Magnesium oxide (MgO) nanoparticles (NPs) are used for nanofluid preparation in an effort to investigate their dielectric response and thermal properties. The matrix oil for the prepared samples is natural ester oil. Lightning impulse voltage (1.2/
$50~\mu \text{s}$
) is used to investigate the electrical performance of the different concentration samples. In addition, broadband dielectric spectroscopy is used for the analysis of the dielectric constant and electrical conductivity through a temperature range of 30 °C–90 °C and a frequency spectrum of 0.1 Hz–1 MHz. Thermal properties are studied by means of laser flash analysis and differential scanning calorimetry. Thermal conductivity is calculated, and the understudied results are evaluated. Results reveal an improvement in different properties for the prepared nanofluid samples, including an enhancement by 15.15% and 12.63% of the lightning impulse breakdown voltage and the thermal conductivity, respectively.