A modified electrical conductivity model for insulating oil-based nanofluids

A new kind of nanofluids based on insulating oil was prepared with ZnO nanoparticles synthesized by solvothermal reaction, aiming at enhancing both the dielectric and thermal characteristics of insulating oil. A linear dependence of the effective electrical conductivity on volumetric fraction has been observed, and the electrical conductivity shows an exponential growth with temperature. To interpret the electrical conductivity mechanism, a modified model is introduced based on Maxwell electrical conductivity equation and electrophoresis phenomenon, and compared with the experimental results.