A new kind of nanofluids-based on transformer oil is prepared with ZnO nanoparticles synthesized by solvothermal reaction to investigate the influences of adding nanoparticles on electrical conductivity of Transformer oil. The mechanism how temperature and volumetric fraction affect electrical conductivity is also discussed. Then a modified model is introduced following Maxwell electrical conductivity equation and electrophoresis phenomenon. A linear dependence of the effective electrical conductivity on volumetric fraction is revealed
and the electrical conductivity exponentially heightens with temperature
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