Abstract

Experimental study of convective heat transfer behavior and the AC dielectric breakdown voltage of nano oil for  use  in  transformers  is  the  main  scope  of  this  work.  The  nano  oil  containing  colloidal  magnetic  Fe3O4 nanoparticles  at  different  volume  concentration  and  the  Nytro  Libra  oil  that  is  the  conventional  oil  in  power transformers has been considered as the base  fluid.The convective  heat transfer behavior  was  studied by  using an experimental setup in laminar flow regime and under constant heat flux. The AC dielectric breakdown voltage by usingBA100 portable dielectric oil tester according to IEC 60156 was carried out. Results show thatnano oil with  23  nanometer  size  and  volume  concentration  of 0.1%  has  convective  heat  transfer  coefficient  to  4.5% higher  than  the  base  oil.  The  AC  dielectric  breakdown  voltage  improved  23.8%  for  nano  oil  with  volumeconcentration of 0.1% compared to the base oil. Theresults of the convective heat transfer coefficient behaviorof nano oil were compared with othe researchers