Abstract: With the development of technology,the integration of electric equipment is increasing greatly,and the new and high effective cooling methods are paid more and more attention.Experiments and 3D numerical simulations have been performed to investigate a new cooling method,which employs the thermal driving of fluid in small size circular enclosures to enhance heat transfer rate.A clear view of the fluid flow was kinescoped in the experiments and numerical simulations were applied to investigating the details of flow and heat transfer in the enclosure.The simulation result agrees well with that of the experiment.All results show that this new cooling scheme will have a good future if applied to the high efficient electronic cooling equipment.