Abstract: Two real turbine disks are simplified to become a co rotating plan disk system.The effects of the coolant flow rate,rotational speed and the interval between the two discs on the performance of fluid flow and the heat transfer were investigated experimentally.Conclusions are drawn as follows:(1) the inlet Reynolds number could always have significant effects on average Nusselt number.(2) the rotational Reynolds number has little effect on averaged Nusselt number of the two disks.(3) the interval of two disks also has effect on averaged Nusselt number of the two disks.