The three-dimensional numerical simulations of heat transfer in a rotor-stator cavity with pre-swirl nozzles at different radial positions in the stator were conducted in this paper.The standard k-ε turbulence model and unstructured grid were applied with the purpose of investigating the heat transfer characteristics.Under the constant mass flow rate and the different radial position of the pre-swirl nozzles

the outflow temperature and the effect of heat transfer on the rotor are greatly affected by the different rotational Reynolds number

pre-swirl angle and rotor-stator gap.The results show that the heat transfer of the rotor is enhanced with the increase of the rotational Reynolds number or the decrease of the rotor-stator gap.When the pre-swirl nozzles were moved out along the radial direction

the temperature difference between the inlet and the outlet and the averaged Nusselt number take on up-down tendency

that is

exists a optimum radial position of the pre-swirl nozzles.