| The excellent performance and efficiency of modern gas turbine needs advanced cooling schemes to protect the hot components of engine from the high temperature environment. As a new cooling method, pre-swirl nozzles were used to supply the cooling air to the turbine blades which swirl in the rotate direction of the turbine disk, so it could be reduced the total temperature of the cooling air relative to the blades. Up to now, the research about it is not mature enough due to its complication. It is make sence to do systematical and deeply studies.Both numerical computation and experiments were used to study systemic about the effects of the different radial positions of pre-swirl nozzles on the heat transfer in the rotor-stator cavity. Firstly, six radial positions of nozzles have been numerical studied by the use of FLUENT software, and according to the results of computation, stators were designed and made which contains four radial positions's pre-swirl nozzles and will be used in the experiments. Then the experiments were taken to obtain the heat transfer law in the cavity under various nozzles's radial positions, gap between the rotor and the stator, mass flow rates and the rotation speeds of the rotor.The experiments results indicated that: 1) the nondimensional total temperature difference is monotone decreased with the increase of rotational Reynolds number, and the change of rotor's local Nusselt number is related to the radial position of the pre-swirl nozzles; 2) under certain radial position of pre-swirl nozzles, the change of nondimensional total temperature difference and local Nusselt number with the rotational Reynolds number is not effected by the mass flow rates; 3) the nondimensional total temperature difference is increased firstly and then diminished with the increase of swirl ratio; 4) the integration of cooling effects is best when the pre-swirl nozzles be in middle part of cavity in the radial direction.
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