Present paper deals with numerical simulation of flow in simplified model of the axial turbine stage equipped with the hub-seal. Main subject of simulations is study of various geometrical modifications of the outlet-slot from the hub-seal. The purpose of these modifications is to suppress a negative effect of complex secondary structures on the stage efficiency. Secondary flow structures are formed as a result of interaction of main stream above the outlet-slot with the leakage-stream from the hub-seal. It was found that suitable shape of the outlet-slot can bring up to six tenth of percent in efficiency.

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