Aerodynamic investigation of the tip section for titanium blade 54″

Authors

M. Luxa, D. Šimurda - Institute of Thermomechanics AS CR, Czech Republic
J.Fořt, J.Fürst, P. Šafarík - Faculty of Mechanical Ingeneering, Czech Technical University in Prague, Czech Republic
J. Synác, B. Rudas - R&D dept., Doosan Skoda Power LTD., Czech Republic

Abstract

This paper presents an aerodynamic experimental and numerical investigation of the prismatic blade cascade that represents the tip section of a rotor comprising 52 titanium blades 1375mm in length. This rotor is designed for the last stage of the low pressure cylinder of a large output steam turbine. The flow conditions of the tip section are defined by the structural and operational demands in the last stage. The tip section is characterized by a supersonic inlet, a large stagger angle and a supersonic outlet. The profile applied to the tip section is relatively very thin, and its central line is unusually cambered, so the shapes of the suction and pressure sides have converse curvatures. The results of the aerodynamic experiments are compared with the results of numerical simulations calculated by both a commercial code and an in-house code.