Investigation of transonic and supersonic flow in the blade cascades representing rotor tip sections of the last lp steam turbine stage at different turbulence intensities

Authors

Marek Bobcik - Doosan Skoda Power, Ltd.
Jaroslav Fort - CTU Prague, Faculty of Mechanical Engineering
Jiri Furst - CTU Prague, Faculty of Mechanical Engineering
Jan Halama - CTU Prague, Faculty of Mechanical Engineering
Vladimir Hric - CTU Prague, Faculty of Mechanical Engineering
Petr Louda - CTU Prague, Faculty of Mechanical Engineering
Martin Luxa - Institute of Thermomechanics, CAS , v.v.i.
Bartolomej Rudas - Doosan Skoda Power, Ltd.
Jaroslav Synac - University of West Bohemia, Faculty of Mechanical Engineering
David Simurda - Institute of Thermomechanics, CAS , v.v.i.

Abstract

Design of a new generation of the large power steam turbines leads to very long last rotor blades with tip sections operating often in supersonic region. The flow field in such tip sections is not fully explored and it is believed to be fairly complex and very sensitive even on minute changes of flow parameters. This stimulated the study of the performance of profiles suitable for rotor tip sections. Numerical simulations have been carried out using TU Prague’s code based on the solution of the RANS equations and SST turbulence model by implicit finite volume method with AUSMPW+ scheme in high resolution formulation. Experimental data have been gathered in the intermittent high-speed wind tunnel of IT CAS CR for 2D cascade measurements equipped by an adjustable supersonic inlet nozzle, perforated inserts at side walls and adjustable perforated tailboard.