Conference paper ASME GT2011-45624, Vancouver, Canada
G. Kröger, C. Voß, E. Nicke, C. Cornelius
Year of publication: 2011
In this paper the theory and application of axisymmetric endwall contouring for high pressure compressor stages of gas turbines are presented. The application is carried out at an existing high pressure blading from Siemens Energy.
The theory section covers the influence of endwall contouring on tip clearance flows and the flowfield in the blade tip region. A simplified 2D fluid simulation is applied to explain the effects nearby a waved endwall.
In the application section a coupled optimization of endwall contouring and blade tip is presented. Therefore, an optimized blade tip profile is matched with a likewise optimized endwall contouring. As a result the isentropic stage efficiency was increased by ca. 0.8% und blockage near the endwall was considerably reduced.
Finally the optimization results are applied on the rear stage of a comprehensive model of a Siemens gas turbine. The overall efficiency of the compressor was significantly increased.