Influence of Endwall Contouring and Leakage Interaction on the efficiency of turbines with Shrouded Blades



Increasing the process parameters of steam turbines results in high maximum pressures, which leads to very small volume flows in the first stages and consequently requires small blade heights and small height / chord length ratios. The aerodynamic design of these blades still has considerable development potential in order to compensate for the higher specific losses to be expected as a result of the greater proportion of near-wall flow as well as the more serious effect of secondary gap flow phenomena. To limit the gap mass flows, shrouded blades are used in the first stages in highest-pressure and high-pressure steam turbines. A promising measurement for the optimization of these turbines lies in the sidewall contours of such shrouded blades, which have a considerable potential for reducing flow losses in the vicinity of the wall.



Within the scope of this project, flow investigations are carried out in the cavities of shrouded blades and their inlet and outlet planes, as well as in the interaction area of ​​the leakage and main flow. The aim of these investigations is the characterization of secondary flow and mixing losses. At the same time, data is provided for the validation of the parallel numerical simulations. In addition, this project investigates the mixing of hot gasses in the labyrinth seals.



The project is realized as part of the AG Turbo joint project "COORETEC-turbo" and funded by the Federal Ministry for Economic Affairs and Energy (BMWi) in a period of 3.5 years.



Dieter Bohn, Stephan Schwab, Michael Sell
Analysis and Evaluation of the Impact of different Blade Loadings on a 2-Stage Turbine with Shrouded Blades , ASME Paper GT2011-46209

Stephan Schwab, Dominik Wendland, Manfred Wirsum und Michael Sell
Einflüsse von Seitenwandkonturierungen und Leckageinteraktion auf den Wirkungsgrad von Turbinen mit Deckbandbeschaufelungen , 13. Statusseminar AG-Turbo 03.12 bis 04.12.2012

Stephan Schwab, Dominik Wendland, Manfred Wirsum, Michael Sell
Numerical and Experimental Investigation of Flow in a Steam Turbine with Novel Endwall Contoured Blades
Proceedings of 11th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows, May 6-11, 2013, Shenzhen, China

Stephan Schwab, Dominik Wendland, Manfred Wirsum
Numerical and Experimental Investigation of Tangential Endwall Contoured Blades in a 2-Stage Turbine, ASME Paper GT2013-94169