Development of fluid-curtain sealing technology for improving the efficiency and operational flexibility of large power generation turbines.

Much of the recent R&D activity to develop new turbomachinery sealing technologies for improved efficiency and increased operational flexibility of steam and gas turbines has focused on the development of new types of contacting aerodynamic sealing devices, such as brush seals and leaf seals. Fluidic or fluid curtain seals have been recognized in patents dating back to 1950's, although none of the major manufacturers has yet tried to deploy the technology in their turbine designs. Fluidic sealing for turbines has recently started to receive some research attention and it is becoming apparent that it has the potential to offer significant performance advances over conventional sealing technologies. Fluidic seals use aerodynamic flow features (jets or curtains of fluid) to create blockage/loss and reduce leakage. They are therefore potentially much more robust than many other types of advanced new turbine seal. This project will build on some initial proof of concept testing that has already been successfully completed by Durham University. The work will involve a combination of numerical and analytical modelling work and experimental testing. The PhD study will aim to develop and evaluate fluidic seal technology for some target applications in ALSTOM turbine products.