Development of Industrial Transonic Turbine Stages

Contract no. BRPR-CT-98-0756
Project no. BE97-4633
Coordinator: Nuovo Pignone (IT)

start: August 1998
duration: 36 months
status: partner





Contractors: Nuovo Pignone (I), TU Graz (AT), University of Florence DEF (I), Eldim (NL), DANTEC (DK), Fornai (I)



Project full title: Advanced Industrial Gas Turbines: Development of Transonic Cooled Stages for High Pressure Ratios through Innovative Design, Manufacturing and Testing Techniques.
For industrial, land based gas turbines with powers ranging from 1 to 40 MW, the market trend is towards higher and higher efficiency machines at constant and possibly decreasing costs per kW shaft power. Higher efficiencies can be achieved with advanced 3D aerodynamic design techniques and with the increase in the maximum cycle temperatures associated with advanced cooling techniques and hot part materials. These latter however imply substantial increases in the manufacturing costs. Therefore, to meet the cost objective, it is necessary to reduce the number of stages. This can be achieved only through the availability of advanced design turbine stages, with very high aerodynamic and thermodynamic loading, and at the same time with efficiencies above conventional technology levels for equal or better reliability and lifetime.
The main aim of the program is to provide significantly higher efficiency than current technology will allow for, while at the same time reducing the manufacturing costs through the use of a lower number of components. To achieve this goal it is required to:

  • limit the number of turbine stages to two for a single-spool machine
  • make the aerodynamic design suitable for pressure ratios in the order of 18:1 to 20:1
  • design the high Mach number, high pressure ratio blading suitable to provide very high aerodynamic expansion efficiency, but within stress and metal temperature constrains suitable to assure reliability and long life.

These requirements imply the use of transonic stages with associated problems of cooling effectiveness of conventional cooling techniques.
Five concurrent development processes can be identified which will both provide an essential contribution to the specific aim of the project:

  • development of design tools for unprecedented advanced turbine stages;
  • development of an innovative film cooling system for blades;
  • development of new manufacturing technologies for cooling ports in blades;
  • development of an unprecedented experimental database on full scale transonic stages;
  • setup of an unprecedented and worldwide unique experimental facility and measuring technique.


  1. Seyr A., Kulhanek G., Neumayer F., Rossi E. and Sanz W., 2001, "Performance Measurement of the Second Stage of a Transonic Turbine" ASME Turbo Expo 2001, New Orleans, LA, 4-7 June, 2001, ASME paper 2001-GT-0490.
  2. Marconcini M., Pacciani R., 2003, "Numerical Investigation of Wake-Shock Interactions and Clocking in a Transonic HP Turbine", ASME Turbo Expo, Atlanta, GA, USA, 16-19 June, 2003, ASME paper 2003-GT-38401. Conf. Proc. Vol. 6: Turbo Expo 2003, Parts A and B, Turbomachinery: Axial Flow Turbine Aerodynamics, pp. 235-243. ISBN 0-7918-3689-4. DOI:10.1115/GT2003-38401
  3. Arnone A., Marconcini M., Pacciani R., Spano E., 2003, "Challenges in Predicting Row Interaction Effects in Axial Turbines", 33rd AIAA Fluid Dynamics Conference and Exhibit, Orlando, Florida, 23-26 June, 2003, AIAA paper 2003-3994 (Invited Paper)