John J. Marra

Advanced Hydrogen Turbine Development Update

Siemens Energy, Inc. was awarded a contract by the U.S. Department of Energy for the first two phases of the Advanced Hydrogen Turbine Development Program. The 3-Phase, multi-year program goals are to develop an advanced syngas, hydrogen and natural gas fired gas turbine fully integrated into coal-based Integrated Gasification Combined Cycle (IGCC) plants.The program goals include demonstrating:• A 3–5% point improvement in combined cycle efficiency above the baseline,• 20–30% reduction in combined cycle capital cost• Emissions of 2 ppm NOx @ 15% O2 by 2015.Siemens is currently well into Phase 2 of the program and has made significant progress in several areas. This includes the ability to attain the 2015 Turbine Program performance goals by developing component and systems level technologies, developing and implementing validation test plans for these systems and components, performing validation testing of component technologies, and performance demonstration through system studies.Siemens and the Advanced Hydrogen Turbine Program received additional funds from the American Recovery and Reinvestment Act (ARRA) in 2010. The additional funding serves to supplement budget shortfalls in the originally planned spend rate.The development effort has focused on engine cycles, combustion technology development and testing, turbine aerodynamics/cooling, modular component technology, materials/coatings technologies and engine system integration/flexibility considerations. High pressure combustion testing continues with syngas and hydrogen fuels on a modified premixed combustor. Advanced turbine airfoil concept testing continues. Novel manufacturing techniques were developed that allow for advanced castings and faster time to market capabilities. Materials testing continues and significant improvements were made in lifing for Thermal Barrier Coatings (TBC’s) at increased temperatures over the baseline. Studies were conducted on gas turbine/IGCC plant integration, fuel dilution effects, varying air integration, plant performance and plant emissions. The results of these studies and developments provide a firm platform for completing the advanced Hydrogen Turbine technologies development in Phase 2.Copyright

Multi-Disciplinary Optimization of Mid-Span Shroud Ring Structure: A Multi-Parameter Geometry Study Case

In modern industrial high-output, high-efficiency engines, long turbine blades can require the use of a mid-span or partial-span damping ring for damping vibrations. However, the inclusion of a mid-span damping shroud, or “snubber,” can have negative effects on the aerodynamic performance of the gas turbine stage and engine. Therefore, a method of coupling two independent computational fluid dynamics and finite element structure software tools under an optimization environment was applied to minimize the drag force caused by the snubber, while maximizing the structural life of the blade.Following the earlier two-parameter (the shroud width and taper ratio) shroud geometry study by the authors, this study extends to the five-parameter geometry model to approach a higher performance design with controllable computational time as well. For the optimized turbine blade shroud in this case, 14.5% reduction of the maximum material stress and 22.6% decrease in the drag force from original snubber design has been accomplished.Copyright

Design Optimization of Turbo-Machinery Components With Independent FEA and CFD Tools in an Optimization Software Environment: A Mid-Span Shroud Ring Study Case

Shrouds are important for damping vibrations in gas turbine blades. In modern industrial high-output, high-efficiency engines, long turbine blades can require the use of a mid-span or partial-span damping ring. However, the inclusion of a mid-span damping shroud, or “snubber,” can have negative effects on the aerodynamic performance of the gas turbine stage and engine. Therefore, a method of iterative study and optimization was applied to minimize the drag force caused by the snubber, while maximizing the structural life of the blade. The approach used integrated design environment software to perform parametric studies of the design space in preparation for optimization of the blade snubber geometry. The drivers employed in Isight 4.0/4.5 [9] optimization software carried out the parametric study and reported the results to the designer. Considering these results, the designer chose the initial seeding geometry of the optimization driver which greatly reduced analysis time and the time required to reach the design objectives. This approach provides an integrated design workflow and facilitates parametric studies of advanced gas turbine blade component geometry, and the optimization of the component to meet targets of minimized aerodynamic drag force and maximized low-cycle fatigue life, goals crucial to the development of an advanced and efficient power generation gas turbine.Copyright