Improved Fidelity Predictions for Resonant Stress in Turbine Components

ABSTRACT: The objective of this SBIR is to deliver an improved physics-based design system for turbine component durability by providing a means to predict aerodynamic forcing and aerodynamic damping in relevant geometries via a single high fidelity calculation. A nine-month, four-phase work plan is proposed to develop the capability for the solver Code Leo and demonstrate its use in turbine component design. Specifically, a non-linear harmonic balance analysis method coupled with an advanced transpiration boundary condition is proposed for aerodynamic damping prediction, which we believe will enable designers to gain both accuracy and speed. This capability will be validated against an existing turbine geometry and then used to modify that geometry for resonant stress reduction. During Phase I, attention will also be given to the formulation of a structural solver for Code Leo to enable fully coupled fluid/structure computations as part of Phase II. Discussions with gas turbine manufacturers indicate strong support for this type of capability for high cycle fatigue and flutter prediction. Williams International is especially interested and has provided AeroDynamic Solutions a Letter of Support for this proposal. BENEFIT: The proposed system will improve the ability for commercial and military engine manufacturers to anticipate and mitigate resonant stress-related issues during design, resulting in lower incidence of fatigue failure and improved aircraft life cycle costs. For aircraft and hovercraft engines (Air Force, NASA), the system could be used to address durability challenges common in fan and low pressure turbine designs. The system is may also be applied equally as effectivly to other sectors of the turbomachinery market, such as industrial gas turbines (HCF), automotive turbochargers (HCF) and wind turbines (flutter).