The compressor is a particularly sensitive component in a gas turbine engine. Variations from design geometry or operating conditions can have detrimental effects on performance, efficiency and compressor life. In this work the propagation of secondary air system operational uncertainty sources on a rotor-stator cavity at the front of a large turbofan IPC are assessed. The calculations are carried through from appropriate Computational Fluid Dynamics (CFD) analyses, characterising the flow and heat transfer in the cavity adjacent to an IP1 disc, to the FE Thermo-mechanical calculations. The application provides an example demonstration how uncertainty quantification may be undertaken for compressor analysis involving intensive CFD computations. The non-deterministic solution provides probabilistic definitions for disc temperatures and blade tip clearances, as key parameters in the design of the component. Whilst CFD has found increasing use in gas turbine air system R&D and design applications, resource requirement has almost always limited its use to deterministic single-input single-output cases. Here, by employing efficient uncertainty quantification based on Polynomial Chaos Methodologies to CFD, the air mass flow and temperature feed to the cavity are treated as operational uncertainty sources. Both single variable and multi-variable sources are considered. The CFD-FE link is established through a Temperature Influence Coefficient methodology and in propagating and managing the uncertainties through both analyses, means and standard deviations in the key design parameters are derived. The value of such a methodology in contrast to deterministic calculations is discussed from the view point of the designer with reference to component temperatures and thermal growths.

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