Computational fluid dynamics and virtual aeroengine modelling

Abstract

Use of large scale computational fluid dynamics (CFD) models in aeroengine design has grown rapidly in recent years as parallel computing hardware has become available. This has reached the point where research aimed at the development of CFD-based "virtual engine test cells" is underway, with considerable debate of the subject within the industrial and research communities. The present paper considers and illustrates the state-of-the art and prospects for advances in this field. Limitations to CFD model accuracy, the need for aero-thermo-mechanical analysis through an engine flight cycle, coupling of numerical solutions for solid and fluid domains, and timescales for capability development are considered. While the fidelity of large scale CFD models will remain limited by turbulence modelling and other issues for the foreseeable future, it is clear that use of multi-scale, multi-physics modelling in engine design will expand considerably. Development of user-friendly, versatile, efficient programs and systems for use in a massively parallel computing environment is considered a key issue.

Coupled FE–CFD thermal analysis for a cooled turbine disk

“…This demonstrates the potential for practical application of this method, and is a step towards virtual engine modelling as discussed by Chew and Hills. 2 Accuracy of the CFD-based model was comparable to that of an industrial standard baseline FE model that had been adjusted to match engine data. Significant differences between the baseline and coupled models were found in regions where there are no thermocouple data.…”

“…With advances in parallel computation and numerical modelling, there is a trend in turbomachinery design systems towards the “virtual” or “whole” engine simulation. 2,3 Recognising the importance of aero-thermo-mechanical effects, coupling of FE component models with detailed CFD models is receiving considerable attention from the turbomachinery research community. Several researchers have demonstrated FE–CFD coupled analysis capability for heat transfer calculations in gas turbines.…”

Evaluation and application of advanced CFD models for rotating disc flows

“…Thus, sealing the internal air system has a significant impact on engine efficiency and other aspects of performance. As has been reported elsewhere, for example in references, 1,2 the importance of internal air systems has stimulated considerable research with computational fluid dynamics (CFD) playing an increasingly significant role. CFD capability has now reached the point where high fidelity methods such as direct numerical simulation (DNS) and large-eddy simulation (LES) are used in research, but their application is severely limited by computational requirements.…”

Coupled Fluid-Structure Transient Thermal Analysis of a Gas Turbine Internal Air System With Multiple Cavities

“…A general trend in computational modeling of modern turbo-machinery systems is to move towards the "virtual" or "whole" engine simulation [2]. As far as modeling of the internal air systems is concerned, a natural and incremental advance in both the complexity and the accuracy of current modeling is to include and interconnect multiple CFD domains within a single simulation.…”

“…The user-specified boundary conditions rely heavily on correlations, they require a significant effort from an end-user to correctly represent the complex physical phenomena over a wide range of operating conditions. As the geometries of modern air systems grow in complexity, current models with correlations become painful to build and increasingly obsolete.A general trend in computational modeling of modern turbo-machinery systems is to move towards the "virtual" or "whole" engine simulation [2]. As far as modeling of the internal air systems is concerned, a natural and incremental advance in both the complexity and the accuracy of current modeling is to include and interconnect multiple CFD domains within a single simulation.…”