Computational-fluid-dynamics investigation of aeromechanics

A computational-fluid-dynamics (CFD) tool was developed and applied to a variety of aeromechanics problems, including both forced response and flutter. This three-dimensional nonlinear, viscous, time-accurate code, in conjunction with a large parallel network, is used to demonstrate the mature capability of CFD-based tools for aeromechanical analyses. Examples of multistage blade-row interaction analyses are presented and compared against detailed experimental data highlighting the fidelity of current CFD tools. Flutter analyses of isolated blade rows are also compared to data and used to demonstrate several classical aeromechanical concepts such as influence coefficients, the destabilizing effect of neighboring blades in cascade flutter, the depiction of an aerodynamic damping map, and the flutter benefit of frequency mistuning. These two capabilities, multistage and flutter, are then combined to examine the effect of multistage interaction on the flutter problem. Finally, the reasons for extending the above modeling to include full-aeroelastic capability are discussed, and an example is presented.