The benchmark active controls technology and wind tunnel test program at NASA Langley Research Center was started with the objective to investigate the nonlinear, unsteady aerodynamics and active flutter suppression of wings in transonic flow. The paper will present the flutter suppression control law design process, numerical nonlinear simulation and wind tunnel test results for the NACA 0012 ...

In this paper, a systematic method to suppress transonic buzz with feedback is presented. A trailing edge control surface in the form of part-span flap was used only modify and unsteady aerodynamic loading on wing. The rotation provide feedback, which consisted weighted linear combination amplitudes principal modes structure, referred as law. linear, optimal law, that synthesized systematically...

We report a novel phenomenon in carbon nanotube based ultra-fast mechanical devices, the trans-phonon effect, which resembles the transonic effects in aerodynamics. It is caused by dissipative resonance of nanotube phonons similar to the radial breathing mode, and subsequent drastic surge of the dragging force on the sliding tube, and multiple phonon barriers are encountered as the intertube sl...

The benchmark active controls technology and wind tunnel test program at NASA Langley Research Center was started with the objective to investigate the nonlinear, unsteady aerodynamics and active flutter suppression of wings in transonic flow. The paper will present the flutter suppression control law design process, numerical nonlinear simulation and wind tunnel test results for the NACA 0012 ...

SUMMARY Brief consideration of current approaches to the prediction of unsteady wing loading in mixed subsonic and supersonic flow shows a wide variety of method and a clear need for economy in transonic aerodynamic calculations for flutter clearance in subsonic flight. In support of measurements of steady and oscillatory pressure distributions on a particular wing, an approximate theoretical t...

This study investigates the aerodynamic and aeroelastic characteristics of a transonic axial compressor, focusing on blade count reduced rotor behavior. The analysis is based experiments, conducted at Transonic Compressor Darmstadt test rig Technical University compulsory simulations. In order to obtain measurement data for detailed investigation, extensive steady unsteady instrumentation was a...

The simulation of the store separation using the automatic coupling of dynamic equations with flow aerodynamics is addressed. The precision and cost (calculation time) were considered as comparators. The method used in the present research decreased the calculation cost while limiting the solution error within a specific and tolerable interval. The methods applied to model the aerodynamic force...