The numerical assessment of T-tail flutter requires a nonlinear description the structural deformations when unsteady aerodynamic forces comprise terms from lifting surface roll motion. For linear flutter, deformation vertical tail plane (VTP) out-of-plane bending results in spurious stiffening proportional to steady lift forces, which is corrected by incorporating second-order equations While ...

This paper initiates a mathematical theory of aeroelasticity centered on the canonical problem of the flutter boundary an instability endemic to aircraft that limits attainable speed in the subsonic regime. We develop a continuum mathematical model that exhibits the known flutter phenomena and yet is amenable to analysis non-numeric theory. Thus we model the wing as a cantilever beam and limit ...

Studies were performed using bipolar atrial wire electrodes to record atrial electrograms and to pace the atria in 27 patients who developed atrial flutter after open heart surgery. Two types of atrial flutter, classic or type I atrial flutter, and type II atrial flutter, were identified. Both types of atrial flutter were characterized by uniformity of the beat-to-beat atrial cycle length, morp...

OBJECTIVE To develop new electrocardiographic (ECG) criteria for the differentiation between counterclockwise and clockwise atrial flutters. BACKGROUND Traditionally, the ECG differentiation between counterclockwise and clockwise atrial flutters is based on the flutter wave polarity in the inferior leads. However, determination of flutter wave polarity is subjective and sometimes difficult, e...

BACKGROUND Right atrial flutter cycle length can prolong in the presence of antiarrhythmic drug therapy. We hypothesized that the cycle length of right atrial isthmus dependent flutter would correlate with right atrial cross-sectional area measurements. METHODS 60 patients who underwent ablation for electrophysiologically proven isthmus dependent right atrial flutter, who were not on Class I ...

1 Robert O. Lawton Distinguished Professor, Department of Mathematics, Fellow AIAA. 2 Post-Doctoral Research Associate, Department of Mathematics. 3 Research Scientist, Structural Acoustics Branch, Aerodynamics, Aerothermodynamics and Acoustics Competency, Member AIAA. 4 Senior Research Scientist, Computational Modeling and Simulation Branch, Aerodynamics, Aerothermodynamics and Acoustics Compe...

The stability boundaries of a very flexible wing are sought to inform wind-tunnel flutter test campaign. objective is twofold: identify via simulation the relevant physical processes be explored while ensuring safe and nondestructive experiments, provide benchmark case for which computational models data freely available. Analyses have been independently carried out using two geometrically nonl...