Nonlinear Transient Dynamics of Photoexcited Resonant Silicon Nanostructures

ACS Photonics ◽  
2016 ◽  
Vol 3 (9) ◽  
pp. 1546-1551 ◽  
Author(s):  
Denis G. Baranov ◽  
Sergey V. Makarov ◽  
Valentin A. Milichko ◽  
Sergey I. Kudryashov ◽  
Alexander E. Krasnok ◽  
...  
Keyword(s):  
Transient Dynamics ◽  
Silicon Nanostructures ◽  
Nonlinear Transient ◽  
Nonlinear Transient Dynamics

Nonlinear transient dynamics of the driven Klein-Gordon solitons

1995 ◽  
Vol 52 (1) ◽  
pp. 1241-1244 ◽  
Author(s):  
Eva Majerniková ◽  
Y. B. Gaididei ◽  
O. M. Braun
Keyword(s):  
Transient Dynamics ◽  
Klein Gordon ◽  
Nonlinear Transient ◽  
Nonlinear Transient Dynamics

Tilt-Wing Rotorcraft Dynamic Analysis Using Multibody Formulation

1992 ◽  
Author(s):  
Patrick J. O’Heron ◽  
Parviz E. Nikravesh ◽  
Ara Arabyan ◽  
Donald L. Kunz
Keyword(s):  
Flight Control ◽  
High Speed ◽  
Equations Of Motion ◽  
Flight Path ◽  
Minimal Set ◽  
Near Wake ◽  
Highly Nonlinear ◽  
Nonlinear Transient ◽  
Nonlinear Transient Dynamics ◽  
Rotor Assembly

Abstract A model is presented that can be used to simulate the highly nonlinear transient dynamics associated with advanced rotorcraft conversion processes. Multibody equations of motion of the fuselage, the tilting wing, and the rotor assembly are derived using a minimal set of coordinates. An enhanced aerodynamics model is employed to account for unsteadiness and nonlinearity in the near-wake aerodynamics, with a dynamic uniform inflow to compute the far-wake aerodynamics, and a flight control system is employed to compute the blade pitch settings that are necessary to achieve a desired flight path. The model is subjected to a demanding flight path simulation to illustrate that it can perform vertical take-off, hover, tilt-wing conversion, and high-speed forward flight maneuvers effectively.

scholarly journals Recursive dynamic mode decomposition of transient and post-transient wake flows

2016 ◽  
Vol 809 ◽  
pp. 843-872 ◽  
Author(s):  
Bernd R. Noack ◽  
Witold Stankiewicz ◽  
Marek Morzyński ◽  
Peter J. Schmid
Keyword(s):  
Dynamic Mode Decomposition ◽  
Attractive Alternative ◽  
Dynamic Mode ◽  
Cylinder Wake ◽  
Frequency Content ◽  
Mode Decomposition ◽  
Nonlinear Transient ◽  
Galerkin Models ◽  
Nonlinear Transient Dynamics ◽  
Proper Orthogonal

A novel data-driven modal decomposition of fluid flow is proposed, comprising key features of proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD). The first mode is the normalized real or imaginary part of the DMD mode that minimizes the time-averaged residual. The $N$th mode is defined recursively in an analogous manner based on the residual of an expansion using the first $N-1$ modes. The resulting recursive DMD (RDMD) modes are orthogonal by construction, retain pure frequency content and aim at low residual. Recursive DMD is applied to transient cylinder wake data and is benchmarked against POD and optimized DMD (Chen et al., J. Nonlinear Sci., vol. 22, 2012, pp. 887–915) for the same snapshot sequence. Unlike POD modes, RDMD structures are shown to have purer frequency content while retaining a residual of comparable order to POD. In contrast to DMD, with exponentially growing or decaying oscillatory amplitudes, RDMD clearly identifies initial, maximum and final fluctuation levels. Intriguingly, RDMD outperforms both POD and DMD in the limit-cycle resolution from the same snapshots. Robustness of these observations is demonstrated for other parameters of the cylinder wake and for a more complex wake behind three rotating cylinders. Recursive DMD is proposed as an attractive alternative to POD and DMD for empirical Galerkin models, in particular for nonlinear transient dynamics.

Sign in / Sign up

Export Citation Format

Share Document