Effective dipole moment for the mode coupling instability: Mapping of self-consistent wake models

2012 ◽  
Vol 19 (7) ◽  
pp. 073708 ◽  
Author(s):  
T. B. Röcker ◽  
S. K. Zhdanov ◽  
A. V. Ivlev ◽  
M. Lampe ◽  
G. Joyce ◽  
...  
2013 ◽  
Vol 135 (6) ◽  
Author(s):  
Yasuhiro Seo ◽  
Hiroshi Yabuno ◽  
Go Kono

To analyze the excitation mechanism of self-excited oscillation in a beam that is in contact with a moving floor surface such as a cleaning blade, which is a beam mounted in a laser printer to clean the photoreceptor, we study a beam subjected to Coulomb friction and theoretically predict the occurrence of self-excited oscillation through mode-coupling instability. We present an extensible beam model, and derive its governing nonlinear equations by means of special Cosserat theory, which allows for the extensibility of the beam to be considered. The boundary conditions on the end of the beam are unique because the end of the beam makes contact with the moving floor surface. We used a discretized linearized governing equation and performed linear stability analysis. The results indicate that self-excited oscillation in the beam is produced due to both Coulomb friction and mode coupling of the bending and extension of the beam based on the extensibility in the axial direction.


2000 ◽  
Vol 61 (2) ◽  
pp. 2086-2088 ◽  
Author(s):  
Amit Kr. Chattopadhyay ◽  
Abhik Basu ◽  
Jayanta K. Bhattacharjee

2008 ◽  
Vol 22 (20) ◽  
pp. 3421-3431
Author(s):  
MALAY K. NANDY

We evaluate the universal turbulent Prandtl numbers in the energy and enstrophy régimes of the Kraichnan-Batchelor spectra of two-dimensional turbulence using a self-consistent mode-coupling formulation coming from a renormalized perturbation expansion coupled with dynamic scaling ideas. The turbulent Prandtl number is found to be exactly unity in the (logarithmic) enstrophy régime, where the theory is infrared marginal. In the energy régime, the theory being finite, we extract singularities coming from both ultraviolet and infrared ends by means of Laurent expansions about these poles. This yields the turbulent Prandtl number σ ≈ 0.9 in the energy régime.


Sign in / Sign up

Export Citation Format

Share Document