Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: ponderomotive force

Sortuj według:

Ogranicz wyniki do:

Analysis of factors affecting destabilization of a viscous liquid flow in channels

Mamedov Asiman, Hnativ Roman, Yakhno Oleg, Murashchenko Alena

International Journal of Applied Mechanics and Engineering

2023

Vol. 28, no. 3

86--100

An analysis of the influence of inertia forces and ponderomotive forces on the destabilization of the flow of viscous fluids in the hydrodynamic initial section is given. Cases of flow of viscous, anomalously viscous and electrically conductive liquids are considered; the degree of influence of mass forces on the destabilization of the flow is estimated. As applied to the flow in the hydrodynamic initial section, the degree of influence of inertia forces from convective acceleration and forces with a magnetic nature can be different. Inertia forces stimulate the accelerated movement of the fluid, and in the case of forces with a magnetic nature, ponderomotive forces contribute to deceleration, which is confirmed by the results of studies of the velocity field. Recommendations are given for calculating the length of the hydrodynamic initial section in the presence of mass forces with different nature.

Ponderomotive self-focusing of a short laser pulse under a plasma density ramp

Kant N., Saralch S., Singh H.

Nukleonika

2011

Vol. 56, No. 2

149-153

The ponderomotive self-focusing of a short laser pulse in an underdense plasma under a plasma density ramp is analyzed. The pulse may acquire a minimum spot size due to the ponderomotive self-focusing. Beyond the focus, the nonlinear refraction starts weakening, and the spot size of the laser pulse increases, resulting in an oscillatory self-focusing and defocusing behavior of the beam with the propagation distance. In order to minimize the defocusing, we introduce a localized upward plasma density ramp. Due to the upward plasma density ramp, the laser beam retains a minimum spot size. Self-focusing becomes stronger with a mild ripple as the propagation distance increases. The conditions for the ponderomotive self-focusing for suitable parameters of the laser beam and the plasma are determined. The plasma density ramp of the considered type may be observed in gas jet plasma experiments.

Electromagnetic initiation of slip: Laboratory model

Chelidze T., Gvelesiani A., Varamashvili N., Devidze M., Chikhradze V., Tchelidze Z., Elashvili M.

Acta Geophysica Polonica

2004

Vol. 52, nr 1

49-62

In the paper, the results of laboratory experiments on the electromagnetic (EM) initiation of mechanical instability (slip) are presented. Series of strong EM pulses were applied to the mechanical system driven close to the critical state, namely, to the (dry) rock samples placed on an inclined supporting sample at the slope angle less than, but close to the critical slip angle. The elementary theoretical model founded on the analysis of ponderomotive forces in dielectrics and explaining basic experimental data is suggested.