Radiative gas-dynamic model of a continuous optical discharge in a gravitational field: quasi-optical approximation

Download

index.pdf

Date

2009-08-07

Author

Rafatov, İsmail

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

212
views

0
downloads

We consider a continuous optical discharge (COD) sustained by a vertically directed weakly focused CO(2) laser beam, in a gravitational field. We used a full two-dimensional radiative gas-dynamic numerical model for the COD, which uses realistic quasi optics and takes refraction of the laser radiation in the plasma properly into account in the description of the laser beam propagation. The model is applied to calculate the parameters of the COD in a converging CO(2) laser beam in free air atmosphere as a function of the laser power. We also demonstrate the effect of the selection of spectral groups, used in the multi-group diffusion approximation of the thermal radiation transport, on the model solutions.

Subject Keywords

Acoustics and Ultrasonics, Electronic, Optical and Magnetic Materials, Surfaces, Coatings and Films, Condensed Matter Physics

URI

https://hdl.handle.net/11511/42013

Journal

JOURNAL OF PHYSICS D-APPLIED PHYSICS

DOI

https://doi.org/10.1088/0022-3727/42/15/155207

Collections

Department of Physics, Article

Suggestions

OpenMETU
Core

Modelling of a continuous optical discharge stabilized by a gas flow in quasi-optical approximation Rafatov, İsmail; Yedierler, Burak (IOP Publishing, 2009-03-07) We consider a continuous optical discharge (COD) sustained by a weakly focused CO(2) laser beam and stabilized by a cold gas flow incident in the direction of the laser radiation propagation. We develop and examine a two-dimensional radiative gas-dynamic model for COD which uses realistic quasi-optics and takes refraction of the laser radiation in the plasma properly into account in describing the laser beam propagation. The model is applied to calculate the parameters of COD in the air flow as functions of...
Perturbation analysis of sheath evolution, with application to plasma source ion implantation Bektursunova, RM; Demokan, O (IOP Publishing, 2001-02-07) A perturbation model has been developed to describe the evolution of an expanding plasma sheath around a cathode after a high-voltage negative pulse is applied to the cathode, simulating the conditions in devices such as those used for plasma source ion implantation. The set of governing equations consists of two coupled collisionless fluid equations for ions, and Poisson's equation and Boltzmann's assumption for electrons. The time-dependent, self-consistent expressions for the potential, ion density and i...
Excitonic effects on the nonlinear optical properties of small quantum dots KARABULUT, İBRAHİM; Safak, H.; Tomak, Mehmet (IOP Publishing, 2008-08-07) The excitonic effects on the nonlinear optical properties of small quantum dots with a semiparabolic confining potential are studied under the density matrix formalism. First, within the framework of the strong confinement approximation, we present the excitonic states and then calculate the excitonic effects on the nonlinear optical properties, such as second harmonic generation, third harmonic generation, nonlinear absorption coefficient and refractive index changes. We find the explicit analytical expres...
Spatial stabilization of Townsend and glow discharges with a semiconducting cathode Salamov, BG; Ellialtioglu, S; Akınoğlu, Bülent Gültekin; Lebedeva, NN; Patriskii, LG (IOP Publishing, 1996-03-14) The physical processes determining the functions of an ionization system and especially the discharge stabilization by the distributed resistance of a semiconducting cathode in such a system are studied. The current-voltage (I-U) characteristics of the system with a semiconducting GaAs cathode are obtained experimentally as functions of the gap pressure P (16-760 Torr) and inter-electrode distance d (10 mu m to 5 mm), which are varied for the first time over very wide ranges. The experiments showed that the...
Tunable near-field radiative transfer by III-V group compound semiconductors Elcioglu, Elif Begum; Didari, Azadeh; Okutucu Özyurt, Hanife Tuba; MENGÜÇ, MUSTAFA PINAR (IOP Publishing, 2019-03-06) Near-field radiative transfer (NFRT) refers to the energy transfer mechanism which takes place between media separated by distances comparable to or much smaller than the dominant wavelength of emission. NFRT is due to the contribution of evanescent waves and coherent nature of the energy transfer within nano-gaps, and can exceed Planck's blackbody limit. As researchers further investigate this phenomenon and start fabrication of custom-made platforms, advances in utilization of NFRT in energy harvesting ap...

Citation Formats

İ. Rafatov, “Radiative gas-dynamic model of a continuous optical discharge in a gravitational field: quasi-optical approximation,” JOURNAL OF PHYSICS D-APPLIED PHYSICS, pp. 0–0, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42013.