Numerical Analysis of Behavior on Opposing Unsteady Supersonic Jets in a Flow Field with Shields

Abstract:

Collision dynamics of opposing unsteady supersonic jets injected in background gas with shock waves were calculated to simulate double pulsed laser ablation. Since the jets are deflected by collision and the motion of debris is ballistic. This characteristic can be used to reduce the number of debris when shields are mounted in front of substrate. The flow of jets through installed shields is complicated by the interaction between shields and jets, and between shields and shock waves. We investigate influence of shield position on the shock waves and the jets by numerical calculations. Axisymmetric two-dimensional compressible Euler equations were solved using the finite volume method by using ANSYS Fluent 14.0.0 code. The shields with slit was mounted parallel to the direction of initially injected jets. In order to investigate the influence of shield position on the shock waves and the jets, the shield position and background gas pressure were adopted as parameters. The jets and shock wave are deflected by collision and they can pass through the slit of shields. The passed shock wave reflects at the substrate mounted behind the slits and it forces back the jet to decrease the jet velocity. The shield position governs the velocity and amount of the jet that reach the substrate.

• Periodical: Materials Science Forum (Volume 910)
• Pages: 96-101
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.910.96
• Online since: January 2018
• Authors: Toshiki Kinoshita, Hiroshi Fukuoka*, Ikurou Umezu
• Keywords: Computational Fluid Dynamics (CFD), Laser Ablation, Shock Wave, Supersonic Jet

References

[1] J. C. Miller et al., Laser ablation, Springer Series in Material Science 28, Springer-Verlag, (1994).

[2] M. N. Ashfold et al., Pulsed laser ablation and deposition of thin films, Chemical Society Reviews, 33. 1, (2004), 23-31.

[3] D. B. Chrisey et al., Pulsed Laser Deposition of Thin Films, John Wiley & Son, (1994).

[4] V. Y. Bratus et al., ESR studies of nanocrystalline silicon films obtained by pulsed laser ablation of silicon targets, Semiconductors, 38. 5, (2004), 598-602.

DOI: 10.1134/1.1755899

[5] I. Umezu et al., Formation of core-shell structured silicon nanoparticles during pulsed laser ablation, Journal of Applied Physics, 107, (2010), 094318.

DOI: 10.1063/1.3374660

[6] K. Kinoshita et al., Improved Surface Smoothness of YBa2Cu3Oy Films and Related Multilayers by ArF Excimer Laser Deposition with Shadow Mask Eclipse Method, Japanese journal of applied physics, 33, (1994), L417.

DOI: 10.1143/jjap.33.l417

[7] A. Marcu et al., Pulsed laser deposition of YBCO thin films in a shadow mask configuration, Thin Solid Films, 360, (2000), 166-172.

DOI: 10.1016/s0040-6090(99)01083-4

[8] I. Umezu et al., Effects of collision between two plumes on plume expansion dynamics during pulsed laser ablation in background gas, Applied Physics A, 110, (2012), 629-632.

DOI: 10.1007/s00339-012-7141-x

[9] I. Umezu et al., Emission induced by collision of two plumes during pulsed laser ablation, Applied Physics A, 101, (2010), 133-136.

DOI: 10.1007/s00339-010-5772-3