Propagation of 632.8 nm and 4.67 µm laser beams in a turbulent flow containing CO(2) and H(2)O at high temperatures

William M Isterling; Bassam B. Dally; Zeyad T. Alwahabi; Miro Dubovinsky; Daniel Wright

doi:10.1117/12.803577

2 October 2008 Propagation of 632.8 nm and 4.67 µm laser beams in a turbulent flow containing CO₂ and H₂O at high temperatures

William M Isterling, Bassam B. Dally, Zeyad T. Alwahabi, Miro Dubovinsky, Daniel Wright

Author Affiliations +

Proceedings Volume 7115, Technologies for Optical Countermeasures V; 71150H (2008) https://doi.org/10.1117/12.803577
Event: SPIE Security + Defence, 2008, Cardiff, Wales, United Kingdom

Abstract

Laser based missile defence systems (DIRCM) are being increasingly employed on aircraft. In certain circumstances the laser must pass through the exhaust gases of the aircraft engine. In order to predict the degree of divergence and dispersion of the laser, an understanding of the exhaust gas structure and its influence is required. Specifically the effect of parameters such as temperature, carbon dioxide, turbulence intensity and length scales as well as the laser beam wavelength and beam diameter. A parametric study under laboratory controlled conditions was undertaken to examine these effects. The results of beam propagation through high temperature turbulent flows and for various CO₂ and H₂O concentrations are presented in this paper for wavelengths 632.8 nm and 4.67 μm. It was found that the beam displacement showed an approximate inverse square relationship to temperature. At high combustion temperatures the 632.8 nm beam was significantly broken-up and dispersed. Displacement of both beams appeared to be asymptotic above 600°C. Carbon dioxide absorption effects were found not to significantly influence the beam displacement at the wavelengths and temperatures studied. Quantifying these effects at high temperatures will assist with the development of a parametrically based laser beam propagation model.

Citation Download Citation

William M Isterling, Bassam B. Dally, Zeyad T. Alwahabi, Miro Dubovinsky, and Daniel Wright "Propagation of 632.8 nm and 4.67 µm laser beams in a turbulent flow containing CO₂ and H₂O at high temperatures", Proc. SPIE 7115, Technologies for Optical Countermeasures V, 71150H (2 October 2008); https://doi.org/10.1117/12.803577

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available