Abstract
Laser-induced thermal acoustics (LITA) was used with heterodyne detection to measure simultaneously and in a single laser pulse the sound speed and flow velocity of -seeded air in a low-speed wind tunnel up to Mach number . The uncertainties of the velocity and the sound speed measurements were and 0.5%, respectively. Measurements were obtained through a nonlinear least-squares fit to a general, analytic closed-form solution for heterodyne-detected LITA signals from thermal gratings. Agreement between theory and experiment is exceptionally good.
© 2000 Optical Society of America
Full Article | PDF ArticleMore Like This
Roger C. Hart, G. C. Herring, and R. Jeffrey Balla
Opt. Lett. 27(9) 710-712 (2002)
Roger C. Hart, R. Jeffrey Balla, and G. C. Herring
Appl. Opt. 40(6) 965-968 (2001)
Stefan Schlamp, Eric B. Cummings, and Hans G. Hornung
Appl. Opt. 38(27) 5724-5733 (1999)