Pulsed Laser Diode for Use as a Light Source for Short-Exposure, High-Frame-Rate Flow Visualization
A pulsed laser diode (PLD) is demonstrated as a practical light source for high-speed digital schlieren and shearing-interferometric cinematogrpahy. Frame rates of greater than 300k fps with exposure times on the order of 10 ns have been achieved with an inexpensive and user-friendly setup. The light source has primarily been used in our laboratory to study nonsteady phenomena in high-speed gas flows. Examples are presented to illustrate the usefulness of the PLD as a light source with characteristics of a narrow band of wavelength, short exposure time, high frame-rate, and long pulse train duration.
© 2015 American Institute of Aeronautics and Astronautics. The authors would like to thank Bahram Valiferdowsi for help running T5. This work was an activity that was part of National Center for Hypersonic Laminar-Turbulent Research, sponsored by the Integrated Theoretical, Computational, and Experimental Studies for Transition Estimation and Control project, supported by the U.S. Air Force Office of Scientific Research and the National Aeronautics and Space Administration (FA9552-09-1-0341). Additionally, this work was supported in part of the Transition Delay in Hypervelocity Boundary Layers by Means of CO2/Acoustic Interactions project, sponsored by the Air Force Office of Scientific Research (FA9550-10-1-0491). J. Damazo was supported by an NDSEG Fellowship.