Schlieren and Shadowgraph Imaging in the Great Outdoors
نویسنده
چکیده
A review is given of outdoor schlieren and shadowgraph imaging, beginning with an historical perspective. The optical principles of the sunlight shadowgraph method and schlieren observation by background distortion are discussed. Examples and illustrations are given of the visualization of outdoor thermal convection, combustion, and explosion phenomena. Jet aircraft and high-speed flight are featured as important subjects for such flow visualization. Finally, though most of these examples are visible to the unaided eye, some instruments are available for enhanced outdoor refractive imaging in special cases.
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