A two-spark Schlieren system for very-high velocity measurement

Abstract

To produce movies of supersonic flows, from which meaningful information can be extracted, is a non-trivial task. In a supersonic wind tunnel, speeds are of the order of 1,000 m/s and the scale of turbulent structures is typically of the order of millimeter. To capture the flow details, exposure times of less than 0.1 µs, and framing rates from 1 to 100 µs are desirable. While high-speed movie cameras with framing rates up to 5 million per second are commercially available, they are expensive, require an extremely-powerful light source, and are inflexible as to adjusting the exposure and the framing rate independently.

Additional details