SIMPLE METHODS AND INSTRUMENTATION FOR VERY SHORT EXPOSURE, HIGH REPETITION RATE KINEMATOGRAPHY IN CONJUNCTION WITH FLUID ATOMIZATION STUDIES

摘要

The high voltage discharge of a pulsed light source with coaxial capacitor and extremely low inductance (Fischer-Nanolite) has been employed successfully for ultra-short-time exposure of rapidly changing phenomena in the boundary layer of two-phase-flow. By charging the coaxial capacitor from a much greater capacitor through a preset variable high comic resistor, light pulse series could be produced at a shot repetition rate up to 8 kops. Due to the extremely short exposure time in the nanosecond range pictures could be taken without motion tour on the quickly moving film, fixed on a rotating drum. Thus no rotating prism was necessary. Irregularities of the frame spacing, resulting from the time jitter of the discharge caused by its complex nature, do not seriously influence the evaluation of the projected pictures, but prevent motion pictures, which are highly desired, from being taken.