The subject for investigation was chosen because of the need for a schlieren system for the axi-symmetrical wind tunnel operated under Naval Ordnance Contract 16498, Task UTX-2-A, at the Defense Research Laboratory, The University of Texas. The system is required to have good sensitivity and relatively high magnification, yet remain compact and simple as possible. By the use of lenses the system is of the single pass type which gives a fairly high light intensity for photography even after the light has been monochromatized. A single pass system requires only a single path optic bench which can be readily adapted and easily adjusted to any wind tunnel installation. In contacting various wind tunnel installations throughout the United States, it was discovered that most of them used the conventional parabolic-mirror type schlieren system which is usually quite large and expensive. This lens type system is designed to be used with a wind tunnel with a small field of view, that is, a tunnel having a test section of small height and length. The system is by no means the best type but is usable and of fairly good quality.
Prepared in cooperation with Johns Hopkins Univ., Silver Spring, Md., Applied Physics Lab. CF-2546.