New laser high speed measurement techniques in aerodynamics
Abstract
The technique of differential interferometry as applied to laser photography of flow processes in pure gases is described. Of particular advantage is the method of double exposure using complementary light, by which even weak, rapidly propagating waves can be observed and measured in the presence of strong stationary density variations. Sensitivity of optical path determination is increased two orders of magnitude by employing direct optronic recording of intensity instead of photographic recording. It is often useful to apply a multiple-beam method, which permits fine probing of small areas. Dust particles in the submicron size range carried by the flows can be used as indicators of local velocities.
- Publication:
-
High Speed Photography
- Pub Date:
- 1975
- Bibcode:
- 1975hsp..proc...41S
- Keywords:
-
- Differential Interferometry;
- Flow Measurement;
- High Speed Cameras;
- Laser Applications;
- Optical Measuring Instruments;
- Photographic Measurement;
- Aerodynamics;
- Electronic Control;
- Optical Paths;
- Photographic Recording;
- Lasers and Masers