Interferometric measurements in a turbine cascade using image-plane holography
Abstract
A holographic technique used to produce image plane interferograms with white light reconstruction is described. This was used to study the transonic flow in a passage of a turbine stator cascade at a typical Reynolds number, Mach number, and free stream to blade surface temperature ratio. Both absolute holographic interferograms (fringes of constant flow density) and differential holographic interferograms (changes of density in 100 microsecs) are presented showing fine details in the boundary layer flow, trailing edge shocks, and wake structure. By counting the fringes on the interferograms, the free stream and surface Mach numbers and boundary layer temperature gradients can be determined.
- Publication:
-
Gas Turbine Conference and Products Show
- Pub Date:
- March 1980
- Bibcode:
- 1980gatu.confU....B
- Keywords:
-
- Cascade Flow;
- Engine Monitoring Instruments;
- Flow Visualization;
- Gas Turbine Engines;
- Holographic Interferometry;
- Image Reconstruction;
- Turbine Blades;
- Boundary Layer Flow;
- Engine Tests;
- Flow Measurement;
- Free Flow;
- Mach Number;
- Reynolds Number;
- Temperature Gradients;
- Instrumentation and Photography