Visualization of the Flow at the Tip of a High Speed Axial Flow Turbine Rotor Blade - An Assessment of Flow Visualisation Techniques and the Requirement of the Experimental Turbine.
Abstract
The field of flow visualisation has been reviewed and its application to the study of the flow near the tip of an unshrouded axial turbine rotor discussed in detail. The logical conceptualisation of experiments which could lead to a final understanding of the flow structure was developed and how this leads to test turbine design philosophy is suggested. The rotor periodicity shed by the stator requires that particle of pulse tracing is needed rather than the more universal continuous streamline trace which arises from a continuous tracer injection at a point in a flow. While the whole field of flow visualisation at a rotor tip is demanding because of its very nature, pulse tracking will place a greater demand on the development of new skills and techniques. Since streamline tracking is somewhat more standard, these demands will not be as great. A fundamental choice does however need to be made between the two methods. The suggested experimental turbine should thus, always with the facility of infinitely variable Mach number, model the following: (1) stationary annular cascade with tip clearance inside a stationary outer endwall; (2) Stationary annular cascade with tip clearance inside a moving endwall; (3) The transfer of flow visualisation techniques developed into the rotating frame; (4) Fully rotating rotor with no inlet periodicity; (5) Fully rotating rotor with inlet periodicity.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1987
- Accession Number
- ADA189929
Entities
People
- D. Adler
- J. P. Bindon
Organizations
- Technion – Israel Institute of Technology