ABOUT THE INFLUENCE OF THE CLEARANCE BETWEEN THE WORKING BLADES AND HOUSING OF A RADIAL TURBINE ON ITS EXPONENT
Abstract
The results of a 1959 experimental study of dissipation in an air radial turbine are reported. The relative internal turbine efficiency was determined; Re number variation was (1.1 - 1.7) x 1,000,000; turbine pressure drop, 1.25 and 1.67; gap variation, 0.15 - 7 mm. It is found that the gap (clearance) loss plays an important role in the axial part of the rotor, and only a very little role in the radial part. The gap swirl results in a gap-to-channel gas flow, and this phenomenon reduces the gas leakage around the rotor-blade tips. The above phenomenon is also enhanced by Coriolis forces. In subsequent testing of various radial turbines, it was noticed that the turbine efficiency depended only very slightly on the gap value. It is found that: (1) The gap loss is considerably lower in radial centripetal turbines than in axial turbines; hence, the gaps in radial turbines need not be very small; (2) An empirical formula has been developed for calculating the gap loss; (3) A gas-dynamic scheme is suggested to explain the low gap loss.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 09, 1967
- Accession Number
- AD0661888
Entities
People
- E. P. Krylov
- Ya. A. Spunde
Organizations
- Air Force Systems Command