INFLUENCE OF STRUCTURAL CHANGES OF A RADIAL-AXIAL HYDROTURBINE ON ITS CAVITATION.
Abstract
In bushing cavitation one can include: (a) bushing diffusion cavitation; (b) bushing cavitation of irregularities of the bushing surface; (c) bushing cavitation of discharge holes and (d) bushing axial cavitation, caused by rotation of the flow. In turbines without discharge holes in the bushing, the most dangerous with respect to the appearance of cavitation will be cavitation due to irregularities on the surface of the bushing. In turbines with discharge holes the most dangerous will be cavitation of the discharge holes, appearing during flowing around of the inlet edges of the holes. Zones of various forms cavitation take different forms during their propagation in the draft tube. During normal exit, even outside the region of optimum eta, the zone of cavitation disintegrates in the flow into separate bubbles. During regimes with swirling outflow, trains of zones cavitation on the bushing merge into filaments and are drawn closer to the axis of rotation of the column of liquid in the draft tube. But the axis of rotation of filaments does not coincide with the axis of the tube, as a consequence of which spiral filaments are formed. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1966
- Accession Number
- AD0637444
Entities
People
- I. V. Kotenev
- K. K. Shalnev
Organizations
- National Air and Space Intelligence Center