PATTERNS OF FLOW UNDER A TWO-DIMENSIONAL GEM
Abstract
An experimental study of a two-dimensional annular jet directed against a nearby ground surface is presented. The experiments were carried out at sufficiently high Reynolds numbers for the viscous influence to be negligible, and primary attention was given to the geometry of the mean streamlines as the boundary geometry was changed. The flow pattern was that of diffusing jets which are deflected laterally by their interaction with the central pressure zone. Though standing eddies were observed to exist under the nozzle base, their effect upon the pressure distribution was small. Both the exit angle (E) and the ratio of nozzle gap to altitude (G/H) were found to be important in jet performance. An evaluation was also made of the augmentation factor (A), which is defined as the ratio of total lift to the total jet momentum flux, and the optimum values of (E) and (G/H) were shown to correspond to the optimum value of (A). (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1962
- Accession Number
- AD0272232
Entities
People
- Ben-chie Yen
Organizations
- University of Iowa