The performance of V/STOL aircraft is influenced significantly by ground effects during landing and takeoff when the propulsive flow of the aircraft is directly dowward. To mitigate downwash effects, a new landing mat concept was developed at Civil Engineering Laboratory whereby exhaust flow is controlled by either a very thin array of diamond patterns or parallel ribs. The impinging jet flow aligns itself with the long axis of the grid pattern, expanding in two directions along a single line rather than radially outward over the plane of the ground. Grid height or thickness is small compared with jet diameter. A method for calculating grid height was developed by combining Froessling's solution for boundary layer thickness and Glauert's solution for wall jet thickness. (Author)
Reduction of V/STOL Downwash Effects by Jet Exhuast Flow Control
1975
54 pages
Report
Keine Angabe
Englisch
Consideration of V/STOL downwash and ground environment
Engineering Index Backfile | 1968
|Consideration of V/STOL Downwash and the Ground Environment
SAE Technical Papers | 1968
|Online Contents | 1999
AIAA | 1980
|