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A computational study of the impingement region of an unsteady subsonic jetVertical/Short Take-Off and Landing (V/STOL) aircraft may encounter operating difficulties while hovering near the ground. Lift loss, hot gas and debris ingestion, and landing surface damage are some of the potential problems which can result from the interaction of the propulsive jets with the airframe and ground. The purpose of the present work is to develop a detailed understanding of a flowfield, a jet exiting from a flat plate impacting a ground plane, that contains much of the essential physics of the complex flows encountered by V/STOL aircraft in hover. To achieve this, a high-resolution time-accurate numerical simulation of the impinging jet flow was performed. The numerical simulation is based on the solution of the laminar compressible Navier-Stokes equations using the Beam-Warming algorithm. Complex start-up and periodic jet and jet-induced vortex structures were captured, including the formation of primary and secondary jet-induced vortices and wall-jet separation. The formation and development of these phenomena are supported by experimental measurements and smoke visualization. Results are compared with appropriate experiments.
Document ID
19900051729
Document Type
Conference Paper
Authors
Jalamani, Zakaria A. (Ohio State Univ. Columbus, OH, United States)
Nakamura, Shoichiro (Ohio State University Columbus, United States)
Van Dalsem, William R. (NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
August 14, 2013
Publication Date
June 1, 1990
Subject Category
AERODYNAMICS
Report/Patent Number
AIAA PAPER 90-1657
Funding Number(s)
CONTRACT_GRANT: NCA2-298
Distribution Limits
Public
Copyright
Other