21st Congress of International Council of the Aeronautical Sciences, Melbourne, Australia, 13-18 September, 1998
Paper ICAS-98-4.1.1

PREDICTION OF ANTISYMMETRIC BUFFET LOADS ON HORIZONTAL STABILIZERS IN MASSIVELY SEPARATED FLOWS

Farokhi S., Mirsafian S., Sherwood T., Ewing M.*
Aerotech Engineering and Research Corp., U.S.A.; *University of Kansas, U.S.A.

Keywords: buffet loads, horizontal stabilizers, separated flows

A low-cost technique for the prediction of full-scale buffet loads on horizontal stabilizers of general aviation aircraft is described. A III3-scale rigid generic wind tunnel model with at-tail configuration(based on the Beech Super King Air 200) was constructed and tested at the Wichita State University 7x 10ft. Subsonic wind tunnel. The test matrix included a dynamic pressure range of 25-45 pst: an angle-of-attack range of -5-20 deg, and a sideslip range of 0-20 deg. The stabilizer was instrumented with differential pressure transducers and strain gages. The measured pressure power' spectra and cross-spectral densities were scaled and used to excite a full-scale aeroelastic finite element model which included the tail structure and aft tail cone. The computed horizontal stabilizer rolling moment power spectra are used to determine the number of exceedences (within a known probability) of a specified rolling moment level per a given maneuver( e.g .stall). Representative pressure, strain gage, and rolling moment power spectra are discussed as is a selected exceedence estimates.

view full paper