Accession Number : AD0286834

Title :   AN EXPERIMENTAL INVESTIGATION OF THE RANDOM EXCITATION OF A TAILPLANE SECTION BY JET NOISE

Corporate Author : SOUTHAMPTON UNIV (ENGLAND)

Personal Author(s) : CLARKSON,B.L. ; FORD,R.D.

Report Date : JUL 1962

Pagination or Media Count : 1

Abstract : The response of a section of tailplane structure to both discrete and random noise pressures was studied in detail. Initially the specimen was mounted behind a jet engine and the induced strains were analyzed with the object f determining both the resonant frequencies and the corresponding modes of vibration. During these tests a survey was made of the spectrum and correlation pattern of the jet noise on the surface of the model. Secondly the specimen was mounted in front of a loudspeaker in an acoustics laboratory and the structural resonances were excited by means of discrete frequency sound. The mode shapes were studied in detail with the aid of a stroboscope. The tailplane skin on this particular piece of structure only responds to any significant degree in one structural mode. Although reasonable comparison was obtained between the random and discrete tests, it was not possible to calculate the induced stresses using the observed mode shapes and measured pressure excitation. (Author)

Descriptors :   *TAILS (AIRCRAFT), AIRFRAMES, FREQUENCY, JET ENGINE NOISE, JET AIRCRAFT, PRESSURE, RESONANCE, STRESSES, STROBOSCOPES, TESTS, VIBRATION

Distribution Statement : APPROVED FOR PUBLIC RELEASE