Accession Number : AD0284886

Title :   Further Analysis of the Random Vibrations of the Caravelle Test Section.

Corporate Author : SOUTHAMPTON UNIV (ENGLAND)

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

Report Date : JUL 1962

Pagination or Media Count : 1

Abstract : Further tests were made on the Caravelle aircraft test section. The vibrations, induced by jetnoise, of a row of eight panels in the side of the rear fuselage were analyzed and it was confirmed that the skin panels tend to vibrate in fundamental modes with adjacent panels out of phase with each other so causing the intermediate stringers to twist. Due, presumably, to variations in the panel sizes, no more than three panels were observed to couple in such a mode. The vibrations of the panels on the upper surface of the outboard elevator were also analyzed. It was found that the ribs act as stiff supports but the vibrations of the two panels between any pair of ribs are coupled in the lower-frequency modes. The mode shapes were not satisfactorily determined owing to lack of sufficient strain-gauges on the panels, but it is deduced that the stresses in the ribs are caused by direct inertia loading from the supported panels. (Author)

Descriptors :   *AIRFRAMES, *JET ENGINE NOISE, *METAL PLATES, *VIBRATION, ACOUSTICS, FATIGUE (MECHANICS)

Distribution Statement : APPROVED FOR PUBLIC RELEASE