J.C. Deel, J.M. Komrower

Modal analysis assumes that the test structure can be approximated to a useful degree of accuracy by a linear model. This approximation is never exact, and many cases of practical interest show considerable deviation from linear behavior. After a brief review of some recent efforts to extend the use of modal analysis further into the nonlinear domain, this paper proposes a systematic approach to the choice of test methodologies based on analysis of test objectives combined with some simple preliminary tests. The term "moderate nonlinearity" is defined here to mean that a useful linear model exists, and that its parameters vary smoothly over some specified range of loading conditions. Even if the test structure itself is only moderately nonlinear, there is no guarantee that the test methods employed will arrive at the correct best linear model. The remainder of the paper compares how well various test methods perform in a moderately nonlinear test case. These examples also illustrate practical methods for identifying nonlinearity in the test data and for assessing if it can be considered "moderate" in this sense.

International Forum on Aeroelasticity and Structural Dynamics 1991, Aachen

Conference Paper

englisch

21,0 x 29,7 cm, 9 Seiten

DGLR-Bericht, 1991, 1991-06, International Forum on Aeroelasticity and Structural Dynamics 1991 Proceedings; S.186-194; 1991; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

aeroelasticity

Bestellbar

1991