Análise do comportamento dinâmico de vigas sanduíche com núcleo honeycomb preenchido com gel magneto reológico

Abstract

With the rapid advancement of technology comes the need for lighter weight and higher strength materials, so studies on new materials and manufacturing techniques are needed. The aeronautics industry is always at the forefront of researching new materials, where the weight factor is crucial. In contrast, aircraft suffer from intense mechanical vibration and the ability to control these vibrations is of paramount importance for stability. of the aircraft and its structural integrity. To control these intense vibrations, intelligent materials have been pointed as a possible resource for vibration control, since it is possible to vary the modal frequencies of the structure through electrical or magnetic excitations. The objective of this dissertation is to analyze the dynamic behavior under the influence of vibrations in sandwich beams, which have honeycomb cores filled with rheological magnet gels and composite material skins. The development of the work has an experimental analysis through free and forced vibration tests to determine the modal parameters of the beams built according to the applied magnetic field intensity, and a statistical analysis to determine the factors that most impacted this process. With the results obtained, the use of these materials is promising in structures, due to the fact that they achieve reductions in the value of natural frequencies in the order of 54%, increase in damping factors of up to 390% and decrease in forced vibration amplitude of 40%. % in relation to the use of a magnetic field. Resulting from the statistical analysis showed that the factor that most influenced the response of free and forced vibration assays was the gel. In the conclusion of this dissertation, it is proposed new models of beams, since there are few studies in the honeycomb core filled with rheological magnet gel.