Research On Modeling And Experimentation Of Typical Plate Structures Of High-speed Aircraft By Statistical Energy Method

Plates and structures made of plates are commonly used in the field of mechanism and aerospace field. Comment measures is to apply stiffener or apply thin-varying plates so as to improve mechanical and acoustic performance of plates farther, make better use of materials and lighten the structures. Stiffened plates is a kind of programmable structure, it is easy to meet needs of mechanics and acoustics by adjusting size or distance of stiffener. Simlarly, we can adjust angles of cuneal plates to make it. As a result, it is of great meaning to study on dynamic performance of stiffened plates and thickness-varying plates. So far, there are many ways to study on stiffened plates and thickness-varying plates, such as Rayleigh-Ritz energy method,modal decomposition method and finite element method.This thesis mainly investigates on mechanical performance of stiffened plates and thickness-varying plates across high frequency range. Firstly this thesis investigate on basic concept and principle of Statistical Energy Analysis (SEA), also excellence and shortage of SEA are investigated. Secondly, this thesis research on characteristic of beams and plates from SEA aspect. As a result of scrambling of thickness-varying plates, it becomes difficult to model and analyze this kind of plates across high frequency. This thesis also study on equivalent modeling of thickness-varying plates, and experiment is made to approve it.Size, distance and type of stiffener influences stiffen plates a lot. This thesis separately study on the influence of the above-mentioned factor. And find that adjusting size, distance or type of stiffener will efficaciously improve mechanical performance of stiffened plates. What's more, this thesis research on densely alveolate stiffened plates and densely orthotropic stiffened plates, bringing forward that using orthotropic different plates to equivalently analyze them. By simulation, it's found that densely alveolate stiffened plates behave better than densely orthotropic stiffened plates on aspect of damping.