Analysis Of Vibration Characteristics Of Composite Rotating Plate And Shell Structures Under Elastic Boundary Conditions

Compared with other single materials,composite materials have better performance in stiffness and strength,longer fatigue life and resistance to electrochemical corrosion.In recent years,composite materials have attracted more and more attention in aircraft design,shipbuilding,petrochemical container design and other engineering fields.As the basic element of engineering structures,the research on the vibration characteristics of composite laminated plates and shells structures are of great practical significance for the development of related fields.At present,most researches focus on the thick plates and shells and the thin plate-shell coupling structures under the classical boundary conditions.However,in the field of engineering application,there are a large number of composite rotating laminated plates,shells and their coupling structures with the thickness from thin to medium,and the structures are often under elastic boundary conditions.Therefore,relevant researches have certain theoretical guiding significance for practical engineering applications.In this paper,a mechanical model for the study of the vibration characteristics of composite rotating laminated plates and shells in the transition stage from thin to medium thickness under elastic boundary conditions is established.On the basis of the simplified first order shear deformation theory,with the improved Fourier series to approximate representation structure of allowable displacement function,obtained the mathematical model of the rotating composite laminated plates,laminated cylindrical shells,laminated conical shells and plates-shells coupling structures vibration characteristics.Decorating artificial virtual spring through the coupling boundary,the continuity requirements was satisfied,and the direct transformation of structure is realized.Then the classical boundary conditions and elastic boundary conditions are simulated by distributing boundary springs evenly on the boundary of the structure.Then,Rayleigh-ritz energy method is used to establish the vibration characteristic analysis model and solve the equations,and finally the required frequencies and modes are obtained.By comparing the results of this paper with those of the references,the results of the finite element simulation software and the results of the modal test experiment,the accuracy and fast convergence of the vibration characteristic analysis model established in this paper with the transition stage from thin to medium thickness are verified.In addition,the free vibration characteristics are analyzed based on the paramaetric models of rotating composite laminated plates,cylindrical shells,conical shells and laminated rotating plates-cylindrical shells coupling structures.The influence of the different geometric and material parameters,boundary conditions,laying angles and laminated modes on the structure natural frequency is discussed,which can provide certain theoretical basis and technical support for the related structure design process.