Vibration Analysis Of A Composite Stiffened Beam With A Co-cured Multilayer Damping Film Embedded

Co-cured Multi-layer Damping Films Embedded Composite Material Beam Structure(CMDFECMBS)has many advantages of light weight,strong bearing capacity,high damping,fatigue resistance,vibration reduction and noise reduction.Therefore,it has a wide application prospect in aviation,navigation and land transportation.Based on the theoretical calculation,the vibration equation of mono-layer,double-layer and three-layer damping films embedded composite beam and double-layer damping films embedded composite stiffened beam is derived in this paper,and the vibration analysis is carried out.The validity of the theoretical model is verified by the combination of experimental verification with numerical simulation.Furthermore,the distribution of damping layer in composites and the influence of geometric parameters on CMDFECMBS dynamic properties are explored.The main innovations and work are as follows:(1)Combining the first-order shear deformation theory,variational principle and Hamilton principle,the free vibration model of mono-layer,double-layer and three-layer damping films embedded composite beam is established.A theoretical solution of free vibration of the model under fixed-fixed boundary conditions is presented by using Galerkin method.The vibration characteristics of mono-layer,double-layer and threelayer damping films embedded composite beams are obtained,and the vibration problem of co-curing multi-layer damping films embedded composite beams under fixedsupported boundary is solved theoretically.(2)The experimental platform is built,the multi-layer damping embedded composite beam specimens are manufactured,and the theoretical solution is compared with the experimental results to verify the validity of the theoretical model.Finally,the distribution of damping layer and the influence of geometric parameters on the dynamic properties of multi-layer damping films embedded composite beams are further explored.(3)A theoretical model of double-layer damping films emedded composite beam with stiffening is established.Based on the relevant boundary conditions and the Galerkin method,the vibration characteristics of stiffened beams under the fixed-supported boundary are obtained.The validity of the theoretical model is verified by numerical simulation method,and the vibration problem of the stiffened beam under the fixed support boundary is solved theoretically.Conclusion provides a theoretical basis for the wide application of large damping and high stiffness composite structure.