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The dynamic experimental and numerical analysis of cracked beams has been studied with the aim of quantifying the influence of depth crack on the dynamic response of steel beams. Artificial Neural Method ANN has been used where a numerical simulation was improved in Matlab. A finite element model has also been developed by using the Ansys software, and the obtained results were compared with exact crack length. The study takes into account different hidden layer values in order to determine the sensitivity of the predicted crack depth. The results show that the response of the beam (frequencies) is strongly related to the crack depth, which significantly affects the beam behavior, especially when the crack is very deep where the ANN allows us to identify the crack in lower computational time. Based on the provided results, we can detect that the effect of hidden layer size can affect the results.

The dynamic experimental and numerical analysis of cracked beams has been studied with the aim of quantifying the influence of depth crack on the dynamic response of steel beams. Artificial Neural Method ANN has been used where a numerical simulation was improved in Matlab. A finite element model has also been developed by using the Ansys software, and the obtained results were compared with exact crack length. The study takes into account different hidden layer values in order to determine the sensitivity of the predicted crack depth. The results show that the response of the beam (frequencies) is strongly related to the crack depth which significantly affects the beam behavior, especially when the crack is very deep where the ANN allows us to identify the crack in lower computational time. Based on the provided results, we can detect that the effect of hidden layer size can affect the results.

In this study, numerical simulations are carried out to determine the open water performance of the INSEAN E779A marine propeller. On the other hand, modal and harmonic response analysis under hydrodynamic loading are carried out by using unidirectional approach by coupling the ANSYS Mechanical and the ANSYS CFX codes. The finite element model of the propeller has been constructed. By using this model, the dynamic characteristics of the blade have been analysed. The first 12 natural frequencies under nominal operating conditions, and the harmonic response of the exciting fluid pressures, are obtained. During Fluid-Structure Interaction, the flow around the propeller can lead to excitation of the resonance. The calculated open water performances in terms of thrust and torque coefficients correspond very well to the experimental data for a wide range of the advance coefficient. The results obtained show that the operating frequencies of the INSEAN E779A marine propeller are much lower than the resonant frequencies, so resonant conditions are easily avoided. [ABSTRACT FROM AUTHOR]

An original quasi-3D hyperbolic shear deformation theory for simply supported functionally graded plates is proposed in this work. The theory considers both shear deformation and thickness-stretching influences by a hyperbolic distribution of all displacements within the thickness, and respects the stress-free boundary conditions on the upper and lower surfaces of the plate without using any shear correction coefficient. By expressing the shear parts of the in-plane displacements with the integral term, the number of unknowns and equations of motion of the proposed theory is reduced to four as against five in the first shear deformation theory (FSDT) and common quasi-3D theories. Equations of motion are obtained from the Hamilton principle. Analytical solutions for dynamic problems are determined for simply supported plates. Numerical results are presented to check the accuracy of the proposed theory. [ABSTRACT FROM AUTHOR]