Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 16 of 16 for “"DYNAMIC STIFFNESS MATRIX"”.
-
EFFECTS OF ROTARY INERTIA AND SHEAR DEFORMATION ON EXTENSIONAL VIBRATIONS OF CONTINUOUS CIRCULAR CURVED BEAMS
<p>This dissertation is devoted to the dynamic analysis of continuous circular curved beams. The dynamic stiffness matrix is derived for the determination of natural frequencies of continuous curved beams undergoing in-plane vibrations. The formulation of stiffness matrix may be widely applied to …
-
Static, dynamic and aeroelastic behaviour of thin-walled composite structures with application to aircraft wings
… experimental investigations of the static and dynamic behaviour of thin-walled structures are carried out with the ultimate aim of improving prediction procedures for various aeroelastic phenomena. The dynamic stiffness matrix approach is used for structural idealization, while strip theory and …
-
Damage detection in structures using frequency response function (FRF) data and finite element modelling
… and damping. The resulting change in structural stiffness matrix is reflected in changes of FRF which can be exemplified by the evaluation of the damage location vector. This requires the dynamic stiffness matrix of the original undamaged structure and the frequency response curve of the …
-
Development of a statistical method for validating ESDM strain-field output
… the strain-field may be estimated from the ESDM dynamic stiffness matrix; 2) strain gages are chosen to validate the ESDM strain-fields; 3) the uncertainty of the strain gage measurements may be estimated from the uncertainty in the system calibration, the output voltage of the system and the …
-
Spectral Element Analysis of Bars, Beams, and Levy Plates
… PDE, displacement field, shape function, and dynamic stiffness matrix. A two DOF spectral Love bar element and both a four DOF spectral Euler-Bernoulli and a four DOF spectral Timoshenko beam element are also developed to gain insight into the performance of spectral elements. A cantilever …
-
Sensitivity analysis with respect to elastic boundary conditions and laser spatial variables within experimental spatial dynamic modeling
Experimental spatial dynamics modeling is a new method used to obtain a dynamic model of a harmonically excited vibrating structure. The continuous three-dimensional, complexed-valued velocity field of the structure is solved from a weighted least-squares finite element formulation, making use of …
-
Vibroacoustic analysis of panels using a wave and finite element method
… are then used to postprocess the mass and stiffness matrices of the periodic cell together with the nodal forces. The spectral dynamic stiffnesses of the fluids and structure are developed and assembled into the total spectral dynamic stiffness matrix of the coupled system. This is then …
-
Crashworthiness optimization of ultralight metal structures
This dissertation extends the use of the dynamic stiffness and transfer matrix methods in marine riser vibration. Marine risers possess a predominant chain topology. The transfer matrix method is appropriate for the analysis of such structures. Wave transmission and reflection matrices are …
-
Strong-form governing equations and solutions for variable kinematic beam theories with practical applications
… this thesis by formulating a frequency dependant dynamic stiffness matrix and using the Wittrick-Williams algorithm as solution technique. The theories developed in this thesis are validated by using some selected results from the literature. The analyses suggest that CUF furnishes a reliable …
-
Statistical Vibro-Acoustic Modelling of Nonlinear Systems with Applications in Vehicles
… system have an impact on the vehicle dynamics at high frequencies. Additionally, the response of the system can be affected by nonlinearities in the vibrations transmission path. Therefore, this research has been focused in developing computationally efficient vibro-acoustic models to …
-
The use of transfer function methods in the feedback control of distributed parameter systems
… control configurations are synthesized using the dynamic stiffness matrix method. With this method, the exact relationships of the basic elements can be combined to allow analysis of multi-input-multi-output control of more complex structures. Using this approach, examples for flexible cable and …
-
Damage identification in skeletal structures: A dynamic stiffness approach
… without any knowledge of their severity. The Dynamic Stiffness Method was chosen due to its capabilities in enabling an exact solution while facilitating addition of new elements such as springs and masses to the structure in the same way as in the approximate Finite Element Method (FEM). …
-
Aeroelastic behaviour of composite wings
… series of investigations into the structural, dynamic and aeroelastic behaviour of composite wings. The study begins with a literature review where the development of aeroelastic tailoring and specific applications of the technology are discussed in detail. A critique of methods for the …
-
Dynamic response of thin-walled composite structures with application to aircraft wings
… study first the buckling behaviour and then the dynamic characteristics of thin-walled composite structures with the presence of bending torsion coupling. The dynamic response theory incorporates the dynamic stiffness matrix approach and generalised coordinates using the normal mode method. …
-
Advances in structural dynamics, aeroelasticity and material science
… author concern his new approaches to structural dynamics, aeroelasticity, material science and related problems. In particular, the major activities of his research relate to the (i) free vibration and buckling analysis of structures, (ii) dynamic stiffness formulation, (iii) response of metallic …
-
ΠΕΙΡΑΜΑΤΙΚΟΣ-ΑΝΑΛΥΤΙΚΟΣ ΠΡΟΣΔΙΟΡΙΣΜΟΣ ΜΗΤΡΩΟΥ ΜΕΤΑΔΟΣΗΣ ΚΑΙ ΜΕΣΩ ΑΥΤΟΥ ΒΕΛΤΙΣΤΟΠΟΙΗΣΗ ΕΔΡΑΣΗΣ ΕΡΓΑΛΕΙΟΜΗΧΑΝΩΝ
… EXPERIMENTAL DETERMINATION OF THE TRANSFER MATRIX OF THE MACHINE FOUNDATION GROUND SYSTEM AND IS DESCRIBED BELOW. THE MACHINE AND THE GROUND IN THE VICINITY TO THE FOUNDATION IS SIMULATED BY A NETWORK OF NODES THAT REPRESENTS SIGNIFICANT POINTS ON THE SYSTEM'S GEOMETRY. THE FOUNDATION IS …