Comparative study of finite element analysis and geometrically exact beam analysis of a composite helicopter blade

Date

2018

Author

Ataç, Meryem Nisa

Metadata

Show full item record

Item Usage Stats

242
views

0
downloads

In this master thesis, comparative study of the finite element analysis and geometrically exact beam analysis of a composite helicopter blade is performed. The objective of this study is to investigate the applicability of the geometrically exact beam analysis of the composite helicopter blade in predicting the structural response of the composite blade. To evaluate the structural response determined by the geometrically exact beam analysis of the composite blade, detailed finite element model of the blade is prepared and the structural response of two methods are compared for different static and transient load cases and dynamic analysis. Geometrically exact beam analysis utilizes variational asymptotic beam section analysis for the calculation of sectional stiffness and mass matrices, and general deformation of the blade for the static and transient load cases can be determined with high accuracy. Three dimensional stresses in the selected blade sections can also be determined via the stress recovery feature of the variational asymptotic beam section method. It is shown that the neutral axis, shear center, still air natural frequency, static and transient displacement and static stress analysis results determined by the geometrically exact beam analysis match perfectly with the finite element analysis results for the rectangular section and airfoil section blade models studied. It is considered that especially for the structural design of the airfoil sections of the blade, which requires many re-analyses due to frequent design changes in the detailed design stage, geometrically exact beam analysis can replace finite element method which requires longer modelling times to reflect the design changes.

Subject Keywords

Blades., Helicopters., Composite materials., Finite element method.

URI

http://etd.lib.metu.edu.tr/upload/12621870/index.pdf
https://hdl.handle.net/11511/27126

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Failure analysis of tapered composite structures under tensile loading Çelik, Ozan; Parnas, Kemal Levend; Department of Mechanical Engineering (2016) A three dimensional finite element modeling approach is used to evaluate the effects of preliminary design variables on the performance of tapered composite laminates under tensile loading. Hashin failure criteria combined with a progressive failure algorithm is used for in-plane failure mechanisms and cohesive zone method is used for out-of-plane failures. The modeling approach is validated by a comparison with experimental results from literature. The validated model is used to examine various design vari...
Nonlinear fiber modeling of steel-concrete partially composite beams with channel shear connectors Öztürk, Alper; Baran, Eray; Department of Civil Engineering (2017) The purpose of this study is to develop a nonlinear fiber-based finite element model of steel-concrete composite beams. The model was developed in OpenSees utilizing the available finite element formulations and the readily available uniaxial material constitutive relations. The model employed beam elements for the steel beam and the concrete slab, while zero-length connector elements were used for the steel-concrete interface. The channel shear connector response used in numerical models was based on the p...
Experimental and numerical failure analysis of advanced composite structures with holes Atar, Mehmet Bilal; Parnas, Kemal Levend; Department of Mechanical Engineering (2016) In this work, a design methodology for advanced composite structures with holes is presented. A three dimensional finite element model (FEM) is constructed to simulate such a structural application similar to weight-pockets in helicopter blades. Material properties are obtained by a material characterization study. The progressive failure method with FEM is used for the material degradation. In order to induce delamination in simulation, cohesive layers are implemented between composite layers. Results are ...
Reduced order modeling of helicopter substructures for dynamic analysis Hayırlı, Uğur; Kayran, Altan; Department of Aerospace Engineering (2018) Dynamic analysis of a structure is generally conducted by the finite element method in aerospace structures. The models usually contain large number of elements to be able to obtain more accurate results. Although the most computers are capable of solving the large and complex problems, the analysis problems such as dynamic optimization, aeroelastic, frequency and time response may take long time due to involving iterative and multi-step processes. In this study, various model reduction methods are describe...
COMPARATIVE STRUCTURAL OPTIMIZATION STUDY OF COMPOSITE AND ALUMINUM HORIZONTAL TAIL PLANE OF A HELICOPTER Arpacıoğlu, Bertan; Kayran, Altan (2019-11-11) This work presents structural optimization studies of aluminum and composite material horizontal tail plane of a helicopter by using MSC. NASTRAN SOL200 optimization capabilities. Structural design process starts from conceptual design phase, and structural layout design is performed by using CATIA. In the preliminary design phase, study focuses on the minimum weight optimization with multiple design variables and similar constraints for both materials. Aerodynamic load calculation is performed using ANSYS ...

Citation Formats

M. N. Ataç, “Comparative study of finite element analysis and geometrically exact beam analysis of a composite helicopter blade,” M.S. - Master of Science, Middle East Technical University, 2018.