Finite Element Composite Simplification Modeling and Design of the Material Extrusion Wave Infill for Thin-Walled Structures

Explicit finite element method is adopted to simulate the crashworthiness performance of four types of typical thin—walled structures used in vehicle by software LS-DYNA. The structures with the same material、area and length are crash by a rigid body with 40km/h in10ms, The crash processes and crashworthiness characters are analyzed by a series crash parameters: deformation energy with unit displacement, impact force and deceleration to look for the optimal shape with crashworthiness. With comparing, the double caps section has ascendant performance than the others. The simulating methods of welded-joints are discussed to analysis their effects on crashworthiness simulation.

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An isogeometric finite element-boundary element approach for the vibration analysis of submerged thin-walled structures

Computers & Structures ◽

10.1016/j.compstruc.2021.106636 ◽

2021 ◽

Vol 256 ◽

pp. 106636

Author(s):

Alvaro del Toro Llorens ◽

Josef Kiendl

Keyword(s):

Finite Element ◽

Boundary Element ◽

Vibration Analysis ◽

Thin Walled Structures ◽

Element Approach ◽

Thin Walled ◽

Element Boundary

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Dynamic Analysis of Tapered Thin-Walled Beams Using Spectral Finite Element Method

Shock and Vibration ◽

10.1155/2019/2174209 ◽

2019 ◽

Vol 2019 ◽

pp. 1-13 ◽

Cited By ~ 2

Author(s):

Yiping Shen ◽

Zhijun Zhu ◽

Songlai Wang ◽

Gang Wang

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Wind Turbine ◽

Element Model ◽

Rotor Blades ◽

Mode Shapes ◽

Modal Frequency ◽

Thin Walled Structures ◽

Thin Walled ◽

Spectral Finite Element

Tapered thin-walled structures have been widely used in wind turbine and rotor blade. In this paper, a spectral finite element model is developed to investigate tapered thin-walled beam structures, in which torsion related warping effect is included. First, a set of fully coupled governing equations are derived using Hamilton’s principle to account for axial, bending, and torsion motion. Then, the differential transform method (DTM) is applied to obtain the semianalytical solutions in order to formulate the spectral finite element. Finally, numerical simulations are conducted for tapered thin-walled wind turbine rotor blades and validated by the ANSYS. Modal frequency results agree well with the ANSYS predictions, in which approximate 30,000 shell elements were used. In the SFEM, one single spectral finite element is needed to perform such calculations because the interpolation functions are deduced from the exact semianalytical solutions. Coupled axial-bending-torsion mode shapes are obtained as well. In summary, the proposed spectral finite element model is able to accurately and efficiently to perform the modal analysis for tapered thin-walled rotor blades. These modal frequency and mode shape results are important to carry out design and performance evaluation of the tapered thin-walled structures.

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Increasing Damping of Thin-Walled Structures Using Additively Manufactured Vibration Eliminators

Materials ◽

10.3390/ma13092125 ◽

2020 ◽

Vol 13 (9) ◽

pp. 2125 ◽

Cited By ~ 2

Author(s):

Paweł Dunaj ◽

Stefan Berczyński ◽

Karol Miądlicki ◽

Izabela Irska ◽

Beata Niesterowicz

Keyword(s):

Finite Element ◽

Dynamic Stiffness ◽

Experimental Studies ◽

Steel Beam ◽

Finite Element Models ◽

Fem Model ◽

Thin Walled Structures ◽

Resonance Frequencies ◽

Thin Walled ◽

Parametric Analyses

The paper presents a new way to conduct passive elimination of vibrations consisting of covering elements of structures with low dynamic stiffness with polylactide (PLA). The PLA cover was created in 3D printing technology. The PLA cover was connected with the structure by means of a press connection. Appropriate arrangement of the PLA cover allows us to significantly increase the dissipation properties of the structure. The paper presents parametric analyses of the influence of the thickness of the cover and its distribution on the increase of the dissipation properties of the structure. Both analyses were carried out using finite element models (FEM). The effectiveness of the proposed method of increasing damping and the accuracy of the developed FEM models was verified by experimental studies. As a result, it has been proven that the developed FEM model of a free-free steel beam covered with polylactide enables the mapping of resonance frequencies at a level not exceeding 0.6% of relative error. Therefore, on its basis, it is possible to determine the parameters of the PLA cover. Comparing a free-free steel beam without cover with its PLA-covered counterpart, a reduction in the amplitude levels of the receptance function was achieved by up to 90%. The solution was validated for a steel frame for which a 37% decrease in the amplitude of the receptance function was obtained.

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Crashing Behaviour Analysis of TWB Tubular Structures with Different Cross-Sections

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.814.159 ◽

2013 ◽

Vol 814 ◽

pp. 159-164

Author(s):

Vlad Andrei Ciubotariu

Keyword(s):

Finite Element ◽

Cross Sections ◽

Fuel Efficiency ◽

Tubular Structures ◽

Tailor Welded Blanks ◽

Thin Walled Structures ◽

Prediction And Control ◽

Thin Walled ◽

Crushing Behavior ◽

Bimetallic Structures

The present paper investigates the crashing behavior and energy absorption characteristics of thin-walled (tubular) structures with different cross-sections made from tailor welded blanks (TWB) which were subject of axial quasistatic loadings. Resulted data were obtained by using explicit nonlinear finite element code LS_Dyna V971. Implementing the TWB into the auto industry was an efficient method to decrease the general weight of different structures. By far, these kind of bimetallic structures are largely utilized in auto and naval industries because it led to important decrease of scarp quantities and general manufacturing costs, improved material use and probably the most important, great fuel efficiency. After reviewing the literature it was concluded that proper combination between mechanical characteristics of sheet metals, different thicknesses and cross-section shapes into the same thin-walled structure is far too little researched and understood. The aims of this study are better understandings of the crashing behavior regarding thin-walled structure with various cross-sections made from TWB blanks subject to quasistatic loadings. The non-linear finite element platform LS_Dyna V971 was used for the numerical analysis of the crushing behavior regarding the thin-walled structures. Having two materials constituting the thin-walled structures, the crashing behavior changed during the quasistatic loading. Thus, the crashing inertia of the structure is somehow limited and controlled. It is noted that material ratio should not be randomly chosen due to the unexpected crashing mode which could aggravate the prediction and control of the crashing behavior of the thin-walled structure.

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