Design of a cutting head for a crosscutting machine

The present paper deals with the structural analysis and the re-design of a cutting head for an automatic crosscutting machine. The machine is already marketed, and can process rectangular section wooden slats. The principal goal of this work is to develop a new mechanism capable of enhancing the productivity of the machine by around 80%. The work has been carried out by means of both numerical finite element analysis tools and analytical models. In fact, a secondary aim of the research is to define an analytical model which can capture the dynamic behavior of the device: this tool will be helpful to the design engineer in order to save costs associated with the development of future head designs.

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Effect of Ply Stacking Sequence on Structural Response of Symmetric Composite Laminates

Volume 10: Micro- and Nano-Systems Engineering and Packaging ◽

10.1115/imece2014-37217 ◽

2014 ◽

Author(s):

Mosfequr Rahman ◽

Saheem Absar ◽

F. N. U. Aktaruzzaman ◽

Abdur Rahman ◽

N. M. Awlad Hossain

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Analytical Model ◽

Composite Laminates ◽

Structural Response ◽

Laminated Composite ◽

Analytical Models ◽

Orthotropic Materials ◽

Stacking Sequence ◽

Element Analysis

In this work, the effect of ply stacking sequence on the structural response of multi-ply unidirectional fiber-reinforced composite laminates was evaluated using finite element analysis. The objective of this study was to develop a computational model to analyze the stress response of individual plies in a composite laminate for a given stacking sequence. A laminated composite plate structure under tensile loading was modeled in ANSYS. Stress profiles of the individual plies were obtained for each lamina. An Epoxy matrix with both unidirectional Graphite and Kevlar fibers was considered for the model. Three dimensional sectioned shell elements (SHELL181) were used for meshing the model. Several sets of stacking sequences were implemented, symmetrical to the mid-plane of the laminate. Symmetric stacking configurations of 6 layers stacked in ply angles of [0/45/-45]s, [0/60/-60]s, [0/45/90]s, and an 8-layered arrangement of [0/45/60/90]s were modeled for the analysis. The layer thickness was maintained at 0.1 mm. The results were compared against an analytical model based on the generalized Hooke’s law for orthotropic materials and classical laminate theory. A numerical formulation of the analytical model was implemented in MATLAB to evaluate the constitutive equations for each lamina. The stress distributions obtained using finite element analysis have shown good agreement with the analytical models in some of the cases.

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Structural Analysis of Centrifugal Fan Impeller Using CATIA Software

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.809-810.859 ◽

2015 ◽

Vol 809-810 ◽

pp. 859-864

Author(s):

Dănuţ Zahariea

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Structural Analysis ◽

Design Methods ◽

Constant Thickness ◽

Blade Design ◽

Centrifugal Fan ◽

Element Analysis ◽

The Finite Element Analysis ◽

Modes Of Vibration

In this paper, the finite element analysis for stress/deformation/modes of vibration for the centrifugal fan impeller with constant thickness backward-curved blades using CATIA software will be presented. The principal steps of the finite element analysis procedure using CATIA/Generative Structural Analysis environment will be presented: creating the 3D model; configuring the mesh; applying the restraints; applying the loads; running the numerical static analysis and the numerical frequency analysis; interpreting the results and observing the modes of vibration correlating with the impeller mode shape. This procedure will be used for 4 different centrifugal fan impellers according with the 4 blade design methods and the results will be comparatively analyzed. For each design method, two materials will be used: steel with density of 7860 kg/m3 and aluminium with density of 2710 kg/m3. Two important results have been obtained after the structural analysis: under the working conditions considered for the analysis, all 4 blade design methods leads to impellers with very good mechanical behaviour; any frequency of the main modes of vibrations for all blade design methods and for both materials is not in phase with the impeller speed, thus the possibility of resonance being eliminated.

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