A new and lean finite element model to predict the out of plane crash behaviour of aluminium honeycomb structures

Squeeze film damping has a significant effect on the dynamic response of MEMS devices that employ perforated microstructures with large planar areas and small gap widths separating them from the substrate. Perforations can alter the effect of squeeze film damping by allowing the gas underneath the device to easily escape, thereby lowering the damping. By decreasing the size of the holes, the damping increases and the squeeze film damping effect increases. This can be used to minimize the out-of-plane motion of the microstructures toward the substrate, thereby minimizing the possibility of contact and stiction. This paper aims to explore the use of the squeeze-film damping phenomenon as a way to mitigate shock and minimize the possibility of stiction and failure in this class of MEMS devices. As a case study, we consider a G-sensor, which is a sort of a threshold accelerometer, employed in an arming and fusing chip. We study the effect of changing the size of the perforation holes and the gap width separating the microstructure from the substrate. We use a multi-physics finite-element model built using the software ANSYS. First, a modal analysis is conducted to calculate the out-of-plane natural frequency of the G-sensor. Then, a squeeze-film damping finite-element model, for both the air underneath the structure and the flow of the air through the perforations, is developed and utilized to estimate the damping coefficients for several hole sizes. Results are shown for various models of squeeze-film damping assuming no holes, large holes, and assuming a finite pressure drop across the holes, which is the most accurate way of modeling. The extracted damping coefficients are then used in a transient structural-shock analysis. Finally, the transient shock analysis is used to determine the shock loads that induce contacts between the G-sensor and the underlying substrate. It is found that the threshold of shock to contact the substrate has increased significantly when decreasing the holes size or the gap width, which is very promising to help mitigate stiction in this class of devices, thereby improving their reliability.

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Forming limit diagrams by including the M–K model in finite element simulation considering the effect of bending

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/1464420716642258 ◽

2016 ◽

Vol 232 (8) ◽

pp. 625-636 ◽

Cited By ~ 20

Author(s):

Mostafa Habibi ◽

Ramin Hashemi ◽

Ahmad Ghazanfari ◽

Reza Naghdabadi ◽

Ahmad Assempour

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Metal Forming ◽

Forming Limit Diagram ◽

Element Model ◽

Forming Limit ◽

Finite Element Models ◽

Element Simulation ◽

Simple Tension ◽

Out Of Plane

Forming limit diagram is often used as a criterion to predict necking initiation in sheet metal forming processes. In this study, the forming limit diagram was obtained through the inclusion of the Marciniak–Kaczynski model in the Nakazima out-of-plane test finite element model and also a flat model. The effect of bending on the forming limit diagram was investigated numerically and experimentally. Data required for this simulation were determined through a simple tension test in three directions. After comparing the results of the flat and Nakazima finite element models with the experimental results, the forming limit diagram computed by the Nakazima finite element model was more convenient with less than 10% at the lower level of the experimental forming limit diagram.

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NON LINEAR DYNAMIC ANALYSIS OF THIN-WALLED STRUCTURES ADOPTING A MIXED BEAM FINITE ELEMENT MODEL WITH OUT-OF-PLANE CROSS-SECTION WARPING

Proceedings of the 7th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015) ◽

10.7712/120119.7174.19248 ◽

2019 ◽

Cited By ~ 1

Author(s):

Paolo Di Re ◽

Daniela Addessi ◽

Achille Paolone

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Dynamic Analysis ◽

Cross Section ◽

Element Model ◽

Linear Dynamic ◽

Thin Walled Structures ◽

Mixed Beam ◽

Out Of Plane ◽

Thin Walled

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Riveted Hull Joint Design in RMS Titanic and Other Pre—World War I Ships

Marine Technology and SNAME News ◽

10.5957/mt1.2003.40.2.82 ◽

2003 ◽

Vol 40 (02) ◽

pp. 82-92

Author(s):

Richard Woytowich

Keyword(s):

Finite Element ◽

World War I ◽

Finite Element Model ◽

Plate Thickness ◽

Element Model ◽

World War ◽

Joint Construction ◽

Riveted Joints ◽

Riveted Joint ◽

Out Of Plane

Beginning with an overview of riveted joint construction, this paper shows that the efficiency of riveted joints in pre-World War I ships decreased as plate thickness increased. In the case of the RMS Titanic, some of the joints involved in the iceberg impact were only about 27% as strong as the plates they connected. A finite element model is used to show how such a joint would respond to the sort of out-of-plane load that the iceberg would have applied. For one possible load configuration, the joint failure is recreated. Finally, although Titanic and her sisters were not built to class, the design of the riveted joints is examined in the context of relevant Lloyd's Register of Shipping Rules.

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Stochastic finite element model error for unreinforced masonry walls subjected to one way vertical bending under out-of-plane loading

Brick and Block Masonry - From Historical to Sustainable Masonry ◽

10.1201/9781003098508-17 ◽

2020 ◽

pp. 144-151

Author(s):

A.C. Isfeld ◽

M.G. Stewart ◽

M.J. Masia

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Element Model ◽

Model Error ◽

Unreinforced Masonry ◽

Masonry Walls ◽

Stochastic Finite Element ◽

Out Of Plane

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Out-of-Plane Stability Analysis of U-Section Pin-End Steel Arch

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.351-352.169 ◽

2013 ◽

Vol 351-352 ◽

pp. 169-173

Author(s):

Kuan Tang Xi ◽

Jin Li ◽

Tie Gang Zhou ◽

Qing Xing Xu

Keyword(s):

Finite Element ◽

Stability Analysis ◽

Finite Element Model ◽

Element Model ◽

Load Models ◽

Out Of Plane ◽

Radial Loading ◽

Better Than

Two kinds of finite element model which can reflect the effects of different loading positions were constructed with Beam 188 and Shell 181. Effects of different restraints, load models and rise-span ratios on out-of-plane buckling were studied by comparing results of fixed arches with that of pin-end arches under three loading models. It is conservative to design by employing results of radial loading. As for out-of-plane stability, pin-end arches are better than fixed arches when rise-span ratio is big. Compared with U-section pin-end circular arches with diaphragm, those with batten plates have batter out-of-plane stability, and they are more economical and easier to construct.

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Analysis and design of laterally unsupported portal frames for out-of-plane stability

Canadian Journal of Civil Engineering ◽

10.1139/l04-002 ◽

2004 ◽

Vol 31 (3) ◽

pp. 440-452 ◽

Cited By ~ 7

Author(s):

Ilian Zinoviev ◽

Magdi Mohareb

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Potential Energy ◽

Finite Element Model ◽

Element Model ◽

Element Analysis ◽

Analysis And Design ◽

Axial Forces ◽

Eigen Value ◽

Out Of Plane

A methodology for the analysis and design of laterally unsupported portal frames is proposed. A finite element model is developed to predict the elastic critical load and associated buckling mode. Regression analysis is then conducted to find lateral displacement and rotation field expressions that closely approximate the buckled configurations predicted by the finite element analysis. The obtained functions are then substituted into the total potential energy expression, and the stationarity conditions are evoked. The resulting eigen-value problem is solved for the out-of-plane buckling loads that are then compared with those based on the finite element model. The agreement between the two solutions provides an indication of the accuracy of the simplified energy solution. The member destabilizing effects induced by axial forces are separated from those induced by strong axis bending. The separation of these two effects is subsequently exploited in a two-step eigen-value procedure, aimed at determining the key member resistances defined in the interaction check of the standard CSA-S16-01, while accurately modeling the boundary conditions of the member. These are (i) compressive resistance of the member in the absence of bending effects and (ii) flexural resistance of the member in the absence of axial force effects.Key words: portal frames, lateral buckling, finite element analysis, wide flange sections, frame design, principle of stationary potential energy.

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Out-of-Plane Stability Analysis of I-Section Steel Arch

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.781 ◽

2013 ◽

Vol 405-408 ◽

pp. 781-785

Author(s):

Kuan Tang Xi ◽

Jin Li ◽

Tie Gang Zhou ◽

Tao Lin

Keyword(s):

Finite Element ◽

Stability Analysis ◽

Finite Element Model ◽

Element Model ◽

Buckling Loads ◽

Load Models ◽

Out Of Plane ◽

Radial Loading ◽

Better Than

Finite element model which can reflect the effects of different loading positions were constructed with Beam 188. Effects of different restraints, load models and rise-span ratios on out-of-plane buckling were studied by comparing results of fixed arches with that of pin-end arches under three loading models. It is conservative to design by employing results of radial loading. For ideal restraints, out-of-plane stability of pin-end arches is better than fixed arches when rise-span ratio is big. Effects of different loading positions on out-of-plane buckling were studied. Buckling loads of arches which are loaded at arch-axises are bigger than those of top flanges, but smaller than those of bottom flanges.

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Stress analysis of shielding electrode in chip with pressure sensor embedded in accelerometer

Microelectronics International ◽

10.1108/mi-10-2017-0056 ◽

2019 ◽

Vol 36 (1) ◽

pp. 35-42 ◽

Cited By ~ 1

Author(s):

Chun-Lin Lu ◽

Meng-Kao Yeh

Keyword(s):

Residual Stress ◽

Finite Element ◽

Finite Element Model ◽

Stress Analysis ◽

Glass Substrate ◽

Pressure Sensors ◽

Element Model ◽

Content Type ◽

Out Of Plane ◽

The Finite Element Model

Purpose Analysis of the thermal effects during the packaging process or in the actual operating environment is necessary to develop small monolithic integrated sensing chips with heterogeneous integration. The use of multiple layers and various materials in monolithic integrated sensing chips addresses the coefficient of thermal expansion (CTE) mismatch issue. The purpose of this study is to focus on the residual stress analysis of the shielding electrode, which is a metal film that prevents pull-in of proof-mass during anodic bonding in microelectromechanical system (MEMS) chips with pressure sensors embedded in an accelerometer. Design/methodology/approach The finite element model of the chip was built by the commercial software ANSYS, and the residual stress was evaluated during the die attachment process for the shielding electrode. Various shielding electrode materials and a proposed design with a keep-out zone to reduce the residual stress are discussed, with a focus on the relationship between the geometric parameters of the chip and the residual stress for copper shielding electrodes of different thicknesses. Findings The results of the finite element analysis showed that the use of polysilicon as a shielding electrode in the proposed design generated the lowest residual stress because of its low CTE. The maximum stresses in both of in-plane and out-of-plane directions in the finite element model were reduced by keep-out zone design for the proposed design of the copper shielding electrode, and had 11 times reduction in out-of-plane direction especially, according to the nonlinear analysis as the stress concentration point in the shielding electrode moved. Moreover, the design with a thinner shielding electrode, thinner glass substrate and higher CTE of the glass substrate also lowered the maximum von Mises stress. On the other hand, the stress level during the operating temperature, without considering residual stress, overestimated up to five times in the proposed design. Originality/value In this study, valuable suggestions are proposed for the design of chips with pressure sensors embedded in accelerometers.

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A Finite Element Model for Simulating Out-of-Plane Behavior of Masonry Infilled RC Frames

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.166-169.849 ◽

2012 ◽

Vol 166-169 ◽

pp. 849-852 ◽

Cited By ~ 2

Author(s):

Chang Hai Zhai ◽

Jing Chang Kong ◽

Xiao Hu Wang

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Interaction Model ◽

Material Model ◽

Element Model ◽

Plane Failure ◽

Rc Frames ◽

Out Of Plane ◽

Infilled Rc Frames ◽

Masonry Infilled Rc Frames

The in-plane seismic performance has been studied by many researchers all over the world, whereas few studies have been done on the out-of-plane behavior of the infilled RC frames. In this paper, a separate finite element model for simulating the out-of-plane failure mode and capacity of masonry-infilled RC frames is developed using 3-D elements with damage-plasticity material model and the surface-based contact cohesive interaction model simulating the interface between blocks. Comparison between the results of analysis and experiment indicates that the present model can successfully simulate the out-of-plane behavior of the structure.

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