Separation force analysis and prediction based on cohesive element model for constrained-surface Stereolithography processes

A framework based on a complex dynamical system viewpoint for formulating and solving dynamic ice-structure interaction problems is introduced. Important constituents required for formulating a well posed initial-boundary value problem are discussed. Significance of these constituents is illustrated using a Cohesive Element model of several example problems.

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A cohesive element model for mixed mode loading with frictional contact capability

International Journal for Numerical Methods in Engineering ◽

10.1002/nme.4398 ◽

2012 ◽

Vol 93 (5) ◽

pp. 510-526 ◽

Cited By ~ 46

Author(s):

Leonardo Snozzi ◽

Jean-François Molinari

Keyword(s):

Mixed Mode ◽

Frictional Contact ◽

Element Model ◽

Cohesive Element ◽

Mixed Mode Loading ◽

Cohesive Element Model

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Parameter Sensitivity in Numerical Modelling of Ice-Structure Interaction With Cohesive Element Method

Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology ◽

10.1115/omae2016-54687 ◽

2016 ◽

Cited By ~ 3

Author(s):

Dianshi Feng ◽

Sze Dai Pang ◽

Jin Zhang

Keyword(s):

Element Model ◽

Offshore Structures ◽

Parameter Sensitivity ◽

The Arctic ◽

Cohesive Element ◽

Structure Interaction ◽

Marine Structure ◽

Ice Loads ◽

The Stability ◽

Element Method

The increasing marine activities in the Arctic has resulted in a growing demand for reliable structural designs in this region. Ice loads are a major concern to the designer of a marine structure in the arctic, and are often the principal factor that governs the structural design [Palmer and Croasdale, 2013]. With the rapid advancement in computational power, numerical method is becoming a useful tool for design of offshore structures subjected to ice actions. Cohesive element method (CEM), a method which has been widely utilized to simulate fracture in various materials ranging from metals to ceramics and composites as well as bi-material systems, has been recently applied to predict ice-structure interactions. Although it shows promising future for further applications, there are also some challenging issues like high mesh dependency, large variation in cohesive properties etc., yet to be resolved. In this study, a 3D finite element model with the use of CEM was developed in LS-DYNA for simulating ice-structure interaction. The stability of the model was investigated and a parameter sensitivity analysis was carried out for a better understanding of how each material parameter affects the simulation results.

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The Analysis of Horizontal Extension Capability in Horizontal Wells

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1010-1012.1745 ◽

2014 ◽

Vol 1010-1012 ◽

pp. 1745-1749

Author(s):

Wei Kai Liu ◽

Ming Xing Song ◽

Zi Yi Xu ◽

Xue Hong Zhang

Keyword(s):

Drag Force ◽

Field Data ◽

Horizontal Wells ◽

Element Model ◽

Force Analysis ◽

Gap Element ◽

Field Works ◽

Set Up

It is critical to understand whether the available drilling assembly could meet the requirements of drilling design during the design and drilling of horizontal wells. This paper pointed out several limitations on horizontal extension capability of horizontal wells and provided judging criteria of the limit of horizontal extension based upon the characteristics of horizontal wells, and set up the gap element model analyzing torque and dragged of whole drill strings in horizontal wells. According to the force analysis of drill strings in bores given the foundation for regularities in the distribution of torque and drag force along the axis, on the basis of those above mentioned models and theories, a software was made to calculate the torque and drag force of a well, which compared with the field data, the average discrepancies of theoretical values are below 20% that could meet the needs in field works.

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Numerical Simulation of Ice Action to a Lighthouse

Volume 5: Polar and Arctic Sciences and Technology; CFD and VIV ◽

10.1115/omae2009-80164 ◽

2009 ◽

Cited By ~ 2

Author(s):

Arne Gu¨rtner ◽

Morten Bjerka˚s ◽

Walter Ku¨hnlein ◽

Peter Jochmann ◽

Ibrahim Konuk

Keyword(s):

Outer Boundary ◽

Element Model ◽

Computational Method ◽

Ice Thickness ◽

Cohesive Elements ◽

Element Mesh ◽

To The Lighthouse ◽

Ice Loads ◽

Qualitative Observation ◽

Cohesive Element Model

Ice actions to the Norstro¨msgrund lighthouse are simulated by means of the computational cohesive element model. The numerical model is developed in the framework of finite elements. Fracture of the ice sheet is accounted for by the cohesive elements placed at internal finite element mesh boundaries in order to track traction versus separation. One single ice event on the Norstro¨msgrund lighthouse is selected for which the ice loads as well as outer boundary conditions are recorded. This event serves as a basis for comparison to the computational method presented in this paper. The simulation results indicate that the proposed numerical method captures many of the qualitative observation as well as quantitatively derives comparable global ice loads to the lighthouse to those of the selected ice event. Future analysis should include additional validation to variations in ice thickness and drift speed.

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The Rolling Force Analysis of Closed Ring Rolling High-Neck Flange

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.201-202.1130 ◽

2012 ◽

Vol 201-202 ◽

pp. 1130-1134

Author(s):

Wen Fei Peng ◽

Jing Jing Liang ◽

Xue Dao Shu ◽

Bao Shou Sun ◽

Min Xiao

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Process Parameters ◽

Rotational Speed ◽

Rolling Force ◽

Element Model ◽

Ring Rolling ◽

Force Analysis ◽

Closed Ring ◽

Feeding Speed

The rolling force will directly have influence on the size of high-neck flange and whether the rolled part will be shaped successfully. Finite element model of closed ring rolling high-neck flange was established, the effect of process parameters on rolling force and its reasons are analyzed. The results show that, the higher feeding speed is, the larger the amplification of rolling force will be, in addition, rolling force will be reduced slightly with the increase of rotational speed of driving roller, and the influence on the rolling force of compressing roller’s feeding speed is much larger than driving roller’s rotational speed.

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Simulation of Fracture Behavior in the Microstructure of Ceramic Tool Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.457-458.89 ◽

2012 ◽

Vol 457-458 ◽

pp. 89-92

Author(s):

Ting Ting Zhou ◽

Chuan Zhen Huang ◽

Han Lian Liu ◽

Jun Wang ◽

Bin Zou ◽

...

Keyword(s):

Finite Element ◽

Grain Boundary ◽

Fracture Resistance ◽

Fracture Behavior ◽

Single Phase ◽

Voronoi Tessellation ◽

Element Model ◽

Cohesive Element ◽

Ceramic Tool ◽

Tool Materials

In the paper, the Voronoi tessellation model is used to represent the microstructure of ceramic tool materials. And a finite element model based on cohesive element method has been developed to investigate the fracture behavior of the microstructure. The influences of mesh densities and cohesive parameters on the cracking patterns have been discussed. It is found that the enhancement of the grain boundary strength is beneficial for raising the fracture resistance of single-phase ceramic tool materials.

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