scholarly journals Spatial Uncertainty Modeling for Surface Roughness of Additively Manufactured Microstructures via Image Segmentation

2019 ◽  
Vol 9 (6) ◽  
pp. 1093 ◽  
Author(s):  
Namjung Kim ◽  
Chen Yang ◽  
Howon Lee ◽  
Narayana Aluru
Keyword(s):  
Finite Element ◽  
Image Segmentation ◽  
Compressive Loading ◽  
Dimensional Accuracy ◽  
Element Model ◽  
Spatial Uncertainty ◽  
Von Mises Stress ◽  
Modeling Framework ◽  
Element Analysis ◽  
Manufacturing Method

Despite recent advances in additive manufacturing (AM) that shifts the paradigm of modern manufacturing by its fast, flexible, and affordable manufacturing method, the achievement of high-dimensional accuracy in AM to ensure product consistency and reliability is still an unmet challenge. This study suggests a general method to establish a mathematical spatial uncertainty model based on the measured geometry of AM microstructures. Spatial uncertainty is specified as the deviation between the planned and the actual AM geometries of a model structure, high-aspect-ratio struts. The detailed steps of quantifying spatial uncertainties in the AM geometry are as follows: (1) image segmentation to extract the sidewall profiles of AM geometry; (2) variability-based sampling; (3) Gaussian process modeling for spatial uncertainty. The modeled spatial uncertainty is superimposed in the CAD geometry and finite element analysis is performed to quantify its effect on the mechanical behavior of AM struts with different printing angles under compressive loading conditions. The results indicate that the stiffness of AM struts with spatial uncertainty is reduced to 70% of the stiffness of CAD geometry and the maximum von Mises stress under compressive loading is significantly increased by the spatial uncertainties. The proposed modeling framework enables the high fidelity of computer-based predictive tools by seamlessly incorporating spatial uncertainties from digital images of AM parts into a traditional finite element model. It can also be applied to parts produced by other manufacturing processes as well as other AM techniques.

An Improved Control Arm Design for a Commercial Vehicle

2021 ◽  
Author(s):  
Sinan Yıldırım ◽  
Ufuk Çoban ◽  
Mehmet Çevik
Keyword(s):  
Finite Element ◽  
Cost Effective ◽  
Element Model ◽  
Tensile Tests ◽  
The Body ◽  
Von Mises Stress ◽  
Driving Safety ◽  
Design Development ◽  
Element Analysis ◽  
Von Mises

Suspension linkages are one of the fundamental structural elements in each vehicle since they connect the wheel carriers i.e. axles to the body of the vehicle. Moreover, the characteristics of suspension linkages within a suspension system can directly affect driving safety, comfort and economics. Beyond these, all these design criteria are bounded to the package space of the vehicle. In last decades, suspension linkages have been focused on in terms of design development and cost reduction. In this study, a control arm of a diesel public bus was taken into account in order to get the most cost-effective design while improving the strength within specified boundary conditions. Due to the change of the supplier, the control arm of a rigid axle was redesigned to find an economical and more durable solution. The new design was analyzed first by the finite element analysis software Ansys and the finite element model of the control arm was validated by physical tensile tests. The outputs of the study demonstrate that the new design geometry reduces the maximum Von Mises stress 15% while being within the elastic region of the material in use and having found an economical solution in terms of supplier’s criteria.

Finite Element Analysis of the Thermal Field of Piston in an External Combustion Cam Engine

2011 ◽  
Vol 66-68 ◽  
pp. 1240-1244
Author(s):  
Sheng Yao Gao ◽  
De Shi Wang ◽  
Qi Zheng Zhou
Keyword(s):  
Finite Element ◽  
Temperature Field ◽  
Optimization Design ◽  
Structural Parameters ◽  
Element Model ◽  
Von Mises Stress ◽  
Strength Analysis ◽  
Element Analysis ◽  
Technical Improvement ◽  
External Combustion

As the most dominative component under stress in an external combustion cam engine, the working condition of piston is very rigor. Once new design type and technical improvement is applied, it is necessary to analysis its thermal load and take secure steps. And the finite element model on each conditions of thermal is calculated, which is used to estimate the temperature field and provide a theoretical basis for further structural strength analysis and optimization design. Choosing analysis results of the piston as reference and taking five structural parameters of the piston as design variables, two objective functions including piston mass and maximal Von Mises stress are respectively considered. The optimum design of the piston is executed and the results indicate that it is feasible to improve temperature field and strength of the piston. These results enrich and develop the research on structural analysis and optimization of spatial engine, which are of guiding significance for analyzing engine strength and related problem in theoretically.

scholarly journals Torsional Behaviour and Finite Element Analysis of the Hybrid Laminated Composite Shafts: Comparison of VARTM with Vacuum Bagging Manufacturing Method

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Mehmet Emin Taşdelen ◽  
Mehmet Halidun Keleştemur ◽  
Ercan Şevkat
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Glass Fibers ◽  
Laminated Composite ◽  
Experimental Tests ◽  
Element Model ◽  
Performance Criteria ◽  
Fiber Types ◽  
Element Analysis ◽  
Manufacturing Method

Braided sleeve composite shafts are produced and their torsional behavior is investigated. The braided sleeves are slid over an Al tube to create very strong and rigid tubular form shafts and they are in the form of 2/2 twill biaxial fiber fabric that has been woven into a continuous sleeve. Carbon and glass fibers braided sleeves are used for the fabrication of the composite shafts. VARTM (vacuum assisted resin transfer molding) and Vacuum Bagging are the two different types of manufacturing methods used in the study. Torsional behaviors of the shafts are investigated experimentally in terms of fabrication methods and various composite materials parameters such as fiber types, layer thickness, and ply angles. Comparing the two methods in terms of the torque forces and strain angles, the shafts producing entirely carbon fiber show the highest torque capacities; however, considering the cost and performance criteria, the hybrid shaft made up of carbon and glass fibers is the optimum solution for average demanded properties. Additionally, FE (finite element) model of the shafts was created and analyzed by using ANSYS workbench environment. Results of finite element analysis are compared with the values of twisting angle and torque obtained by experimental tests.

Finite Element Analysis of Gold Bonding under Different Loading Conditions

2014 ◽  
Vol 607 ◽  
pp. 713-716
Author(s):  
Wen Liang Tang ◽  
Chun Yue Huang ◽  
Tian Ming Li ◽  
Ying Liang ◽  
Guo Ji Xiong ◽  
...  
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Element Model ◽  
Simulation Software ◽  
Bonding Time ◽  
Von Mises Stress ◽  
Bonding Pressure ◽  
Element Analysis ◽  
Von Mises ◽  
Three Dimensional Finite Element

In this paper, ANSYS-LSDYNA simulation software is used to build the three-dimensional finite element model of the ball bond and to get the Von Mises stress. The change of stress about the bump is researched which base on the model in different bonding pressure, bonding power and bonding time. The result show that: The stress increase with bonding pressure increase within a certain bonding pressure range, and then the stress will maintain a table number, however, the stress will continue to increase when the bonding pressure reach a certain value; increasing the bonding power, the area of lager stress will grow; prolonging the bonding time, the stress of the pad will increase with time, but when time increase to a certain value, the stress of the pad will not increase over time.

Finite Element Analysis of Screw-Plate Systems for Fixation of Parasymphyseal Fractures of the Mandible

2007 ◽  
Vol 23 (1) ◽  
pp. 69-77 ◽  
Author(s):  
Scott T. Lovald ◽  
Tariq Khraishi ◽  
John Wood ◽  
Jon Wagner ◽  
Bret Baack ◽  
...  
Keyword(s):  
Finite Element ◽  
Element Model ◽  
Point Of View ◽  
Von Mises Stress ◽  
Element Analysis ◽  
Fracture Region ◽  
Modeling Practices ◽  
Orthotropic Properties ◽  
Von Mises ◽  
Early Healing

AbstractFinite Element Modeling was used to compare the efficacy of common screw-plate configurations used for fixation of parasymphyseal fractures of the mandible. Measures of Von Mises stress on the screw bone interface, as well as principal strain in the reduced fracture region, were used in this comparison. This study also explored differences between orthotropic and isotropic modeling practices and compared the effect of mastication forces on both the fractured and intact halves of the mandible. The results of this analysis showed no major differences between configurations from a mechanistic point of view. This suggests that the use of any of the studied screw-plate configurations will not increase chances for post-operative complications. Furthermore, little difference is seen between analyses with either orthotropic or isotropic material properties. The inclusion of orthotropic properties can thus be avoided in future studies with similar boundary and plating conditions. Mastication ipsilateral to the fracture increases Von Mises stress 2 to 4 times, and should be avoided during early healing periods. These recommendations only apply to patients whose fractures mimic the finite-element model.

Evaluation of Biomechanical Health Degree of Peri-Implant Bone Through Finite Element Analysis: A First Approach

2018 ◽  
Vol 10 (09) ◽  
pp. 1850097 ◽  
Author(s):  
Junxiong Lin ◽  
Ge Zhang ◽  
Zhenyu Jiang ◽  
Liqun Tang ◽  
Keqian Lian
Keyword(s):  
Finite Element ◽  
Stress State ◽  
Critical Role ◽  
Control Sample ◽  
Stress Shielding ◽  
Element Model ◽  
Von Mises Stress ◽  
Element Analysis ◽  
Computer Tomography Scan ◽  
Von Mises

The biomechanical health degree of peri-implant bone plays a critical role during the service of implants. This paper presents a preliminary exploration of the quantitative evaluation of the biomechanical health degree for the bone tissues around dental implant through finite element method. The finite element model of a part of mandible with three molars is constructed based on computer tomography scan image as a control sample, which is supposed to represent a healthy state. The model of treated mandible is made by replacing the middle tooth in the healthy model with a commercial implant. A regional average strain energy density (RASED) is proposed as a more accurate index to describe the stress state of peri-implant bone tissues, compared with the widely used maximum equivalent von Mises stress. The simulation shows that the stress state in peri-implant bone, i.e., the distribution and level of stress, is highly dependent on the modulus of implant material. Among the implants made of materials with various moduli, including Ti, stainless steel, zirconia, porous Ti, dentin material and polyether-ether-ketone (PEEK), the ones with medium modulus (15–40[Formula: see text]GPa) are found to achieve relatively healthy stress states. This study provides an effective tool to assess the risk of overloading or stress shielding in peri-implant bone tissues. It demonstrates a great potential in the optimization of design, production and usage of implants.

Finite Element Model of a Cell Incorporating Cell Membrane, Cytoskeletal Structure and Intracellular Fluid Pressure

2002 ◽  
Author(s):  
Vidyashankar Venkatesan ◽  
Nilay Mukherjee
Keyword(s):  
Finite Element ◽  
Compressive Loading ◽  
Fluid Pressure ◽  
Element Model ◽  
Structural Components ◽  
Element Analysis ◽  
In Situ Experiments ◽  
A Cell

Compressive loading is intrinsic to certain tissues in our body like articular cartilage and bone (1). In situ experiments in cartilage suggest that chondrocytes can undergo significant deformation due to compressive loading on the tissue (2). In situ and isolated cell experiments have concluded that cells are quite resilient to compressive loading, aspiration etc. and exhibit a moduli in the range of 0.6 to 2 kPa (3). However, few studies have attempted to understand the compressive behavior of cells in terms of its structural components. The structural components of a cell consist of a membrane and a dense network of at least three elements (actin, microtubules and intermediate filaments). Using finite element analysis techniques we wanted to explore the role of these structural components in determining the ability of the cell to withstand compression.

Coupled Thermal Analysis on Carbide Anvil of Cubic Press

2014 ◽  
Vol 852 ◽  
pp. 629-633
Author(s):  
Xian Jun Zhou ◽  
Zhong Wen Xu ◽  
Ren Quan Chen ◽  
Shao Ping Li
Keyword(s):  
Thermal Analysis ◽  
Finite Element ◽  
Shear Stress ◽  
Element Model ◽  
Heat Transfer Analysis ◽  
Von Mises Stress ◽  
Element Analysis ◽  
Material Defects ◽  
Indirect Coupling ◽  
Von Mises

Based on finite element analysis software ANSYS, the 3D contact finite element model of carbide anvil, steel ring and cushion block were built to make heat transfer analysis, and the temperature field distribution was obtained. The indirect coupling thermal analysis of carbide anvil, steel ring and cushion block were made regarding as a whole, the Von Mises stress nephogram of them and the shear stress nephogram of carbide anvil were displayed. The stress nephogram revealed that it was liable to fracture on the edge of top surface under high pressure status, and it was also proven that the main reason of fracture was the yield of internal material defects under the action of shear stress.

Finite Element Analysis for the Mega Columns for XRL West Kowloon Terminus

2013 ◽  
Vol 405-408 ◽  
pp. 1139-1143
Author(s):  
Wei Su ◽  
Ying Sun ◽  
Shi Qing Huang ◽  
Ren Huai Liu
Keyword(s):  
Finite Element ◽  
Stress Distribution ◽  
Parametric Design ◽  
Three Dimensional ◽  
Element Model ◽  
Von Mises Stress ◽  
Element Analysis ◽  
Dimensional Finite Element ◽  
Von Mises ◽  
Three Dimensional Finite Element

Using ANSYS parametric design language, a three-dimensional finite element model is developed to analyze the stress distribution and the strength of the mega columns for XRL West Kowloon Terminus. The detailed von Mises stress distribution in each column, vertical stiffener plates and the diaphragm plates is obtained. From the analysis, the phenomenon of stress concentration is obvious in both upper and lower diaphragm plates. The local value of von Mises stress in them is higher than the yield stress value, which must be avoided by more detailed local structural design.

scholarly journals Computerized Generation and Finite Element Stress Analysis of Endodontic Rotary Files

2021 ◽  
Vol 11 (10) ◽  
pp. 4329
Author(s):  
Victor Roda-Casanova ◽  
Álvaro Zubizarreta-Macho ◽  
Francisco Sanchez-Marin ◽  
Óscar Alonso Ezpeleta ◽  
Alberto Albaladejo Martínez ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Computer Aided Design ◽  
Element Model ◽  
Transverse Load ◽  
Von Mises Stress ◽  
Design Parameters ◽  
Element Analysis ◽  
Design Skills ◽  
Von Mises

Introduction: The finite element method has been extensively used to analyze the mechanical behavior of endodontic rotary files under bending and torsional conditions. This methodology requires elevated computer-aided design skills to reproduce the geometry of the endodontic file, and also mathematical knowledge to perform the finite element analysis. In this study, an automated procedure is proposed for the computerized generation and finite element analysis of endodontic rotary files under bending and torsional conditions. Methods: An endodontic rotary file with a 25mm total length, 0.25mm at the tip, 1.20mm at 16mm from the tip, 2mm pitch and squared cross section was generated using the proposed procedure and submitted for analysis under bending and torsional conditions by clamping the last 3mm of the endodontic rotary file and applying a transverse load of 0.1N and a torsional moment of 0.3N·cm. Results: The results of the finite element analyses showed a maximum von Mises stress of 398MPa resulting from the bending analysis and a maximum von Mises stress of 843MPa resulting from the torsional analysis, both of which are next to the encastre point. Conclusions: The automated procedure allows an accurate description of the geometry of the endodontic file to be obtained based on its design parameters as well as a finite element model of the endodontic file from the previously generated geometry.

Sign in / Sign up

Export Citation Format

Share Document