Four component three dimensional FEM analysis of flux concentration apparatus with four plates

1988 ◽  
Vol 24 (1) ◽  
pp. 126-129 ◽  
Author(s):  
T. Yoshimoto ◽  
S. Yamada ◽  
K. Bessho
Keyword(s):  
Three Dimensional ◽  
Fem Analysis ◽  
Flux Concentration

scholarly journals Experimental & FEM Analysis of Orthodontic Mini-Implant Design on Primary Stability

2021 ◽  
Vol 11 (12) ◽  
pp. 5461
Author(s):  
Elmedin Mešić ◽  
Enis Muratović ◽  
Lejla Redžepagić-Vražalica ◽  
Nedim Pervan ◽  
Adis J. Muminović ◽  
...  
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Primary Stability ◽  
Fem Analysis ◽  
Implant Design ◽  
Special Focus ◽  
Engineering System ◽  
Mini Implants ◽  
Pull Out ◽  
Computer Aided

The main objective of this research is to establish a connection between orthodontic mini-implant design, pull-out force and primary stability by comparing two commercial mini-implants or temporary anchorage devices, Tomas®-pin and Perfect Anchor. Mini-implant geometric analysis and quantification of bone characteristics are performed, whereupon experimental in vitro pull-out test is conducted. With the use of the CATIA (Computer Aided Three-dimensional Interactive Application) CAD (Computer Aided Design)/CAM (Computer Aided Manufacturing)/CAE (Computer Aided Engineering) system, 3D (Three-dimensional) geometric models of mini-implants and bone segments are created. Afterwards, those same models are imported into Abaqus software, where finite element models are generated with a special focus on material properties, boundary conditions and interactions. FEM (Finite Element Method) analysis is used to simulate the pull-out test. Then, the results of the structural analysis are compared with the experimental results. The FEM analysis results contain information about maximum stresses on implant–bone system caused due to the pull-out force. It is determined that the core diameter of a screw thread and conicity are the main factors of the mini-implant design that have a direct impact on primary stability. Additionally, stresses generated on the Tomas®-pin model are lower than stresses on Perfect Anchor, even though Tomas®-pin endures greater pull-out forces, the implant system with implemented Tomas®-pin still represents a more stressed system due to the uniform distribution of stresses with bigger values.

Three Dimensional Numerical Analyses of Bridge Piled-Raft Foundation under Riverbed Erosion

2012 ◽  
Vol 178-181 ◽  
pp. 2373-2377 ◽  
Author(s):  
Wen Tsung Liu ◽  
Yi Yi Li
Keyword(s):  
Bearing Capacity ◽  
Three Dimensional ◽  
Fem Analysis ◽  
Bridge Piers ◽  
Piled Raft Foundation ◽  
River Erosion ◽  
Dimensional Finite Element ◽  
The Face ◽  
Three Dimensional Finite Element

From the 921 earthquake to the major typhoons, including the Morakot typhoon, they damaged original landscape of rivers in Taiwan. In recent years, it alleged that abutment bridge exposed to the most serious security problems. Because of bridge piers in addition to the face of long-term river erosion, the flood on the pier will produce localized erosion near the bridge. The pier will be due to inadequate bearing capacity, resulting in subsidence, displacement, bridge version accompanied by tilting and even caving. The river erosion of soil around the piers deposits and production of contraction will often reduce the bearing capacity. Therefore, how to accurately estimate the scour depth, calculate piers to withstand water impact and analyses its stability for preventing injuries in the first place is the current pressing issues. In this study, three-dimensional finite element method (FEM) analysis program Plaxis 3D foundation is used. Polaris second bridge is selected for analysis. Based on local scouring of the model and various numerical variable conditions, the parameter of bridge pier is studied.

scholarly journals FEM analysis of a new miniplate: stress distribution on the plate, screws and the bone

2012 ◽  
Vol 06 (01) ◽  
pp. 009-015 ◽  
Author(s):  
Didem Nalbantgil ◽  
Murat Tozlu ◽  
Fulya Ozdemir ◽  
Mehmet Oguz Oztoprak ◽  
Tulin Arun
Keyword(s):  
Finite Element ◽  
Cortical Bone ◽  
Three Dimensional ◽  
Fem Analysis ◽  
Force Distribution ◽  
Bone Surface ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

ABSTRACTObjectives: Non-homogeneous force distribution along the miniplates and the screws is an unsolved question for skeletal anchorage in orthodontics. To overcome this issue, a miniplate structure was designed featuring spikes placed on the surface facing the cortical bone. The aim of this study was to examine and compare the force distribution of the newly designed plate-screw systems with the conventional one.Methods: A model of bone surface with 1.5 mm cortical thickness, along with the two newly designed miniplates and a standard miniplate-screw were simulated on the three-dimensional model. 200 g experimental force was applied to the tip of the miniplates and the consequential effects on the screws and cortical bone was evaluated using three-dimensional finite element method.Results: As a result of this finite element study, remarkably lower stresses were observed on the screws and the cortical bone around the screws with the newly designed miniplate when compared with the conventional one.Conclusion: The newly designed miniplate that has spikes was found effective in reducing the stress on and around the screws and the force was distributed more equivalently. (Eur J Dent 2012;6:9-15)

scholarly journals Experimental and FEM Analysis of Void Closure in the Hot Cogging Process of Tool Steel

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 538 ◽  
Author(s):  
Marcin Kukuryk
Keyword(s):  
Hydrostatic Stress ◽  
Effective Strain ◽  
Three Dimensional ◽  
Stress Triaxiality ◽  
Fem Analysis ◽  
Experimental Tests ◽  
Reduction Ratio ◽  
Compression Process ◽  
Void Closure ◽  
Axial Defects

In the present study, a new complex methodology for the analysis the closure of voids and a new forging system were developed and tested. The efficiency of the forging parameters and the effective geometric shapes of anvils to improve void closure were determined. A new cogging process provided a complete closure of an ingot’s axial defects, as confirmed by experimental tests. The evolution behavior of these defects with different sizes was investigated during the hot cogging process by means of the professional plastic forming software Deform-3D. A comprehensive procedure was developed using the finite-element method (FEM) for the three-dimensional cogging process and laboratory experimentation to predict the degree of void closure. The hot multi-pass cogging process was used to eliminate void defects in the forgings so as to obtain sound products. In the compression process, the effects of the reduction ratio and forging ratio, the void size, and the types of anvil were discussed to obtain the effective elimination of a void. For the purpose of the assessment of the effectiveness of the void closure process, the following indices were introduced: the relative void volume evolution ratio, the relative void diameter ratio, and the internal void closure evaluation index. Moreover, the void closure process was assessed on the basis of stress triaxiality, hydrostatic stress, forging ratio, value of local effective strain around the void, and critical reduction ratio. The results of this research were complemented by experiments predicting the formation of fractures in the regions near the void and in the volume of the forging in the course of the cogging process. The comparison between the predicted and the experimental results showed a good agreement.

Fabrication of a piezoelectrically driven micropositioning 3-DOF stage with elastic body using a multi-material 3D printer

2020 ◽  
Vol 26 (9) ◽  
pp. 1579-1591
Author(s):  
Sang-Woo Baek ◽  
Nahm-Gyoo Cho ◽  
Dong-Hyeok Lee
Keyword(s):  
Elastic Body ◽  
Degrees Of Freedom ◽  
Three Dimensional ◽  
Fem Analysis ◽  
Experimental Results ◽  
Analysis Model ◽  
Content Type ◽  
Vision Measurement ◽  
Conventional Material ◽  
Single Material

Purpose This paper aims to propose a method for manufacturing multi-material monolithic structures with flexible materials to construct the elastic body by using a dual-nozzle three-dimensional printer to develop a piezoelectric (PZT)-driven micropositioning stage with three degrees of freedom (3-DOF) and flexure hinges. Design/methodology/approach Polylactic acid (PLA) and nylon were used for the lever structure’s frame and flexure hinge, respectively. Additionally, the stage consisted of three PZT actuators for fine movement in the nanometer scale in 3-DOF (x, y and θ-directions). For the design of the stage, the kinematic analysis model and the finite element method (FEM) analysis was undertaken for comparing between PLA with nylon (multi-material), PLA (single material) and aluminum (conventional-material). In addition, two verification experiments were implemented for the fabricated prototype stage. First, to evaluate various assessments (lever ratio, hysteresis, coupling error and resolution), a measurement is carried out using the three capacitive sensors. Then, a two-camera-vision measurement experiment was performed to verify the displacement and lever ratio over the full-scale working range of the fabricated positioning stage, and the results from the experimentation and the FEM analysis were compared. Findings The authors confirmed enhancements in the properties of the lever structure frame, which requires stiffness and of the hinge, which requires flexibility for elastic deformation. Comparing FEM analysis and experimental results, although the performance as shown by experimental results was lower: the maximum difference being 3.4% within the end-point working range; this difference was sufficient to be a plausible alternative for the aluminum-based stage. Originality/value Multi-material monolithic-structure fabrication has an effective advantage in improving the performance of the stage, by using a combination of materials capable of reinforcing the desired characteristics in the necessary parts. It was verified that the fabricated stage can substitute the aluminum-based stage and can achieve a higher performance than single-material stages. Thus, precise-positioning stages can be manufactured in many kinds of structures with various properties and contribute to weight reduction and low costs for application equipment.

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