Mechanism of Cross Bow in Single-Roll Transmission Temper Mill

2010 ◽  
Vol 145 ◽  
pp. 216-222 ◽  
Author(s):  
Jie Tao Dai ◽  
Qing Dong Zhang
Keyword(s):  
Finite Element ◽  
Analytical Calculation ◽  
Element Model ◽  
Calculation Model ◽  
Vertical Extension ◽  
Width Direction ◽  
Symplectic Elasticity ◽  
The Cross ◽  
The Relationship ◽  
Roll Drive

In a 1220mm temper mill, the cross bow was serious, which seriously affected the unit’s output and efficiency. In order to solve this problem, the mechanism of cross bow is studied in rolling of single-roll transmission temper mill. First, established the FEM of the single-roll drive temper mill rolling, analyzed the distribution factors of vertical extension in thickness. Second, used the method of symplectic elasticity to establish the analytical calculation model to study the relationship between the cross bow with the uneven vertical extension, explained the mechanism of cross bow. Then, used ANSYS to establish finite element model which further analyzed the cross bow under different distribution of extension in width direction. On the basis of analyzed the mechanism, proposed measures to reduce the value of cross bow. These measures have been applied in production; the effect of application was obvious.

Finite Element Analysis of the ESTELA M1 Airplane Firewall (Representative Specimen)

2011 ◽  
Author(s):  
V. Ramirez-Elias ◽  
E. Ledesma-Orozco ◽  
H. Hernandez-Moreno
Keyword(s):  
Finite Element ◽  
Federal Aviation Administration ◽  
Element Model ◽  
Maximum Load ◽  
Load Factor ◽  
Representative Specimen ◽  
Maximum Displacement ◽  
Element Analysis ◽  
Element Simulation ◽  
The Relationship

This paper shows the finite element simulation of a representative specimen from the firewall section in the AEROMARMI ESTELA M1 aircraft. This specimen is manufactured in glass and carbon / epoxy laminates. The specimen is subjected to a load which direction and magnitude are determined by a previous dynamic loads study [10], taking into account the maximum load factor allowed by the FAA (Federal Aviation Administration) for utilitarian aircrafts [11]. A representative specimen is manufactured with the same features of the firewall. Meanwhile a fix is built in order to introduce the load directions on the representative specimen. The relationship between load and displacement is plotted for this representative specimen, whence the maximum displacement at the specific load is obtained, afterwards it is compared with the finite element model, which is modified in its laminate thicknesses in order to decrease the deviation error; subsequently this features could be applied to perform the whole firewall analysis in a future model [10].

scholarly journals Derivation of a finite-element model of lingual deformation during swallowing from the mechanics of mesoscale myofiber tracts obtained by MRI

2010 ◽  
Vol 109 (5) ◽  
pp. 1500-1514 ◽  
Author(s):  
Srboljub M. Mijailovich ◽  
Boban Stojanovic ◽  
Milos Kojic ◽  
Alvin Liang ◽  
Van J. Wedeen ◽  
...  
Keyword(s):  
Finite Element ◽  
Connective Tissue ◽  
Diffusion Tensor ◽  
Element Model ◽  
Out Of Plane ◽  
Posterior Direction ◽  
Elastic Constraints ◽  
The Relationship ◽  
Passive Muscle ◽  
Anterior Posterior

To demonstrate the relationship between lingual myoarchitecture and mechanics during swallowing, we performed a finite-element (FE) simulation of lingual deformation employing mesh aligned with the vector coordinates of myofiber tracts obtained by diffusion tensor imaging with tractography in humans. Material properties of individual elements were depicted in terms of Hill's three-component phenomenological model, assuming that the FE mesh was composed of anisotropic muscle and isotropic connective tissue. Moreover, the mechanical model accounted for elastic constraints by passive and active elements from the superior and inferior directions and the effect of out-of-plane muscles and connective tissue. Passive bolus effects were negligible. Myofiber tract activation was simulated over 500 ms in 1-ms steps following lingual tip association with the hard palate and incorporated specifically the accommodative and propulsive phases of the swallow. Examining the displacement field, active and passive muscle stress, elemental stretch, and strain rate relative to changes of global shape, we demonstrate that lingual reconfiguration during these swallow phases is characterized by (in sequence) the following: 1) lingual tip elevation and shortening in the anterior-posterior direction; 2) inferior displacement related to hyoglossus contraction at its inferior-most position; and 3) dominant clockwise rotation related to regional contraction of the genioglossus and contraction of the hyoglossus following anterior displacement. These simulations demonstrate that lingual deformation during the indicated phases of swallowing requires temporally patterned activation of intrinsic and extrinsic muscles and delineate a method to ascertain the mechanics of normal and pathological swallowing.

scholarly journals Curvature reduces bending strains in the quokka femur

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3100 ◽  
Author(s):  
Kyle McCabe ◽  
Keith Henderson ◽  
Jess Pantinople ◽  
Hazel L. Richards ◽  
Nick Milne
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Linear Relationship ◽  
Strain Gradient ◽  
Stance Phase ◽  
Element Model ◽  
Knee Extensors ◽  
Bending Strain ◽  
Biarticular Muscles ◽  
The Relationship

This study explores how curvature in the quokka femur may help to reduce bending strain during locomotion. The quokka is a small wallaby, but the curvature of the femur and the muscles active during stance phase are similar to most quadrupedal mammals. Our hypothesis is that the action of hip extensor and ankle plantarflexor muscles during stance phase place cranial bending strains that act to reduce the caudal curvature of the femur. Knee extensors and biarticular muscles that span the femur longitudinally create caudal bending strains in the caudally curved (concave caudal side) bone. These opposing strains can balance each other and result in less strain on the bone. We test this idea by comparing the performance of a normally curved finite element model of the quokka femur to a digitally straightened version of the same bone. The normally curved model is indeed less strained than the straightened version. To further examine the relationship between curvature and the strains in the femoral models, we also tested an extra-curved and a reverse-curved version with the same loads. There appears to be a linear relationship between the curvature and the strains experienced by the models. These results demonstrate that longitudinal curvature in bones may be a manipulable mechanism whereby bone can induce a strain gradient to oppose strains induced by habitual loading.

Rotor optimization for the improvement of ultrasonic motor performance

2019 ◽  
Vol 233 (19-20) ◽  
pp. 7089-7100 ◽  
Author(s):  
Zhangfan Xu ◽  
Sisi Di ◽  
Song Pan ◽  
Lei Chen ◽  
Weiqing Huang
Keyword(s):  
Finite Element ◽  
Stress Distribution ◽  
Shell Structure ◽  
Motor Performance ◽  
Thin Shell ◽  
Element Model ◽  
Ultrasonic Motor ◽  
Comsol Multiphysics ◽  
New Approach ◽  
The Relationship

The rotor deformation of an ultrasonic motor is an important factor affecting its performance. However, little research focuses on the relationship between the rotor deformation and motor performance. This paper provides an approach to improve the ultrasonic motor's output properties by changing the rotor's size from the view of proper rotor deformation and better stress distribution on the interface. First, a thin shell structure is introduced to study the deformation of the rotor. A finite element model of the motor is built in COMSOL Multiphysics software for the contact analysis of the stress distribution. Then, the optimized ranges of parameters are determined by simulation. Frictional experiments are conducted to verify the feasibility of the rotor under the optimized size. Finally, the performance experiments of a stator corresponding to different sizes of rotor are carried out. The experimental results show that the speed, the power and the efficiency of the optimized rotor are all increase. These results prove the effectivity of the new approach to improving the performance of the ultrasonic motor.

Establishment Method of the Simplified Model for Research on the Crashworthiness of B-Pillar in Side Impact

2014 ◽  
Vol 635-637 ◽  
pp. 502-506 ◽  
Author(s):  
Wei Min Zhuang ◽  
Qin Hua Xu
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
High Accuracy ◽  
Side Impact ◽  
Simplified Model ◽  
Body Parts ◽  
Establishment Method ◽  
Short Time ◽  
The Relationship

In order to improve the efficiency of the calculation of the whole car side impact finite element model,simplified model often used in research of B-pillar in passenger car. It is critical to establish a high accuracy simplified model in a short time. The relationship between the energy absorption of body parts and the calculation accuracy of simplified model was analyzed,and the result can be used as a guide for the establishment of simplified model.

Influence of Cable Dampers on Cable-Stayed Bridges

2012 ◽  
Vol 256-259 ◽  
pp. 1474-1479
Author(s):  
Dong Liang ◽  
Hui Cai Shen ◽  
Yan Feng Li
Keyword(s):  
Finite Element ◽  
Element Model ◽  
Test Model ◽  
Cable Stayed Bridge ◽  
Modal Damping ◽  
Mode Method ◽  
Practical Model ◽  
The Relationship ◽  
Theoretical Results ◽  
Cable Stayed Bridges

Cable-stayed bridges have seen a wider application in recent years, with many having longer and longer spans. Modern cable-stayed bridges are using numerous cables to support the stiffing girders. Many cable dampers are installed to mitigate cable vibration. This paper focuses the attention on the effect of cable damper on the dynamic characteristics of the whole cable-stayed bridge, especially the modal damping. A practical model comprised of the cable, girder, and damper is developed to analyze the relationship between system modal damping and the performance of cable damper with complex mode method. A test model with cable, girder and damper was made to verify the theoretical results. A finite element model of a simplified cable-stayed bridge based on test model is adopted to assess the effects of cable dampers on the anti-seismic performance and wind-resistant behavior of the cable-stayed bridge. The results show that the cable dampers of cable-stayed bridge can increase the modal damping of the whole bridge.

Finite Element Simulation of Metal Structure for Container Stacker Based on Ansys

2011 ◽  
Vol 94-96 ◽  
pp. 2080-2083
Author(s):  
Zhi Jian Li ◽  
Jian Kun Zhang
Keyword(s):  
Boundary Condition ◽  
Finite Element ◽  
Finite Element Model ◽  
Metal Structure ◽  
Element Model ◽  
Calculation Model ◽  
Ansys Software ◽  
Element Simulation ◽  
Calculation Results ◽  
The Finite Element Model

The finite element model of metal structure of 45 tons container stacker is established and Ansys software is employed to calculate the stress of key parts. The skill of model processing of the complete machine and the boundary condition of calculation model is described. The calculation results are used to guide the design of the container stacker.

Residual Elastic Strains in Autofrettaged Tubes: Variational Analysis by the Eigenstrain Finite Element Method

2006 ◽  
Vol 74 (4) ◽  
pp. 717-722 ◽  
Author(s):  
Alexander M. Korsunsky ◽  
Gabriel M. Regino
Keyword(s):  
Residual Stress ◽  
Plastic Deformation ◽  
Finite Element ◽  
Elastic Limit ◽  
Element Model ◽  
Underlying Distribution ◽  
Residual Strains ◽  
The Relationship ◽  
Inelastic Strains ◽  
Elastic Strains

Autofrettage is a treatment process that uses plastic deformation to create a state of permanent residual stress within thick-walled tubes by pressurizing them beyond the elastic limit. The present paper presents a novel analytical approach to the interpretation of residual elastic strain measurements within slices extracted from autofrettaged tubes. The central postulate of the approach presented here is that the observed residual stress and residual elastic strains are secondary parameters, in the sense that they arise in response to the introduction of permanent inelastic strains (eigenstrains) by plastic deformation. The problem of determining the underlying distribution of eigenstrains is solved here by means of a variational procedure for optimal matching of the eigenstrain finite element model to the observed residual strains reported in the literature by Venter et al., 2000, J. Strain Anal., 35, p. 459. The eigenstrain distributions are found to be particularly simple, given by one-sided parabolas. The relationship between the measured residual strains within a thin slice to those in a complete tube is discussed.

scholarly journals Forming Analysis of Bulge Formed Joints Based on Adaptive Finite Element Method

Mechanika ◽  
2021 ◽  
Vol 27 (2) ◽  
pp. 175-181
Author(s):  
Jinjin ZHAI ◽  
Yuantao SUN ◽  
Qing ZHANG ◽  
Xianrong QIN
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Production Efficiency ◽  
Element Model ◽  
Large Error ◽  
Calculation Model ◽  
Adaptive Finite Element Method ◽  
Adaptive Finite Element ◽  
Forming Process ◽  
Element Method

Metal bulk forming is widely used because of its own advantages. In order to improve the production efficiency and reduce the cost, numerical simulation is often used to analyze the volume forming process. Because of the large deformation and non-linearity of the forming process, the finite element method (FEM) has the problem of element distortion, which will affect the accuracy and even lead to the failure of the analysis process. In this paper, an adaptive finite element method (AFEM) is proposed to solve this problem. Firstly, the finite element model is established, and grids are roughly divided. After the analysis, according to the error calculation model, the area with large error is determined by the standard deviation of nominal strain energy of nodes. Then, the grids are refined by dichotomy method, and the calculation is continued, repeating this step until the error meets the requirement. Finally, the numerical analysis of the forging process of the bulge formed joint is taken as an example to prove the accuracy of the proposed method.  

Sign in / Sign up

Export Citation Format

Share Document