Fracture Behavior of the Hot Rolled Strip’s Surface Scale Layer from Different Impacts Angles

2022 ◽  
Vol 905 ◽  
pp. 67-72
Author(s):  
Shang Wang ◽  
Rui Can Hao ◽  
Hua Gang Liu ◽  
Xiao Chen Wang ◽  
Quan Yang
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Element Model ◽  
Impact Angle ◽  
Rolled Strip ◽  
Shot Blasting ◽  
Cracking Behavior ◽  
Scale Layer ◽  
Hot Rolled ◽  
The Impact

In order to improve the energy efficiency of shot blasting impact descaling, a three-dimensional finite element impact descaling model was established. Based on the finite element model, the cracking behavior of the scale layer on hot rolled strip from different impacts angles was simulated. The results of finite element calculation and theoretical analysis show that: (1)Under the premise of constant velocity, the descaling area increases with the increase of impact angle, but the increasing rate tends to be moderate. (2)The depth of the impact tunnel and the residual compressive stress surface (-200 MPa) increase as the impact angle goes bigger. The ideal range of impact angle for shot blasting descaling should be 60°-75°.

scholarly journals The Distributed Lambda (λ) Model (DLM): A 3-D, Finite-Element Muscle Model Based on Feldman's λ Model; Assessment of Orofacial Gestures

2013 ◽  
Vol 56 (6) ◽  
pp. 1909-1923 ◽  
Author(s):  
Mohammad Ali Nazari ◽  
Pascal Perrier ◽  
Yohan Payan
Keyword(s):  
Finite Element ◽  
Isometric Force ◽  
Three Dimensional ◽  
Element Model ◽  
Muscle Model ◽  
Type Model ◽  
Model Assessment ◽  
Model Based ◽  
Muscle Tissues ◽  
The Impact

Purpose The authors aimed to design a distributed lambda model (DLM), which is well adapted to implement three-dimensional (3-D), finite-element descriptions of muscles. Method A muscle element model was designed. Its stress–strain relationships included the active force–length characteristics of the λ model along the muscle fibers, together with the passive properties of muscle tissues in the 3-D space. The muscle element was first assessed using simple geometrical representations of muscles in the form of rectangular bars. It was then included in a 3-D face model, and its impact on lip protrusion was compared with the impact of a Hill-type muscle model. Results The force–length characteristic associated with the muscle elements matched well with the invariant characteristics of the λ model. The impact of the passive properties was assessed. Isometric force variation and isotonic displacements were modeled. The comparison with a Hill-type model revealed strong similarities in terms of global stress and strain. Conclusion The DLM accounted for the characteristics of the λ model. Biomechanically, no clear differences were found between the DLM and a Hill-type model. Accurate evaluations of the λ model, based on the comparison between data and simulations, are now possible with 3-D biomechanical descriptions of the speech articulators because of the DLM.

Optimization of the Engine Hood to Reduce the Head Injury during the Vehicle-Human Collision

2012 ◽  
Vol 192 ◽  
pp. 29-36
Author(s):  
Yu Xin Wang ◽  
Qing Chun Wang ◽  
Jian Rong Fu ◽  
Hong Hai Qiao
Keyword(s):  
Finite Element ◽  
Head Injury ◽  
Optimization Design ◽  
Three Dimensional ◽  
Element Model ◽  
Head Model ◽  
Modeling Software ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element ◽  
The Impact

Effect of hard point of the engine hood on the head injury during the vehicle-human collision was studied to improve the design of engine hood. Firstly, the current common model of the engine hood was established with three-dimensional finite element modeling software, and 20 areas were divided, also a standard head finite element model was imported, secondly, each area of the engine hood was clashed by the standard head model, then the impact on the head injure was analyzed and the hard point of the hood area was achieved, thirdly, the optimization of the inside and outside panel materials and the plate structure were carried out to reduce the head damage. The simulation results show that the engine hood after optimization gave less damage to the head, which means the research carried out here is of a good reference to the engine hood optimization design for human protection

Simulation and Test for the Lightning Damage of the Glass Fiber Composites

2014 ◽  
Vol 1003 ◽  
pp. 78-84
Author(s):  
Xiao Ning Chen ◽  
Jin Long Zhao ◽  
Yun Sheng Zhang ◽  
Bin Zhang
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Element Model ◽  
Damage Mechanism ◽  
Glass Fiber Composites ◽  
Dimensional Finite Element ◽  
Aircraft Composites ◽  
Three Dimensional Finite Element ◽  
The Impact ◽  
Composites Panel

Theoretical deducing, simulated lightning test and finite element simulation are used to research the mechanism and state of lightning damage of the aircraft composites sandwich panels. It provides the basis for the design of the aircraft lightning protection. The three-dimensional finite element model of the composites panel is constructed through the thermal electrical-mechanical multi-Physics coupling field. According to the structure and the role process, the lightning effect of the aircraft composites is analysed to study the damage mechanism and the possible state of the composites panel that is struck by lightning. The impact current generator is used to carry out the simulated lightning test to observe the lightning effect of the composites panel. By comparing the results of the test and the simulation, the effectiveness and the correctness of the simulation are verified.

scholarly journals Stope Stability Assessment and Effect of Horizontal to Vertical Stress Ratio on the Yielding and Relaxation Zones Around Underground Open Stopes Using Empirical and Finite Element Methods

2017 ◽  
Vol 62 (3) ◽  
pp. 653-669 ◽  
Author(s):  
Mohammadali Sepehri ◽  
Derek Apel ◽  
Wei Liu
Keyword(s):  
Finite Element ◽  
Numerical Methods ◽  
Stress Ratio ◽  
Three Dimensional ◽  
Element Model ◽  
Underground Mine ◽  
Graph Method ◽  
The Stability ◽  
Stability Graph ◽  
The Impact

AbstractPredicting the stability of open stopes can be a challenging task for underground mine engineers. For decades, the stability graph method has been used as the first step of open stope design around the world. However, there are some shortcomings with this method. For instance, the stability graph method does not account for the relaxation zones around the stopes. Another limitation of the stability graph is that this method cannot to be used to evaluate the stability of the stopes with high walls made of backfill materials. However, there are several analytical and numerical methods that can be used to overcome these limitations. In this study, both empirical and numerical methods have been used to assess the stability of an open stope located between mine levels N9225 and N9250 at Diavik diamond underground mine. It was shown that the numerical methods can be used as complementary methods along with other analytical and empirical methods to assess the stability of open stopes. A three dimensional elastoplastic finite element model was constructed using Abaqus software. In this paper a sensitivity analysis was performed to investigate the impact of the stress ratio “k” on the extent of the yielding and relaxation zones around the hangingwall and footwall of the understudy stope.

Crash simulation of fuselage section in the rebound process and the secondary-impact process

2020 ◽  
Vol 92 (8) ◽  
pp. 1245-1256
Author(s):  
Zibo Jin ◽  
Daochun Li ◽  
Jinwu Xiang
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Element Model ◽  
Structural Vibration ◽  
Dynamic Simulations ◽  
Content Type ◽  
Secondary Impact ◽  
Impact Process ◽  
Impact Surface ◽  
The Impact

Purpose This paper aims to investigate the rebound process and the secondary-impact process of the fuselage section that occurs in the actual crash events. Design/methodology/approach A full-scale three-dimensional finite element model of the fuselage section was developed to carry out the dynamic simulations. The rebound process was simulated by removing the impact surface at a certain point, while the secondary-impact process was simulated by striking the impact surface against the fuselage bottom after the first impact. Findings For the rebound process, the fuselage structure restores deformation due to the springback of the fuselage bottom, and it results in structural vibration of the fuselage section. For the secondary-impact process, the fuselage deformation is similar with that of the single impact process, indicating that the intermittent impact loading has little influence on the overall deformation of the fuselage section. The strut failure is the determining factor to the acceleration responses for both the rebound process and the secondary-impact process. Practical implications The rebound process and the secondary-impact process, which is difficult to study by experiments, was investigated by finite element simulations. The structure deformations and acceleration responses were obtained, and they can provide guidance for the crashworthy design of fuselage structures. Originality/value This research first investigated the rebound process and the secondary-impact process of the fuselage section. The absence of the ground load and the secondary-impact was simulated by controlling the impact surface, which is a new simulating method and has not been used in the previous research.

scholarly journals Biomechanics of Calcaneus Impacted by Talus: A Dynamic Finite Element Analysis

2021 ◽  
Author(s):  
Mengquan Huang ◽  
Bin Yu ◽  
Yubiao Li ◽  
Chunlai Liao ◽  
Jun Peng ◽  
...  
Keyword(s):  
Finite Element ◽  
Articular Surface ◽  
Three Dimensional ◽  
Peak Stress ◽  
Lateral Wall ◽  
Element Model ◽  
Calcaneal Fracture ◽  
Element Analysis ◽  
Average Maximum ◽  
The Impact

Abstract BackgroundThe biomechanics of calcaneus impacted by the talus are unclear. We aimed to evaluate the biomechanical effect of the talus impacting on the calcaneus at different falling speed, and analyze the factors affecting calcaneal fracture.Methods A finite element model including the talus, calcaneus and ligaments was built using a variety of three-dimensional reconstruction software. The method of explicit dynamics was used to analyze the process of the talus impacting the calcaneus. Stress values of the posterior, middle, and anterior subtalar articular surface(PSAS, ISAS, ASAS), the calcaneocubic articular surface(CAS), the bottom of the calcaneus(BC), the medial wall (MW)and lateral wall (LW) of the calcaneus were extracted. Stress quantity and distribution changes in various parts of the calcaneus changed with speed were analyzed.ResultsPosterior subtalar articular surface reached the peak stress first during the process of talus impacting the calcaneus. The stress was mainly concentrated on the PSAS, ASAS, MW and GA. Comparing with the speed of 5m/s, the average maximum stress increased in each region of the calcaneus were: PSAS 73.81%, ISAS 7.11%, ASAS 63.57%, GA 89.10%, LW 140.16%, CAS 140.58%, BC 137.67%, MW 135.99% at a speed of 10m/s. The regions where the stress were concentrated changed, and the magnitude and sequence of stress peaks of calcaneus changed with speed also during the impact.Conclusion The falling speed affected the value and distribution of stress of the calcaneus, which was the most important factor leading to a calcaneal fracture. The magnitude and sequence of stress peaks might be important factors in determining the beginning and direction of fracture lines.

A numerical investigation of the influence of yarn-level finite-element model on energy absorption by a flexible-fabric armour during ballistic impact

2008 ◽  
Vol 222 (4) ◽  
pp. 259-276 ◽  
Author(s):  
M Grujicic ◽  
G Arakere ◽  
T He ◽  
M Gogulapati ◽  
B A Cheeseman
Keyword(s):  
Finite Element ◽  
Boundary Conditions ◽  
Three Dimensional ◽  
Element Model ◽  
Far Field ◽  
Field Boundary ◽  
Fem Model ◽  
Energy Absorbing ◽  
The Impact ◽  
Textile Fabric

A series of transient non-linear dynamic finite-element method (FEM) analyses pertaining to the interaction of a single-ply plain-woven balanced square textile-fabric armour with a spherical steel projectile is carried out in order to compare the corresponding results obtained for two different yarn models: (a) a solid FEM model in which the warp and weft yarns are represented using first-order three-dimensional solid elements and (b) a membrane model in which the same yarns are represented using second-order membrane elements. The analyses are carried out under different yarn—yarn and projectile—fabric frictional conditions and under different far-field boundary conditions applied to the edges of the fabric. The results obtained showed that the two sets of analyses yield comparable predictions regarding the temporal evolution and the spatial distribution of the deformation and damage fields within the fabric, regarding the ability of the fabric to absorb the projectile's kinetic energy and regarding the relative contributions of the main energy absorbing mechanisms. The work also confirmed the roles yarn—yarn and projectile—fabric friction play in the impact process as well as the effect of the far-field boundary conditions applied to the edges of the fabric.

scholarly journals Transient dynamic finite element simulation for prediction of surface integrity induced by waterjet peening

2019 ◽  
Vol 234 (1) ◽  
pp. 105-119
Author(s):  
Rihem Amri ◽  
Adnen Laamouri ◽  
Sondes Manchoul ◽  
Raouf Fathallah
Keyword(s):  
Finite Element ◽  
Surface Properties ◽  
Three Dimensional ◽  
Element Model ◽  
Transient Dynamic ◽  
Dynamic Finite Element ◽  
Impact Theory ◽  
Experimental Surface ◽  
Dimensional Simulation ◽  
The Impact

This paper aims to develop and validate the transient dynamic finite element three-dimensional simulation of a waterjet peening process to predict surface properties (residual stresses, plastic strains, surface roughness, and superficial damage). The finite-element model considers an impingement of multisets of droplets, which strike the treated surface by impact pressures over the corresponding contact regions at high velocities. The impact pressures and their durations are modelled by using the liquid impact theory combined with an impact velocity law depending on the main parameters of the process. The behavior law of the material is an elastoviscoplastic law coupled to the Johnson–Cook damage criterion. The effectiveness of this simulation is discussed in two cases: (i) a linear mono-set of droplets and (ii) multisets of droplets using the experimental results of a waterjet-peened Al7075-T6 aluminum alloy. The predictive results of surface properties obtained by simulation with multi-sets of droplets appear more realistic than those obtained by simulation with a single set of droplets and more close to the experimental surface properties.

scholarly journals A Parameterized Ultrasound-Based Finite Element Analysis of the Mechanical Environment of Pregnancy

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Andrea R. Westervelt ◽  
Michael Fernandez ◽  
Michael House ◽  
Joy Vink ◽  
Chia-Ling Nhan-Chang ◽  
...  
Keyword(s):  
Finite Element ◽  
Preterm Birth ◽  
Structural Parameters ◽  
Three Dimensional ◽  
Element Model ◽  
Cervical Length ◽  
Childhood Mortality ◽  
Cervical Canal ◽  
Element Analysis ◽  
The Impact

Preterm birth is the leading cause of childhood mortality and can lead to health risks in survivors. The mechanical functions of the uterus, fetal membranes, and cervix have dynamic roles to protect the fetus during gestation. To understand their mechanical function and relation to preterm birth, we built a three-dimensional parameterized finite element model of pregnancy. This model is generated by an automated procedure that is informed by maternal ultrasound measurements. A baseline model at 25 weeks of gestation was characterized, and to visualize the impact of cervical structural parameters on tissue stretch, we evaluated the model sensitivity to (1) anterior uterocervical angle, (2) cervical length, (3) posterior cervical offset, and (4) cervical stiffness. We found that cervical tissue stretching is minimal when the cervical canal is aligned with the longitudinal uterine axis, and a softer cervix is more sensitive to changes in the geometric variables tested.

Numerical Modeling of Laminated Glass Units

2015 ◽  
Vol 769 ◽  
pp. 316-319
Author(s):  
Alena Zemanova ◽  
Jan Zeman ◽  
Michal Sejnoha
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Plate Theory ◽  
Impact Resistance ◽  
Three Dimensional ◽  
Element Model ◽  
Laminated Plates ◽  
Laminated Glass ◽  
Membrane Effects ◽  
The Impact

Laminated glass has been developed to improve the impact resistance of brittle glass sheets and to prevent injuries and collapse of glass members. The goal of this contribution is to briefly introduce a finite element model based on the refined plate theory by Mau that can describe the response of laminated glass plates without the need for fully resolved three-dimensional simulations. Each layer is considered to behave according to the Reissner-Mindlin kinematics, complemented with membrane effects and the von Karman assumptions. The compatibility of independent layers is enforced by nodal Lagrange multipliers. Predictions of the finite element model, obtained with a MATLAB-based program LaPla (Laminated Plates) developed by the authors, are compared with simplified monolithic and layered limits and a semi-analytical solution.

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