Modeling the Damage Progression in the Composite Structure Subjected to Static Contact Crush

2006 ◽  
Vol 324-325 ◽  
pp. 831-834
Author(s):  
Yun Peng Jiang ◽  
Wan Lin Guo
Keyword(s):  
Composite Structure ◽  
Damage Model ◽  
Damage Distribution ◽  
User Subroutine ◽  
Commercial Code ◽  
Static Contact ◽  
Laminate Theory ◽  
Damage Processes ◽  
Progressive Damage Model ◽  
Good Agreement

Based on the classic laminate theory, a progressive damage model has been incorporated into the composite structure analysis by using a commercial code, ABAQUS, via one of its user-defined subroutine, UGENS. The developed user subroutine can be applied to simulate fiber and matrix damage processes in the general composites structures. The responses of flat laminate subjected to static contact crush have been studied to verify the efficiency of the presented damage method. The predicted load-displacement relationships, damage distribution were obtained and compared with the corresponding experiments, and the results were found to be in good agreement.

Analysis for the Propagation of Edge Crack of Silicon Steel during Cold Rolling Process Based on GTN Damage Model

2012 ◽  
Vol 482-484 ◽  
pp. 487-492
Author(s):  
Yu Xi Yan ◽  
Quan Sun ◽  
Jian Jun Chen ◽  
Hong Liang Pan
Keyword(s):  
Cold Rolling ◽  
Edge Crack ◽  
Damage Model ◽  
Rolling Process ◽  
Silicon Steel ◽  
Damage Distribution ◽  
Initiation And Propagation ◽  
Gtn Damage Model ◽  
Edge Cracks ◽  
Good Agreement

Silicon steels tend to develop edge cracks during cold rolling, which need to be removed and cause rupture of the steel in the rolling mill. Hence, it is necessary to understand the formation of edge cracks. The damage distribution and the initiation and propagation of edge cracks occur around the notch tip during cold rolling process was investigated by using GTN damage model. The damage parameters f0, fcand fFare determined by tension experiments and SEM observation. The influence of various rolling parameters on damage distribution and crack length was simulated by using ABAQUS. The numerical results show that the GTN damage model is available to prediction the initiation and propagation of edge cracks during rolling process. Parametric study carried out in this present work reveals that the possible occurrence of edge cracks is higher at larger reduction, higher friction coefficient, smaller roll radius and stronger unit tension. The simulation and experimental results have a good agreement .

Assessment of the load carrying performance of composite cross joints

2019 ◽  
Vol 54 (11) ◽  
pp. 1431-1439
Author(s):  
Liyang Liu ◽  
Mengfei Cai ◽  
Xiaoliang Geng ◽  
Peiyan Wang ◽  
Zhufeng Yue
Keyword(s):  
Damage Model ◽  
Bending Moment ◽  
Comparative Assessment ◽  
Progressive Damage ◽  
Bending Tests ◽  
Air Inlet ◽  
Four Point Bending ◽  
Load Carrying ◽  
Progressive Damage Model ◽  
Good Agreement

Composite cross joints are common structures in an airframe. When this type of joint is used on an air inlet stiffened structure, it will undertake large bending moment, especially under overpressure of the engine. In this paper, two types of cross joints are tested experimentally and simulated to investigate the load bearing characteristics and make comparative remarks. Four-point bending tests are conducted and the load deflection curves are obtained; besides, the damage pattern of the joints is reported. Based on composite progressive damage model, the numerical simulations have a good agreement with experimental results, revealing the joint failure mechanism and fastener force feature of various joints. The comparative assessment of two types of joints is summarized.

scholarly journals Effects of Hole Perpendicularity Error on Mechanical Performance of Single-Lap Double-Bolt Composite Joints

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Xueshu Liu ◽  
Yuxing Yang ◽  
Yiqi Wang ◽  
Yongjie Bao ◽  
Hang Gao
Keyword(s):  
Failure Modes ◽  
Mechanical Performance ◽  
Damage Model ◽  
Composite Joints ◽  
Load Path ◽  
Direct Function ◽  
Tilting Angle ◽  
Static Tensile ◽  
Progressive Damage Model ◽  
Good Agreement

Static tensile experiments and numerical simulations were carried out to study effects of hole perpendicularity error on mechanical performance of single-lap double-bolt composite joints. Hole tilting angle, varying from 1 to 4 degrees, and hole tilting direction to account for anisotropic properties of composite material were investigated. Progressive damage model (PDM) based on Chang-Lessard type criterion with an extension by Olmedo was created, which involved seven failure modes and made material properties be a direct function of predefined field variables. The model was implemented in ABAQUS/Standard using a UMAT subroutine. Good agreement was found when comparing numerical simulation results with experimental outcomes. In addition, the results demonstrate that, with increasing of hole tilting angle, damage is prone to arise and the load path of the composite bolted joints alters with changing of hole tilting direction, which result in severe stress concentration around the edge of hole and joint failure in advance.

Progressive damage characteristics of screwed single-lap CFRPI-metal joint subjected to tensile loading at RT and 350°C

2021 ◽  
pp. 002199832098559
Author(s):  
Yun-Tao Zhu ◽  
Jun-Jiang Xiong ◽  
Chu-Yang Luo ◽  
Yi-Sen Du
Keyword(s):  
Damage Model ◽  
Tensile Loading ◽  
Tensile Tests ◽  
Displacement Curve ◽  
Progressive Damage ◽  
Damage Characteristics ◽  
Metal Joint ◽  
Static Tensile ◽  
Strength And Stiffness ◽  
Progressive Damage Model

This paper outlines progressive damage characteristics of screwed single-lap CFRPI-metal joints subjected to tensile loading at RT (room temperature) and 350°C. Quasi-static tensile tests were performed on screwed single-lap CCF300/AC721-30CrMnSiA joint at RT and 350°C, and the load versus displacement curve, strength and stiffness of joint were gauged and discussed. With due consideration of thermal-mechanical interaction and complex failure mechanism, a modified progressive damage model (PDM) based on the mixed failure criterion was devised to simulate progressive damage characteristics of screwed single-lap CCF300/AC721-30CrMnSiA joint, and simulations correlate well with experiments. By using the PDM, the effects of geometry dimensions on mechanical characteristics of screwed single-lap CCF300/AC721-30CrMnSiA joint were analyzed and discussed.

A progressive damage model for three-dimensional woven composites under ballistic impact loading

2019 ◽  
Vol 1 (1) ◽  
pp. 015028
Author(s):  
Yongqi Yang ◽  
Li Zhang ◽  
Licheng Guo ◽  
Suyang Zhong ◽  
Jiuzhou Zhao ◽  
...  
Keyword(s):  
Impact Loading ◽  
Damage Model ◽  
Three Dimensional ◽  
Ballistic Impact ◽  
Woven Composites ◽  
Progressive Damage ◽  
Progressive Damage Model

scholarly journals A bi-dissipative damage model for concrete

2015 ◽  
Vol 8 (1) ◽  
pp. 49-65
Author(s):  
J. J. C. Pituba ◽  
W. M. Pereira Júnior
Keyword(s):  
Reinforced Concrete ◽  
Structural Engineering ◽  
Damage Mechanics ◽  
Damage Model ◽  
Continuum Damage Mechanics ◽  
Concrete Material ◽  
Framed Structures ◽  
Energy Equivalence ◽  
Proposed Model ◽  
Damage Processes

This work deals with an improvement of an anisotropic damage model in order to analyze reinforced concrete structures submitted to reversal loading. The original constitutive model is based on the fundamental hypothesis of energy equivalence between real and continuous media following the concepts of the Continuum Damage Mechanics. The concrete is assumed as an initial elastic isotropic medium presenting anisotropy, permanent strains and bimodularity induced by damage evolution. In order to take into account the bimodularity, two damage tensors governing the rigidity in tension or compression regimes are introduced. However, the original model is not capable to simulate the influence of the previous damage processes in compression regimes. In order to avoid this problem, some conditions are introduced to simulate the damage unilateral effect. It has noted that the damage model is agreement with to micromechanical theory conditions when dealing to unilateral effect in concrete material. Finally, the proposed model is applied in the analyses of reinforced concrete framed structures submitted to reversal loading. These numerical applications show the good performance of the model and its potentialities to simulate practical problems in structural engineering.

scholarly journals A progressive damage model of composite laminates under low-velocity impact

2021 ◽  
Vol 39 (1) ◽  
pp. 37-45
Author(s):  
Junjie Zhou ◽  
Shengnan Wang
Keyword(s):  
Composite Laminates ◽  
Impact Force ◽  
Damage Model ◽  
Low Velocity Impact ◽  
Progressive Damage ◽  
Low Velocity ◽  
Damage Development ◽  
Velocity Impact ◽  
Progressive Damage Model ◽  
Matrix Damage

In this paper, a progressive damage model for studying the dynamic mechanical response and damage development of composite laminates under low-velocity impact was established. The model applied the Hashin and Hou failure criteria to predict the initiation of intra-laminar damage (fiber and matrix damage); a linear degradation scheme combined with the equivalent displacement method was adopted to simulate the damage development; a cohesive zone model with the bilinear traction-separation relationship was used to predict delamination. A user material subroutine VUMAT was coded, and the simulation analysis of carbon fiber reinforcement composite laminates subjected to 25 J impact was performed via commercial software ABAQUS. The predicted impact force-time curve, impact force-displacement curve, and damage distribution contours among the layers were in a good agreement with the experimental, which verified the proposed model. According to the simulation results, the fiber damage and matrix damage were analyzed, and the expansion of delamination was discussed.

scholarly journals A Strain Rate Dependent Progressive Damage Model for Carbon Fiber Woven Composites under Low Velocity Impact

2021 ◽  
Vol 2101 (1) ◽  
pp. 012073
Author(s):  
Xueyao Hu ◽  
Jiaojiao Tang ◽  
Wei Xiao ◽  
Kepeng Qu
Keyword(s):  
Strain Rate ◽  
Damage Model ◽  
Low Velocity Impact ◽  
Woven Composites ◽  
Progressive Damage ◽  
Low Velocity ◽  
Velocity Impact ◽  
Rate Dependent ◽  
Plane Direction ◽  
Progressive Damage Model

Abstract A progressive damage model was presented for carbon fiber woven composites under low velocity impact, considering the strain rate sensitivity of both mechanical properties and failure mechanisms. In this model, strain rate dependency of elastic modulus and nominal strength along in-plane direction are considered. Based on the Weibull distribution, stiffness progressive degradation is conducted by introducing strain rate dependent damage variables for distinct damage modes. With the model implemented in ABAQUS/Explicit via user-defined material subroutine (VUMAT), the mechanical behavior and possible damage modes of composites along in-plane direction can be determined. Furthermore, a bilinear traction separation model and a quadratic stress criterion are applied to predict the initiation and evolution of interlaminar delamination. Comparisons are made between the experimental results and numerical simulations. It is shown that the mechanical response and damage characteristics under low velocity impact, such as contact force history and delamination, are more consistent with the experimental results when taken the strain rate effect into consideration.

Numerical Simulation of the Unsteady Flow Patterns in a Small Squirrel-Cage Fan

2006 ◽  
Author(s):  
Sandra Velarde-Sua´rez ◽  
Rafael Ballesteros-Tajadura ◽  
Jose´ Gonza´lez-Pe´rez ◽  
Bruno Pereiras-Garci´a
Keyword(s):  
Numerical Simulation ◽  
Air Conditioning ◽  
Flow Distribution ◽  
Geometrical Model ◽  
Squirrel Cage ◽  
Automotive Air Conditioning ◽  
Commercial Code ◽  
Performance Curves ◽  
Flow Features ◽  
Good Agreement

In this work, a numerical simulation on the main flow features in a squirrel-cage fan, used in automotive air conditioning units, has been carried out. A 3D unsteady model has been developed for the entire machine. The flow in this geometrical model has been solved using the commercial code FLUENT®. Some of the analyzed features are the performance curves, the flow distribution over the different aspiration sections, the pressure and velocity distributions in selected surfaces, and the forces on the blades and on the whole impeller. The numerical results have been compared with the available experimental data, showing a reasonable good agreement.

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