iMechanica - Abaqus 6.12
https://imechanica.org/taxonomy/term/8400
enHow to obtain the Force-Indentation depth curve of nanoindentation FEA?
https://imechanica.org/node/19607
<div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/11032">Nanoinentation</a></div><div class="field-item odd"><a href="/taxonomy/term/8400">Abaqus 6.12</a></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p id="yui_3_14_1_1_1457772578632_2341">I did FEA of nanoindentation with using Abaqus and considered displacement of reference point (RP) on the indenter as a punching tool. Moreover, Abaqus/Explicit method was applied for solving problems.</p>
<p>But I do not know how to plot Force-Indention depth curve via FEA with using Abaqus.</p>
<p>Any suggestions would be greatly appreciated.</p>
<p>Amin</p>
<p><em><br /></em></p>
</div></div></div>Sat, 12 Mar 2016 08:52:24 +0000Amin Khajeh19607 at https://imechanica.orghttps://imechanica.org/node/19607#commentshttps://imechanica.org/crss/node/19607Abaqus DISP Subroutine
https://imechanica.org/node/18838
<div class="field field-name-taxonomy-vocabulary-6 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/75">mechanician</a></div></div></div><div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/8400">Abaqus 6.12</a></div><div class="field-item odd"><a href="/taxonomy/term/7392">Abaqus/Fortran</a></div><div class="field-item even"><a href="/taxonomy/term/10738">DISP</a></div><div class="field-item odd"><a href="/taxonomy/term/9291">abaqus subroutine</a></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><span>Hi everyone!! </span></p>
<p><span>I am a student studying in Hamburg University of Technology. I am currently doing my thesis and want some help in finishing it. I am finding it a bit difficult to do subroutine in Fortran as I am new to it. I have tried learning from Abaqus Documentation but I didn't get answer to my needs. </span></p>
<p><span>I already have a text file that contains Nodes, X,Y,Z coordinates and the displacement values to be assigned. </span><br /><span>For Example: Nodes X_coord Y_coord Z_coord U </span><br /><span> 1 0.23 1 .94 2.36+i.45 </span><br /><span> 62 .... ... .... .... </span><br /><span> ... </span><br /><span> 538 .... .... .... .... </span></p>
<p><span>It a basically a 304 x 5 matrix. I just need to assign the values of the displacements to these nodes using a subroutine. </span></p>
<p><span> SUBROUTINE DISP(U,KSTEP,KINC,TIME,NODE,NOEL,JDOF,COORDS) </span><br /><span>C </span><br /><span> INCLUDE 'ABA_PARAM.INC' </span><br /><span>C </span><br /><span> DIMENSION U(3),TIME(2),COORDS(3) </span><br /><span>C </span><br /><span> REAL,DIMENSION(304,5)::A </span><br /><span> A = OPEN(UNIT = 1, FILE ="Pressure_SAVAN_100Hz.txt", FORM = "FORMATTED", STATUS = "OLD", ACTION = "READ") </span><br /><span> </span><br /><span> DO I = 1, 304 </span><br /><span> IF (NODE.EQ.A(I,1)) THEN </span><br /><span> U(1) = A(I,5) </span><br /><span> ENDIF </span><br /><span> ENDDO </span><br /><span> </span><br /><span>RETURN </span><br /><span>END </span><br /><span>Please do notify me where I have gone wrong! Your help is much appreciated </span></p>
<p><span>Regards </span><br /><span>Savan</span></p>
</div></div></div>Sat, 12 Sep 2015 09:04:58 +0000SavanRGowda18838 at https://imechanica.orghttps://imechanica.org/node/18838#commentshttps://imechanica.org/crss/node/18838Simpleware case study: 3D FE Model of the Diabetic Neuropathic Foot
https://imechanica.org/node/18771
<div class="field field-name-taxonomy-vocabulary-6 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/76">research</a></div></div></div><div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/973">software</a></div><div class="field-item odd"><a href="/taxonomy/term/19">biomechanics</a></div><div class="field-item even"><a href="/taxonomy/term/6340"># Finite Element modeling</a></div><div class="field-item odd"><a href="/taxonomy/term/8400">Abaqus 6.12</a></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><img src="http://www.simpleware.com/img/casestudies/diabeticfoot_intro.png" alt="" width="410" height="185" /></p>
<p>Diabetic foot represents a complication of diabetes that can lead to foot ulcers and other serious conditions. 3D Finite Element (FE) analysis enables dynamic characterisation of different loads within the foot.</p>
<p>This study developed a subject-specific 3D FE model of a diabetic neuropathic and a healthy subject’s foot from MRI data. Experimental analysis of the biomechanics of the foot was combined with FE simulations of foot models generated in Simpleware software.</p>
<p>Subject-specific kinematics and kinetics data acquired during gait analysis were used in the simulations. The results obtained from the experimental and simulated studies can help researchers to better understand the aetiology of the diabetic foot.</p>
<p>(Thanks to: University of Padova (Departments of Information Engineering & Clinical Medicine and Metabolic Disease): A. Guiotto • Z. Sawacha • A. Scarton • G. Guarneri • A. Avogaro • C. Cobelli)</p>
<p><a href="http://simpleware.com/industries/medical-and-dental/orthopaedics/case-study-fe-model-of-the-diabetic-neuropathic-foot.html">Read more</a></p>
</div></div></div>Thu, 27 Aug 2015 13:19:52 +0000Simpleware18771 at https://imechanica.orghttps://imechanica.org/node/18771#commentshttps://imechanica.org/crss/node/18771Nonlinear structural analysis on ABAQUS
https://imechanica.org/node/18054
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Dear iMechanica users,</p>
<p>I am working on a metallic foam model, and due to its nature of geometry and physical properties, I considered geometrical and physical nonlinearities. What is the significance of NLGEOM = ON and NLGEOM = OFF besides, it includes or excludes the geomterical nonlinearity in ABAQUS? I want to know the basic change that has been incorporated when I switch the NLGEOM between ON and OFF. Also, a theoretical explanation on how this change is caried out. </p>
</div></div></div><div class="field field-name-taxonomy-forums field-type-taxonomy-term-reference field-label-above"><div class="field-label">Forums: </div><div class="field-items"><div class="field-item even"><a href="/forum/109">Ask iMechanica</a></div></div></div><div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-above"><div class="field-label">Free Tags: </div><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/2966">NLGEOM</a></div><div class="field-item odd"><a href="/taxonomy/term/8400">Abaqus 6.12</a></div><div class="field-item even"><a href="/taxonomy/term/2882">Continuum mechanics; nonlinear elasticity</a></div></div></div>Mon, 16 Mar 2015 10:16:41 +0000GuruMech18054 at https://imechanica.orghttps://imechanica.org/node/18054#commentshttps://imechanica.org/crss/node/18054how to model fastners in ABAQUS
https://imechanica.org/node/17851
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>How to model Fastners in Abaqus? I have an assembly which are connected by more than 500 fastners and has angle and channel sections?
</p><p>IS there a method to do in ABAQUS?I have assembled my model in SOLIDWORKS by providing Concetric mating for all drills, but haven't included fasteners there as that will again increase the simulation time.</p>
</div></div></div><div class="field field-name-taxonomy-forums field-type-taxonomy-term-reference field-label-above"><div class="field-label">Forums: </div><div class="field-items"><div class="field-item even"><a href="/forum/357">Computational Mechanics Forum</a></div></div></div><div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-above"><div class="field-label">Free Tags: </div><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/8400">Abaqus 6.12</a></div><div class="field-item odd"><a href="/taxonomy/term/6340"># Finite Element modeling</a></div><div class="field-item even"><a href="/taxonomy/term/935">FEA</a></div></div></div>Wed, 28 Jan 2015 19:10:21 +0000MITHILESH KUMAR DEWANGAN17851 at https://imechanica.orghttps://imechanica.org/node/17851#commentshttps://imechanica.org/crss/node/17851Convergence of Anisotropic Hyperelastic Abaqus-Subroutine
https://imechanica.org/node/17343
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Hello everybody,</p>
<p> </p>
<p>i try to re-implement the anisotropic hyperelastic material of Holzapfel-Gasser-Ogden form already included in Abaqus (cf.<span class="toc"> Analysis User's Manual 22.5.3). </span></p>
<p> </p>
<p><span class="toc">After successfully debugging the subroutine (Uanisohyper_Inv), i had some serious convergence problems, anyhow. My one-element test modelsdidn't even deform a bit.<br /></span></p>
<p><span class="toc">The </span>material uses the Heaviside Step-function to allow fiber-reinforcement only in cases of tension. That causes inconsistencies in the strain enery potential and all of its derivatives. To avoid convergence problems, i use a monotonicly increasing step-function composed of hyperbolic tangent (graph attached). </p>
<p>Now my test-elements deform a bit more, but only until one tenth of the cubes side lengt or so.</p>
<p> </p>
<p>I double checked all derivatives by hand and in Mathematica, debugged successfully with Visual Studio and everything seems to work correctly.</p>
<p>Anyone here, with an idea, what could still go wrong?</p>
<p> </p>
<p>How would the inconsistencies be solved inside the built-in Abaqus material?</p>
<p> </p>
<p>Is there a way to link the object file created within Abaqus to a self-written driver, to check the output of the Subroutine?</p>
<p>I already have the driver, it works great to check the routine without having to start Abaqus. All the variables passed in and out have the right values, but i would like to also check that for the object file created by Abaqus.</p>
<p> </p>
<p>Thanks in advance for every answer!</p>
</div></div></div><div class="field field-name-upload field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><table class="sticky-enabled">
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<tr class="odd"><td><span class="file"><img class="file-icon" alt="Image icon" title="image/png" src="/modules/file/icons/image-x-generic.png" /> <a href="https://imechanica.org/files/step.png" type="image/png; length=5887" title="step.png">hyperbolic tangent step function</a></span></td><td>5.75 KB</td> </tr>
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</div></div></div><div class="field field-name-taxonomy-forums field-type-taxonomy-term-reference field-label-above"><div class="field-label">Forums: </div><div class="field-items"><div class="field-item even"><a href="/forum/109">Ask iMechanica</a></div></div></div><div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-above"><div class="field-label">Free Tags: </div><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/7600">anisotropic hyperelastic</a></div><div class="field-item odd"><a href="/taxonomy/term/8400">Abaqus 6.12</a></div></div></div>Mon, 13 Oct 2014 15:44:07 +0000cclemen17343 at https://imechanica.orghttps://imechanica.org/node/17343#commentshttps://imechanica.org/crss/node/17343Output Spatial Displacement for Specific Nodes in Abaqus 6.12
https://imechanica.org/node/17289
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Hello all,</p>
<p>I am modeling a rectangular steel plate with a hole in the middle. Both the plate and the hole are covered with an anisentropic carbon fiber laminate. The hole is pressurized and both the plate and the laminate are subjected to a biaxial load. I am interested in the spatial displacements of only the nodes on the interior surface of the carbon fiber. (Please see attached picture. I know the mesh is coarse, but I am working on a limited desktop)I know that I can output all the displacements from the entire instance in a report file, but is there any way to output only the displacements of a certain node set or surface? I would just copy and paste the node numbers directly, but Abaqus' node-numbering is difficult to predict and there are quite a few nodes. Any help would be greatly appreciated.</p>
<p> </p>
<p>Thanks in advance.</p>
</div></div></div><div class="field field-name-upload field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><table class="sticky-enabled">
<thead><tr><th>Attachment</th><th>Size</th> </tr></thead>
<tbody>
<tr class="odd"><td><span class="file"><img class="file-icon" alt="Image icon" title="image/jpeg" src="/modules/file/icons/image-x-generic.png" /> <a href="https://imechanica.org/files/Blister_Deformed.JPG" type="image/jpeg; length=239611">Blister_Deformed.JPG</a></span></td><td>234 KB</td> </tr>
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</div></div></div><div class="field field-name-taxonomy-forums field-type-taxonomy-term-reference field-label-above"><div class="field-label">Forums: </div><div class="field-items"><div class="field-item even"><a href="/forum/109">Ask iMechanica</a></div></div></div><div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-above"><div class="field-label">Free Tags: </div><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/8400">Abaqus 6.12</a></div><div class="field-item odd"><a href="/taxonomy/term/10134">Spatial Displacement</a></div></div></div>Mon, 06 Oct 2014 17:47:12 +0000stheisen17289 at https://imechanica.orghttps://imechanica.org/node/17289#commentshttps://imechanica.org/crss/node/17289Thermal contact in CEL analysis in Abaqus 6.12
https://imechanica.org/node/14105
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><span>Hello All!</span></p>
<p><span>I am doing a CEL simulation involving heat transfer (between Eulerian and Lagrangian domains) in Abaqus. The assembly and meshing can be visualized in the figure attached. The Lagrangian part is a rigid ring (can be seen on the right side in the attached figure). The Eulerian material is modeled as a fluid with EOS and viscosity. The Eulerian domain is partitioned, so that it exactly conforms to the ring's cylindrical profile. The analysis is practically 2 D, therefore the model is only 1 element thick.The mesh is quite fine, so that there is no leakage of the material. A gravity load is applied to the whole model. The ring is fixed to prevent translation, but it rotates with a fixed angular velocity in anticlockwise direction. The interface interactions are, "general explicit -> surface pairs (Eulerian material - ring external surface)", "interaction properties -> tangential=rough, thermal=pressure dependent conductance (value 0 at 0 pascals, and 6000 at 0.001 pascals). The Eulerian material inflows at a specified speed in the Eulerian domain from the top left (horizontal face).</span></p>
<p><span>The problem I am facing is that there is insufficient thermal contact at the interface. By visualizing CPress output (for Lagrangian Ring's external contact surface with the Eulerian material), it seems like that the contact pressure is greater then 0 only at very few locations along the interface. Also, it was found that the pressure (in the Eulerian material) drops to negative in many areas (Stress output -> Pressure). Abaqus provides only the possibility of using Pressure dependent thermal conductance behavior at the Eulerian-Lagrangian interface .. therefore I was not able to use the Gap dependent thermal conductance to solve this problem. I tried using Geostatic pressure, but the problem persists. </span></p>
<p><span>The best contact conditions seems to be realized when I prevent any rotation of the ring (based on CPress output for the Ring) ..but even then it was far from perfect. Also, stopping the ring rotation is not the realistic situation.</span></p>
<p><span>As the thermal interaction capability for CEL is relatively new in Abaqus,I was not able to find suitable examples online. I will be grateful if someone could advise me on this.</span></p>
<p><span>Thanks and Regards,</span><br /><span>Paresh</span></p>
</div></div></div><div class="field field-name-upload field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><table class="sticky-enabled">
<thead><tr><th>Attachment</th><th>Size</th> </tr></thead>
<tbody>
<tr class="odd"><td><span class="file"><img class="file-icon" alt="Image icon" title="image/jpeg" src="/modules/file/icons/image-x-generic.png" /> <a href="https://imechanica.org/files/assembly.jpg" type="image/jpeg; length=65690" title="assembly.jpg">assembly.jpg</a></span></td><td>64.15 KB</td> </tr>
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</div></div></div><div class="field field-name-taxonomy-forums field-type-taxonomy-term-reference field-label-above"><div class="field-label">Forums: </div><div class="field-items"><div class="field-item even"><a href="/forum/357">Computational Mechanics Forum</a></div></div></div><div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-above"><div class="field-label">Free Tags: </div><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/5477">cel</a></div><div class="field-item odd"><a href="/taxonomy/term/8400">Abaqus 6.12</a></div><div class="field-item even"><a href="/taxonomy/term/8402">thermal contact</a></div></div></div>Tue, 29 Jan 2013 22:17:02 +0000pareshprakash14105 at https://imechanica.orghttps://imechanica.org/node/14105#commentshttps://imechanica.org/crss/node/14105Error | iMechanica