I had created belt drive mechanism (belt and pulley) assembly in solidworks, I had imported the model to ANSYS. I was looking for a way to vary the belt tension on the pulley and analyze the effect of the belt tension on the pulleys velocity and its health. Can this be done in ANSYS?

I am relatively new to ANSYS and hence I do not have much knowledge on the capability of ANSYS. Any help would be great. Thanks.

]]>I solve a problem with thin shells, with a static calculation I have no problems, when I connect large defomations, I have no solution convergence. How can convergence be improved or what could be the problem?

]]>I have been working with ANSYS mechanical apdl for few months now and I'm modeling reinforced concrete beam with two predifined cracks. Beam length - 2,4 m, heigth - 0,244 m, width - 0,112 m. Reinforcement area - 3,2 cm². Beam has two supports, first constrained in y and x directions, second only in y direction. Beam loaded with two concentrated loads at 0,8 and 1,6 from beginning of the beam. (I attached beam scheme)

I chose 2D plane model and I'm using PLANE182 element type.

For concrete I chose cast iron material model, where I putted stress-strain relationship for compression and for tension. (attached stress-strain relationship diagrams)

For steel I chose multilinear isotropic hardening model. (attached diagram).

I modeled cracks by deleting specific number of elements (attached picture, crack heigth I get from analytical calculation).

For analysis options I chose small displacement static, 20 substeps with aytomatic time stepping, convergence criteria by default.

When I run nonlinear diagnostics, my calulation doesn't converge and I get problem in concrete tension zone, between cracks (attached Newton-Raphson resudual force diagram). in elements events, status of failure criteria in elements, it shows numbers in plastic strain.

What can I do to remove plastic strain limits or anything elso to help to converge solution? Thanks in advance.

I'm studying a masonry arch made of brick and mortar. The contact between these two bodies is "frictional". Having reached a certain value of the applied forces, the solution does not converge (it is as if the collapse of the structure had been reached). My goal was, however, to plot the force-displacement curve, so, I assigned increasing displacements. In this case, however, the solution always converges and, consequently, through "Solution>Insert>Probe>Force reaction", I do not achieve my goal. What do you suggest you do?

Thanks in advance

]]>I am trying to perform an energy harvesting analysis on a structure with 4 piezolecetric patches. I am using ACT Piezo&MEMS Extension. However, I come up with two major errors.

1) I have defined 8 (4x2) voltage couplings for top and bottom surfaces of the patches. When I conduct harmonic analysis, I receive errors such as "**Node 2507 direction VOLT included in coupled sets 5 and 1**". What is the reason of this error? and how can I resolve this problem?

2) I suppressed 7 voltage couplings and kept just one coupling (bottom face of the piezo), and run the harmonic analysis. Now, the solver worked, but this time when I want to plot the voltage frequency response for the remaining piezo, I got this following error.

"**The user defined result might not be calculated successfully wholly or in some areas. There are some elements (or nodes) which do not contain data for the expression in: 133HARMONIC = VOLT**

**Note that the result data may not be contained in the result file or may not be applicable to some element types. Also note that the solver module can create elements, such as surface effect or interface elements, whose results cannot currently be scoped in a contour display.**"

If you help me about these problems, I will appreciate.

Thanks

]]>screenshot of my solver output.

MY APDL COMMANDS

/PREP7

et,matid,CPT215 !define matid to CPT215

KEYOPT,matid,18,2

MP,EX,matid,20000 ! Define Elasticity Modulus (enter a value for E)

MP,NUXY,matid,0.2 ! Define Poisson's ratio

TB,MPLA,matid,,,DPC !Define Drucker-Prager

TBDATA,1,31.6,36.34,3,1,40000,-35 !fuc,fbc,fut,Rt,D,sigVc

TBDATA,7,2,0,2e-5,3000,2000 !R,gamt0,gamc0,betat,betac

TB,MPLA,matid,,,NLOCAL

TBDATA,1,1600,2.5 !nonlocal interaction range c, over nonlocal parameter m

! Replace SOLID185 with CPT215

allsel

esel,s,ename,,SOLID185

emodif,all,type,matid

allsel

! Print out the result:

etlist,all

/SOLU

OUTRES,ALL,ALL

]]>I used harmonic analysis to study the effect of a harmonic force on a plate, Now I would like to ave the results in a table format? ( Displacement by frequency value)

I would like also to have ( displacement by time) is that possible????

]]>Background: from in vivo motion capturing measurments I know the displacements of certain cross section planes inside a bone and I want to derive the stress/strain pattern in the rest of the bone via FEM. Geometric bone models are available.

Thanks

Uwe

]]>I have a very big modell which contains bearings as you can see below. I want to make a global modell to get the deformations and then look in detail with an submodell

fixed bearing:

floating bearing:

I simplified the modell above as you can see below:

fixed bearing area:

floating bearing area:

Then I inserted an bearing joint as you can see on the erxample of the fixed bearing below:

for the floating bearing I inserted following bearing:

Until now I do not know the values for the stiffness, but I hope I will get them from SKF. My main problem is that I am not sure if I modelled the bearing correctly?

Thank you for your answer and best regards,

bokaJ

]]>Could u please advise what could have gone wrong?

]]>I am trying to mesh a pipe assembly.

When not applied shared topology multizone meshing is successfull

But to avoid non conformal meshing i want to use shared topology

But after applying shared topology in spaceclaim the following error encountered.

If i try to mesh one part only the following error message is encountered

This kind of deformed mesh is generated

I am using the following mesh setting

Request help to sort out the problem.

]]>Using 1 iteration per substep may result in unconverged solutions for

nonlinear analysis and the program may not indicate divergence in this

case. Check your results.

]]>I want to find out the mean contact pressure of two bodies. Below you can see the contact pressure with the display option "averaged".

Below you can see the contact pressure with the display option "unaveraged".

These two solutions are nearly the same, so I think that my mesh is fine enough.

I want to find out the force at which the mean contact pressure is less than 50MPa. So I set Contact Misscellaneous and Nodal Forces to YES at the output controls.

I inserted a force reaction where I choose for Contact Region the contact I am intereseted in. I get following solution:

When I divide the Force reaction of 63809N throug the contact area of 782mm^2 I get 81,6N/mm^2. But when I look at the contact pressure above, I think that that can not be true. In my opinion this is way too high.

You can see my contact definition bellow:

You can see the contact area below:

Can anyone help my the get the mean pressure of my contact or has an idea what I have done wrong?

Thank you an best regards,

bokaJ

]]>I want to know the deflection and the stress of a very big modell.

Therefore I will calculate the deflection of the whole modell and then look at the importent areas closer with submodells.

The modell is an welded construction. There are many welds like shown on the following picture and I am not sure how to modell them in ansys.

I made an sketch to show you my idea of modelling this problem.

I will divide the frontal area of the beam in 3 areas and connect the red ones with an bonded contact to the wall and the blue one with an frictionless contact to the wall. Or is it enough to connect just the outer edge of the beam with an bonded contact to the wall and the frontal area with an frictionless contact to the wall?

Can anyone tell what is the best practice to solve such a problem?

Thank you very much and best regards,

bokaJ

]]>I am simulating a large rotating flywheel which has a hole in it, that causes stress concentration. I have simulated the condition and obtained results. Now the issue is, I want to verify it analytically. What formulae do I use? Can someone explain the concept? or can anyone suggest me some good literature to understand the analytical calculations?

]]>Also, after modal analysis natural frequencies doesn't match with the numeric model.

What could be my mistake? :(

]]>@peteroznewman and all

Could anyone please tell me procedure or design schematic of this paper. How can I Implement this paper in ANSYS?

https://ieeexplore.ieee.org/document/1563262

I know how to find the collapse voltage. And I know the procedure of applying prestressed condition But I am facing problem with Acoustic pressure graph.

In this paper, they have X-axis in KPa/V. What is it? I know acoustic pressure in KPa. And here I have attached ANSYS file which I have implemented. I got all result in MPa and It's huge.

Could you please help me with getting that graph? I am interested in Fig. 14 graph

Am I on right track or not? Please suggest me I tried all things but I don't where I am doing wrong.

I used ANSYS Workbench 2019 R2 academic(research) licence.

Here I have attached workbench file.

Thank you so much

Regards,

Dhruvin

]]>I am doing acoustic analysis for Capacitive Micromachined Ultrasonic Transducer. and the goal is to find average pressure on the membrane.

I am referring this paper for simulation: https://ieeexplore.ieee.org/document/1563262

As you can see in the figure, I have performed prestressed harmonic analysis on a single cell. I applied 80% of collapse voltage (80% of 135 v =108 v) in static analysis. then I have applied 1 v AC voltage in harmonic analysis. later on, I have done an acoustic harmonic analysis. I got a different plot for acoustic pressure on the membrane.

Now my question, should I have to implement linear periodic symmetry? In the paper, they wrote "Assuming symmetry boundaries in the width dimension will further simplify the modelling of CMUT arrays. The corresponding transducer will be infinitely large in both lateral dimensions."

How can I implement that?

and why I got the highest pressure on a different frequency?

Even I upload my question in the discussion forum.

I tried to implement linear periodic symmetry but I am not able to do it.

Here I have attached workbench file.

Thanks and Regards,

Dhruvin

]]>I want to analyze a shaft system for coupled axial and torsional vibration. I know the masses and inertias as well as stiffness and damping coefficients. I understood how the model system for torsional vibration but the thing I couldn't understand is how can I define 2 combine 14 (one is for torsional and one is for axial) to one line?

]]>I want to change material property by using apdl commands snippets. I assign a material property at the beginning and change it in analysis setting. like this

in that command section , I type

FINISH

/PREP7

*GET, maxMaterial, MAT, 0, NUM, MAX

maxMaterial = maxMaterial+1

mp,ex,maxMaterial,10000

mp,nuxy,maxMaterial,0.45

mp,nuxz,maxMaterial,0.45

mp,nuyz,maxMaterial,0.45

cmsel,s,target

mpchg,maxMaterial,all

FINISH

/SOLU

my displacement is set to 3mm. the program could run successfully, however, the result seems nothing moved.

I want to know what happed in this processure

]]>I want to get the maximum force wich I can put on a can of coke until the structure collaps.

Therefore I started an explicit dynamic analyse. Bellow you can see my model:

I used a shell for my can and on the top and on the botton there is also a shell. You can see my contact bellow:

The shell on the botton is fixed with a body-ground joint.

The upper shell has a displacement as you can see below.

The model works pretty well, but the deformation does not look really realistic. In abaqus you can put imperfections at the structure so that the model buckels more realistic. I hope that my reaction force gets also more realistic then. Can anyone say me how I can model these imperfections in ansys?

Tahnk you very much

bokaJ

]]>Below are some screenshots from my test model. I've modeled two fixed cantilevers. One is pressed with force downwords. I would like to add node to node contact which will transfer only compressive force and allow for sliding.

I made some trys in classic apdl and try to repeat it in command snippet. But in nither enviroment i didn't achieve result that I've expect.

As you can see on below plots there are lines defining the contact. But there is no reaction of the lower cantilever. It looks that there is some problem with KEOPTS..

I've got two question

1) What setup to use in KEYOPT of CONTA178 to achive node to node contact described above ?

2) Is there any node to node contact eqivalent inside Workbench ?

Thank you in advance !

Regards !

]]>Related on topics (https://forum.ansys.com/discussion/23188/ansys-vs-asme-b31#latest), I got some following issues about Ansys Result vs ASME B31

- Which are more reliable, using Principal Stress (Normal Stress) or using customized result bsen on Von Mises (Von Mises stress divided by 2)?
- How to create customized result based on Von Mises Stress. It is need to divide the Von Mises result by 2

Thank you in advance

Husain

]]>I have a problem with my structural analysis.

I want to simulate 2 metal plates which are bolted together, as you can see in the following picture.

The one end is fixed. On the other end there is a force into the direction of the plate strip (5000N). There is also a force in the direction of the bolt (5000N) on the upper und on the bottom side of the plate.

At first I made a hand calculation. The section of the plate is 40mmx5mm.

So I get a normal stress on the upper side of the left plate of about -125N/mm^2 and a normal stress on the bottom side of about 175 N/mm^2.

The right plate shoud have stress about 25 N/mm^2.

I have modelled this at first with 3D elements and got also these results.

Now I wanted to model it with shells and a beam instead of the bolt. But now I get results, which can not be true.

You can see my geometry at the picture bellow:

I connected the circular ring shell, wich presents the bolthead with the plate with a bonded contact. Also the 2 rectangular plates which presents one plate are bonded together. The areas of the 2 plates which are bolted together are connected with a frictional contact. The endpoint of the beam is connected with the "bolthead" with a fixed joint.

At the first step I obtained the bolt pretension and on the second step I obtained the forces on the plate.

So I get normal stresses as you can see bellow:

The results on the right plates are correct. But I think my results for the left plate are incorrect. But I have no idea what I did wrong.

Maybe I need more integration points for the shell? But unfortunately I did not find, where I could change this in ANSYS?

I am really looking forward for answers and ideas.

Thank you very much

bokaJ

]]>In the above picture I show how I successfully ran a multistep temperature load and solved the von-mises stress over time. However, I am trying to figure out if there is a way to export the load history per node for the fatigue life analysis(fatigue tool) as I believe it is only calculating the final time step zero based loading. If I do the history based the on the maximum stress vs time load graph does it apply this singular max stress load to every node in the mesh?

]]>Moving forward I plan on using a displacement function to create the reciprocating motion. My problem is I believe I cannot do this under the axisymmetric setting, so I made the top surface axisymmetric, and the bottom surface plane stress with my desired thickness (This would be the surface I apply displacement to). Now I no longer obtain the correct hertzian contact (when the model is stationary).

Questions:

Do you think it is possible to create the model as I am describing in 2D analysis? (I would like to avoid 3D)

Do you have any suggestions on how I can setup the model so that I still get the correct hertzian contact stresses, and can also still implement reciprocating motion?

Thank you.

]]>Related on topics (https://forum.ansys.com/discussion/23188/ansys-vs-asme-b31#latest), I got some following issues about Ansys Result vs ASME B31

- Which are more reliable, using Principal Stress (Normal Stress) or using customized result bsen on Von Mises (Von Mises stress divided by 2)?
- How to create customized result on Ansys Workbench Structural based on Von Mises Stress. It is need to divide the Von Mises result by 2

Thank you in advance

Husain

]]>Is it possible to use PML (perfectly matched layers) withing ANSYS Workbench environment ?

In APDL we can use PSYS command for this.

I am trying to use this for Soil-structure interaction problem and in APDL it is possible. But trying to figure out how can i integrate into workbench .

Thank you very much

]]>How can I create a volume to which I will apply a load and this can be transferred to the structure (that supports this volume) this volume should not participate in the design?

]]>I am trying to solve a single arched masonry bridge using an acceleration record. For masonry elements, I used CTP215 finite elements. In the model, there are three structural elements, ARC, SPANDREL WALLS, and FILLER material. I modeled all of them bonded to each other. In order to make the solution easy, I assigned the same material properties to all structure portions. Although I use an acceleration record of 3 s under transient analysis I could not get convergence.

Any help on how to overcome such a convergence problem is appreciated.

Many thanks in advance.

I want to perform a coupled thermal structural analysis. For this, I doing the transient thermal analysis first and then I am importing the temperature results to the structural analysis. The structural analysis has only temperature loads and a fixed support at one face. But I could not decide whether to use static structural or transient structural in this case. I know that in transient structural, the inertia effects are considered but how do I find out if the inertial effects are significant or not in my system? My model is big and hence when I try to perform transient structural, it takes days to solve it.

I have already gone through the Ansys documentation pages on the analysis explanation. I would appreciate any help that would help me understand it better.

Thanks!

]]>residual stresses gained by plastic loading before working process

How can i take the residual stresses results and put like prestressed in the work process

2 stages we cannot mix them but results related

]]>I am trying to simulate the response of a thin diaphragm attached to an open cylindrical cavity to a harmonic pressure. The cylindrical cavity is of 1 mm height and 1 mm diameter, with the top cavity wall replaced by a flexible thin diaphragm of thickness 10 microns. The other walls of the cavity are rigid. The diaphragm is subjected to a harmonic pressure of, say, unit magnitude within the audible range (20 Hz to 20 kHz). The aim is to find the vibration response of the diaphragm and the air pressure inside the cavity.

a) How do I model the cavity? My first thought was to create an enclosure below the diaphragm of the same dimensions as the cavity, but I am not sure if enclosures work that way since it doesn't 'enclose' anything.

b) Assuming I am able to geometrically model the cavity and the diaphragm, how would I create the interface between the two to perform a coupled analysis?

Thank you.

]]>Thanks

]]>I am trying to solve a shaft and cylinder kind of problem in static analysis. Can I see the movement of the cylinder using static analysis or should I have to use transient analysis?

As i was instructed to use static analysis since only small sliding is possible in my analysis. But when i use no separation contact in my simulation i can not observe any displacement. Can anyone please let me know what is the problem.

]]>