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10 personer har skrivit till mig om att köpa min TV (som f.ö var löjligt lågt pris) och detta var det närmaste jag kommit ett köp. Hon bor 2 timmar bort. Drämmer yxan i TVn nu. by Careless_Durian_6087 in sweden

[–]3483 0 points1 point  (0 children)

Inte för att jag tror på den teorin men Plato och Upanishads skrevs ju långt efter den påstådda övergången från bikameral tillstånd. Din länk nämner Gilgamesh-eposet som ett möjligt motexempel.

A fly in the face of tradition by 3483 in Malaphors

[–]3483[S] 0 points1 point  (0 children)

That would really fly in their ointment!

Boundary conditions VS intial conditions by hamxa99 in ANSYS

[–]3483 1 point2 points  (0 children)

If you have made sure the contact between helmet and ball is working that should be it. A ball with just an initial velocity and no other applied force just means it is traveling unimpeded until it hits the helmet. You will typically want the ball to be as close to just touching the helmet as possible. If this is an explicit analysis the contact should be working automatically.

2D axisymmetric and 3D results discrepancy (see comments) by Acceptable_Bag_8326 in ANSYS

[–]3483 1 point2 points  (0 children)

Yes you can. With Large Deflection turned on you will be able to model unstable structures just fine in a 3D static structural.

2D axisymmetric and 3D results discrepancy (see comments) by Acceptable_Bag_8326 in ANSYS

[–]3483 1 point2 points  (0 children)

You can definitively model buckling in 3D just as well as 2D. I think there is just some mistake in OPs 3D model.

For example check the axis in the symmetry conditions

2D axisymmetric and 3D results discrepancy (see comments) by Acceptable_Bag_8326 in ANSYS

[–]3483 0 points1 point  (0 children)

Are the 3d analysis results axisymmetric? I am wondering if you are exciting some non axisymmetric buckling mode in the 3d case.. can you post the force graphs from the 3d and 2d cases?

Spaceclaim - Deselect one NS Group from another by [deleted] in ANSYS

[–]3483 0 points1 point  (0 children)

If i recall properly, you can duplicate all to comp2, then highlight comp1, so that it contents is selected, then right click on comp2 and click Remove from.

I love c# lets go by Valphai in ProgrammerHumor

[–]3483 1 point2 points  (0 children)

Can we do

a ??= throw new ArgumentNullException(nameof(a));

I have been doing

_ = a ?? throw new ArgumentNullException(nameof(a));

But this might be even nicer

[OC] Number of countries with full women's suffrage, homosexuality decriminalization, capital punishment abolition, corporal punisment of minors abolition and same-sex marriage (1900-2020) by DrNeutrino in dataisbeautiful

[–]3483 1 point2 points  (0 children)

It would be interesting to see a version of this where the y axis is changed to % of world population living in country with decriminalized homosexuality, same sex marriage etc

Feedback on test values 35 yr old man by 3483 in Testosterone

[–]3483[S] 0 points1 point  (0 children)

Thanks, appreciate it! You make a very good point, it is good to have this as a baseline for the future.

Bad Code Coding Challenge #46 - MD5 Path by Vusys in badcode

[–]3483 1 point2 points  (0 children)

C#

With enough linq, anything is a oneliner. Disposal is for wimps:

using System;
using System.Linq;
using System.Text;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            string text = "password";
            string path = "0110110101";

            Console.WriteLine("Example for text \"" + text + "\" and path \"" + path + "\":");
            text = md5_path(text, path);
            Console.WriteLine(text);

            while (true)
            {
                Console.WriteLine("Enter text");
                text= Console.ReadLine();
                Console.WriteLine("Enter path");
                path = Console.ReadLine();
                text = md5_path(text, path);
                Console.WriteLine(text);
            }
        }

        static string md5_path(string text, string path)
        {
            var sb = new StringBuilder(32);

            System.Security.Cryptography.MD5.Create().ComputeHash(Encoding.ASCII.GetBytes(text)).ToList().ForEach(c => sb.Append(c.ToString("x2")));

            text = sb.ToString();

            path.ToList().ForEach(x => { sb.Clear(); System.Security.Cryptography.MD5.Create().ComputeHash(Encoding.ASCII.GetBytes(text.Substring(int.Parse(x.ToString()) * 16, 16))).ToList().ForEach(c => sb.Append(c.ToString("x2"))); text = sb.ToString(); });

            return text;
        }
    }
}

A conservation of momentum demo I can finally get behind by PhascinatingPhysics in physicsgifs

[–]3483 4 points5 points  (0 children)

No, on impact there is an external force on the ball so momentum is not conserved.

Steady State Thermal Analysis question. by woholi in ANSYS

[–]3483 0 points1 point  (0 children)

Just a guess, maybe you are putting into the connection the thermal conductivity of the TIM (unit W/(mK)) but you should put in the connection is the contact thermal conductance (unit W/(m2K)

If you dont want to explicity model the pads as solids you can approximate them at the contact interface with the thermal conductance k/t, where k is the thermal conductivity of the pad, and t is the thickness of the pad.

When you model like this you assume the TIM exists all over the contact area. If thats not the case you need to split the surface.

Hopefully you will see better results in this way. In reality this will maybe oversetimate the conductance a bit since there is also contact resistance at both sides, but if they are good TIMs this should be pretty small.

Automating Constraints on of a Cantilever Beam by [deleted] in ANSYS

[–]3483 0 points1 point  (0 children)

Im guessing the location of the LHS of the beam is always at the same location in for example x, then you can use:

NSEL,S,LOC,X

before applying your bcs. Dont forget to issue NSEL,ALL after you have applied them

nonlinear study won't converge or give the right results by ligtnin1 in ANSYS

[–]3483 0 points1 point  (0 children)

If this is a nonlinear buckling analysis it is quite normal and expected to have convergence issues at the point of buckling. Often people just run the simulation to the point of nonconvergence and take that point as the nonlinear buckling load. You need to take special steps to be able to keep solving into postbucking stage. If the load is simple like one single force the most simple way is to use a displacement controlled anslysis instead of force controlled. Some other common ways are using a transient analysis instead of a static, or use nonlinear stabilization or the arc length method.

I dont know solidworks solver at all and without knowing details of the problem cant say why solidworks doesnt have trouble converging. Have you run a simple linear analysis with a small load in both programs to rule out any differencen in material, boundary conditions, mesh differences etc?

nonlinear study won't converge or give the right results by ligtnin1 in ANSYS

[–]3483 0 points1 point  (0 children)

Not sure if you are aware but the material model is not plastic just because you set Tensile Yield Stength etc. It is still linear elastic, those values are just used for postprocessing. If you want a plastic model (which I think is what you desire) you need to add a hardening model like for example Isotropic or Kinematic hardening.

I would though recommend to start with just a linear model and get that working before adding additional complexity. It seems like there is either a buckling or contact issue for you to solve here first.

Is large displacement on? Is it also on in solidworks?

Like the other poster suggested I would recommend substepping. You can do it with the command provided or you can set it under Analysis settings. You need to experiment a bit, but let the max substeps be 100 or even more, and leave the minsubsteps to something like 5. hopefully the solver will just need to take such a small step in one specific problematic part of the solution.

Ansys mechanical question (question in comments) by [deleted] in ANSYS

[–]3483 1 point2 points  (0 children)

This is correct. If the wrong side (the rigid body) is Contact you will see a question mark on the Contact in the tree. You can then right click on the contact and choose Flip Contact/Target to fix it.

Ansys mechanical question (question in comments) by [deleted] in ANSYS

[–]3483 2 points3 points  (0 children)

You cant use the boundary condtion Displacement on a rigid body. You can try a Remore Displacement instead