## I have a problem on the software ansys,i change the Young modulus but the stress still the same ?

## I have a problem on the software ansys,i change the Young modulus but the stress still the same ?

(OP)

I have a problem on the software ansys,i change the Young modulus but the stress still the same ?

## RE: I have a problem on the software ansys,i change the Young modulus but the stress still the same ?

## RE: I have a problem on the software ansys,i change the Young modulus but the stress still the same ?

I know that Stress=Young modulus*déformation, that's why i expected a variation of the stress

## RE: I have a problem on the software ansys,i change the Young modulus but the stress still the same ?

And what happens to Strain if you, for example, double Young's Modulus ?

you mean that i have to declare the poisson coefficient value to perform my analysis ? the stress remains the same if i just change the young's modulus ?

Can you give me more explication

In FEA, you will get the different deflections due to change in Modulus but stress will remains same since you have not changed area or force. Software first calculates the deflections but modulus remains neutral to calculation.

(σ=E*ε=E*(Force/Area*E)=Force/Area)

"I have two rods with 1 cm^2 cross section area, one made of steel another from cooper. Tensile force of 100 N applied to both rods. Where the stress will be larger and where smaller?"

The simple answer is stress will be equal.

More precise answer is stress in copper rod will be larger, but difference will be very very very small.

P.S. Hivemind in eng-tips)

please find attached the screen of my model and give me your point of view ( 3 cases of temperature nedeed 100 , 230, 350)

I can perform thermal (uniform temperature) + structure analysis in order to determine this type of stress ?

because i tried and it gived me high stress value (what i have to check ?).

please find attached the screen to undrestund what i mean.

Thank you

linearformulation also dont depend from E, only from geometry. Post here model to see what is constraints of detail. All your model is blue, the hot spot mau occure at constraint point or due to singularity - in both cases you can neglect this stress because it is nonphysical.i need to simulate the membrane + bending stress in 3 case of temperature as i said previously.

Run command File->Archive, wbpj file is only index of geometry and mesh files and uncheck option Results/solution to minimize file size.

As for your problem - what is the point of interest - stress and displacement due to force - then you can calculate three values of E for each temperature or in addition, you want to see stress/displacement condition at lower surface?

In first case, you can neglect thermal stress near constraints because it is nonphysical.

In second case, you must model real connection between detail and ground, you must model some portion of grounding structure - move boundary conditions far away from zone of interest - it is one of basic principles of FEA, CFD and all computational physics, as I say Saint-Venant's principle.

Better, make simple model, if you have some privacy issues, and post in here, better to solve problems together.

I`m 95% sure that you don’t need thermal load - use different E. However, I can only suggest. Nobody know the problem better than you.

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