## Thermal stress analysis

## Thermal stress analysis

(OP)

Hi frds,

I am using ABAQUS CAE 6.6-1

I am simulating a Shell subjected to a temperature change(for eg., 350 to 500deg C) and with some mech BCs.

I am able to do this in a static step ,by giving initial temperature field in initial step(for eg., 350deg in predefined field1 in initial step)and and in the static step have given final temp as field 2(500deg in predefined field2 in static step)with some mech BCs.

In my results i am obtaining the temperature distibution over the step time(350 to 500deg C)

Now I want to do this as Sequential thermal stress analysis

I have modelled two different Heat transfer models with Temperature BC in Heat transfer sterand obtained two odb files got distribution of initial and final temperatures respectively(for eg.,initial odb file contains 0 to 350 deg distributionand eg.,final odb file contains 0 to 500 deg distribution)

I modelled a static analysis model and getting initial odb file in initial step predefined field and final odb file in static step as predefined field 2 with mechanical BCs.

But i am getting different stress and displacement values for both(Static models simply with temperature field and Sequential analysis(Static models with the results of heat transfer models))

I dont know why, may b the element type chosen in Heat transfer and Static in sequential analysis(i hav also tried changing suitable elements but there is no change)

hope i hav explained it in detaillll

Is there anyother way to obtain the tempeature distribution in the static step?

thx for reading the long story

i am waitig for your suggestion thx

I am using ABAQUS CAE 6.6-1

I am simulating a Shell subjected to a temperature change(for eg., 350 to 500deg C) and with some mech BCs.

I am able to do this in a static step ,by giving initial temperature field in initial step(for eg., 350deg in predefined field1 in initial step)and and in the static step have given final temp as field 2(500deg in predefined field2 in static step)with some mech BCs.

In my results i am obtaining the temperature distibution over the step time(350 to 500deg C)

Now I want to do this as Sequential thermal stress analysis

I have modelled two different Heat transfer models with Temperature BC in Heat transfer sterand obtained two odb files got distribution of initial and final temperatures respectively(for eg.,initial odb file contains 0 to 350 deg distributionand eg.,final odb file contains 0 to 500 deg distribution)

I modelled a static analysis model and getting initial odb file in initial step predefined field and final odb file in static step as predefined field 2 with mechanical BCs.

But i am getting different stress and displacement values for both(Static models simply with temperature field and Sequential analysis(Static models with the results of heat transfer models))

I dont know why, may b the element type chosen in Heat transfer and Static in sequential analysis(i hav also tried changing suitable elements but there is no change)

hope i hav explained it in detaillll

Is there anyother way to obtain the tempeature distribution in the static step?

thx for reading the long story

i am waitig for your suggestion thx

## RE: Thermal stress analysis

are doing, and I do not have yet v6.6, my comment is

that in the Static step, the heat trasfer problem is not solved for. The temperature fields are used only for computing the thermal strains. The temperature fields have a prescribed variation in the static step.

If you put an initial temperature field in a heat transfer step (transient or steady state), the heat flow will be accounted for .

## RE: Thermal stress analysis

will yos suggest me a suitable step for doing my analysis?

thx

## RE: Thermal stress analysis

## RE: Thermal stress analysis

corus

## RE: Thermal stress analysis

## RE: Thermal stress analysis

(If quad=quadrilateral element then by linear elements you mean (bi-)linear quads and by quads you mean (bi-)quadratic quads, don't you ?)

## RE: Thermal stress analysis

I'm firstly simulating a plane strain problem under a uniforme thermal field at steady state. It is evident that this problem can be given in a closed-form, but I don't know how to introduce in Abaqus the thermal boundary conditions (ex, thermal-isolating wall at steady-state, T(left-side)=Tl, T(right-side)=Tr) or other treatments... Someone can help me?

I've read documentation: *COUPLED TEMPERATURE-DISPLACEMENT,steady state. ....but it seems that it not run.

Thank a lots.

## RE: Thermal stress analysis

## RE: Thermal stress analysis

## RE: Thermal stress analysis

thx for all ur replies sorry for the late response

i found the solution

the problem was that the number of temperature points in thermal file does not match the mechanical files

i need to specify it as piece wise linear to the number of integration points. it will be done in the Section in advanced tab option.

thx for all ur comments

bye

sheriff