Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations pierreick on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Abaqus- Temp-disp coupling analysis- sequential steps used.

Status
Not open for further replies.

nikhilmohan

Aerospace
Jun 4, 2015
1
Hi everyone,
I have to do thermal-mechanical coupling analysis of a cantilever beam where several steps are present.
STEPS:
1. HEATING ( from 25 deg C to 130 deg C)
2. LOADING (1.3 MPa)
3. COOLING (before cooling i am holding the free edge of the cantilever and cooling down the temperature to 25degC)
4. UNLOADING (before removing load i am unholding one edge and same magnitude load is applied in opposite direction)
5. HEATING (holding both the edge and i am heating again to 130degC)

I have done the analysis till the second step. But in third step i am encountering a problem. In COOLING step i suppose to change the reference temperature to 130degC from 25degC. But in HEATING step reference temperature should be 25degC.
I am unable to find out a way to change the material values in different steps. Can anyone help me?
I have attached .cae file here.

Note: I am using temp dependent young's modulus and expansion coefficient with ref.temp=130degC.
Problem : stress value is shooting up to 97 MPa in cooling step. But analytically the value should be around 8.6 MPa.
 
 http://files.engineering.com/getfile.aspx?folder=4623d894-f9d6-45dc-bd3c-351a41732e86&file=thermo-mechanical.cae
Replies continue below

Recommended for you

Hi everyone,
I have to do thermal-mechanical coupling analysis of a cantilever beam where several steps are present.
STEPS:
1. HEATING ( from 25 deg C to 130 deg C)
2. LOADING (1.3 MPa)
3. COOLING (before cooling i am holding the free edge of the cantilever and cooling down the temperature to 25degC)
4. UNLOADING (before removing load i am unholding one edge and same magnitude load is applied in opposite direction)
5. HEATING (holding both the edge and i am heating again to 130degC)

I have done the analysis till the second step. But in third step i am encountering a problem. In COOLING step i suppose to change the reference temperature to 130degC from 25degC. But in HEATING step reference temperature should be 25degC.
I am unable to find out a way to change the material values in different steps. Can anyone help me?
I have attached .cae file here.

Note: I am using temp dependent young's modulus and expansion coefficient with ref.temp=130degC.
Problem : stress value is shooting up to 97 MPa in cooling step. But analytically the value should be around 8.6 MPa.
 
Why don't you add additional material data at other temperatures? Just add lines to create a table of these data. That's possible for nearly all kinds of material data.

Example at linear elasticity:
210000, 0.3, 20
200000, 0.29, 100
180000, 0.27, 200
:
:
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor