opethian
Mechanical
- Nov 3, 2005
- 20
hi to all
We are try'n to make a thermal analyze aprox. 15 cm long heavy exhaust
Manifold head and part of engine block where the part is attached.
Problem that we encountered recently is excessive preload at the bolt neck.
In the model we have pre-load at the middle section and bolt is tied to engine block from below and there is a contact between the
bolt head and exhaust manifold.
Our questions are;
1 ) what is the possible reason of having 3000 MPA stress value ( is it that important value to care that much )
just for preload step with a preload value of 41600 kN for M10 bolt?
2 ) just for a trial we add a test load as a pressure from the turbo section that causes bending over the bolts for any pressure value, and our contacts in the model do not converge.
So, solver does not go through the load step after bolt load step .
Although we have tried to change master and slave surface definitions and tried different type of contacts for our contact regions, unfortunately we did not get a satisfactory result yet.
Contact definition still seem to be a problem for 6.7 version of abaqus but anyway may be one of the most difficult part of simulation for all CAE programs.
Thanks for you replies.
Write you soon.
We are try'n to make a thermal analyze aprox. 15 cm long heavy exhaust
Manifold head and part of engine block where the part is attached.
Problem that we encountered recently is excessive preload at the bolt neck.
In the model we have pre-load at the middle section and bolt is tied to engine block from below and there is a contact between the
bolt head and exhaust manifold.
Our questions are;
1 ) what is the possible reason of having 3000 MPA stress value ( is it that important value to care that much )
just for preload step with a preload value of 41600 kN for M10 bolt?
2 ) just for a trial we add a test load as a pressure from the turbo section that causes bending over the bolts for any pressure value, and our contacts in the model do not converge.
So, solver does not go through the load step after bolt load step .
Although we have tried to change master and slave surface definitions and tried different type of contacts for our contact regions, unfortunately we did not get a satisfactory result yet.
Contact definition still seem to be a problem for 6.7 version of abaqus but anyway may be one of the most difficult part of simulation for all CAE programs.
Thanks for you replies.
Write you soon.