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x-momentum not converged; co-simulation

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srimanishreddy

Automotive
Mar 12, 2018
13
Hello guys,

I am trying to simulate an FSI with an oil film in between chain joint using Abaqus Co-simulation.
I was able to successfully simulate the structure
step 1: pretention with 20N concentrated load.
step2: rotation on 30rad/sec with 240 N load on the bushing.

The oil film is present in between the pin shaft and bushing.

Oil film properties: density and viscosity are given (values are taken for SAE 10W 40 at 50 deg) dependent
BC's: inlet pressure, wall no slip, outlet pressure, initial density as predefined BC
mesh: tet with boundary layers 15 on each side of the film.
step time: 0.2 for the structural model and fluid model.

When I try to simulate, the momentum solver does not converge as the film thickness is too small and highly viscous, loads from the structure. So I have changed the iterations to 250 for momentum solver CFL still being 0.45.

Solvers for CFD: pressure: preset 3, 0.001-time increment
momentum: default but the iterations are changed to 250
transport: default
Keyword input: controls for implicit mesh smoothing and FSI stabilization with FSI penalty scale factor as 1.2, solid/fluid ratio: 9.07

After these changes, the RMS on the monitor shows to be between 0.3-0.9. And solver solves it for so long with very less increment size and still, the x-momentum do not converge.

Any suggestions and information regarding how I can achieve a solution.

ABAQUS_1_kfa41k.png

ABAQUS2_vlzjhm.png

ABAQUS3_vuwprk.png
 
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