Abaqus CEL: Eulerian Fluid is leaking through lagrangian solid. Why???

Hello everyone,

in the past, I had succeeded running a coupled eulerian lagrangian (CEL) method simulation using abaqus. Now I would like to run another CEL simulation, but something is going wrong and I could not find out what. The fluid, that is modelled as eulerian element, is flowing through the solid (lagrange element), although I have assigned a general contact interaction to it. I would be really grateful, if someone could give a look to the input file (1-CEL) and could give me a hint, how to avoid the leaking.

I also upload another input file (job-7d) containing a functioning CEL simulation.

Thank you everyone for any input.

Best regards,

Gunardi

Link to files:

http://files.engineering.com/getfile.aspx?folder=502637a8-1130-44fa-af6f-ef388368706a&file=1-CEL.inp

http://files.engineering.com/getfile.aspx?folder=c7449f37-ccca-43a1-af02-53c3f44136c3&file=Job-7d.inp&__hstc=212727627.605951e7522ce04878397c341970d2b5.1488929773011.1490291812957.1491427418810.14&__hssc=212727627.11.1491427418810&__hsfp=3017310608