Error: NO DATA CARDS PROVIDED FOR *FLUID CAVITY

[ylu]

Hi, ABAQUS Users,

Based on a input file, I add the following lines to define fluid cavity(Ref node and surface have been defined):

*physical constants, absolute zero=-273.16, universal gas constant = 8.314
*fluid cavity, name=fcavity, behavior=gas, ref node=1000,surface=ASSEMBLY_SURF, ambient=1.0136e+5
*fluid behavior, name=gas
*molecular weight
0.044
*capacity, type=tabular
30

But this doesn't work in ABAQUS, the dat file generated by ABAQUS suggests:

*fluid cavity, name=fcavity, behavior=gas, ref node=1000,surface=ASSEMBLY_SURF, ambient=1.0136e+5

***ERROR: NO DATA CARDS PROVIDED FOR *FLUID CAVITY


THE PROGRAM HAS DISCOVERED 1 FATAL ERRORS

** EXECUTION IS TERMINATED **


What's meaning of No Data Cards?
Any comments will be appreciated.

Yiling

 

[Carlosjmr]

hello!

well, i had tried the same problem, and you have to let a blank line to abaqus write something!

i can't tell you right now where you have to let the blank line, but if you send me the file, i can try it.

best reguards.

 

[Carlosjmr]

hello once again,
first, you have to define the fluid behavior inside the instance space.
then, you define the fluid cavity outside the instance space, like this

......
*end instance
......
*fluid cavity, name=........
(blank line)
the name of the fluid behavior.

i try to explain this, but it's not so simple to do that.
i hope you can get this right.
best reguards

 

[ylu]

Dear Carlosjmr,

Thank you for your advice. I have already made it run.
Yes, you are right, we have to leave a blank line following the keyword line *fluid cavity. I am using an input file ignoring the archetecture of finite element model(i.e. instance, part, assembly). So the position of fluid cavity and fluid behavior definition doesn't matter as long as it lies inside the model data.

Are you familar with the definition of fluid property? I don't know how to define the fluid bulk modulus for incompressble fluid in a fluid-filled cavity. In theory it should be infinite. Do you have any experience to share? Currently I am using a value 2.2x10⁺⁹ Pa for water, which is obtained from the internet.

Thanks,

Yiling