What is ERROR ID: 400?

Altair Forum User

Hi guys

 

I'm trying set up a model of a ditching body in water, modelling Water by Smoothed Particle Hydrodynamics. And i would like to model just an half

of entire model applying symmetry conditions.

By using /SPHBCS card for the sph symmetry conditions, i select a frame i have previously created, that defines

the symmetry plane by the /DIR value.

But running radioss it gives me this error

ERROR ID :          400
** ERROR IN SPH CONDITIONS (FRAME)
DESCRIPTION :  
   UNDEFINED REFERENCE FRAME ID=1

What could be the reason? maybe i mistake something creating the system or imposing symmetries for SPH elements?

 

Thanks to All

 

D.M

Altair Forum User

Hi D.M,

 

The system which you referred in the SPH/BCs should be a fixed reference frame.

 

Make sure you have create the system based on axis and direction instead of creating using node reference.

Altair Forum User

Thanks Prakash

 

I have tryed with 'CREATE WITH AXIS DIRECTION' but it gives me the same error, maybe i mistake something in the procedure

Start model is composed of components, materials, properties, loadcollectors, curves...all created in global initial system

then what i do is this:

i go in SYSYEM panel > CREATE WITH AXIS DIRECTION > select the origin node, select the node to define x axis, select the node to define xy plane > rctangular > Create

I have placed the node i used as origin in the symmetry plane that i need

Then i update the /SPHBCS with the frame_id i have just created ( the value of DIR now reffers to the new frame) > Return

that's it...what do you think?

Have i to assign SPH nodes in the systems panel by the assign option avaible, to the system i have created?

 

I have noticed, that if i build the entire model with the origin of initial global system exactly in the center of model, and then i use its axis to define the

DIR parameter in SPHBCS, the symmetry seems to work quite good (i have to check it plotting some values referred to the same node both of entire model and of half model with symmetry).

 

Regards Prakash

Altair Forum User

Resolved

I was mistaken  creating the frame by systems panel; I needed follow this path Tool > Create Card > Frame > Fix

and then select Origin, X axis and XY plane...Right?

Altair Forum User

Hi,

 

Yes, tools>> Create cards>> fix takes you to Systems panel with create by axis direction.