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Prescribed mesh velocity
Posted Feb 1, 2012, 3:35 a.m. EST Mesh Version 4.2a 2 Replies
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Hi everyone,
in a prescribed mesh velocity, if i want that a boundary has a free prescribed mesh velocity in x direction i have two options:
vx no write nothing
or
√ vx u
if i change the coordinate system, how can i to do the same?
One way will be
vt no write nothing
but the other?
√ vt ??????
Thanks you
JL
in a prescribed mesh velocity, if i want that a boundary has a free prescribed mesh velocity in x direction i have two options:
vx no write nothing
or
√ vx u
if i change the coordinate system, how can i to do the same?
One way will be
vt no write nothing
but the other?
√ vt ??????
Thanks you
JL
2 Replies Last Post Feb 1, 2012, 8:21 a.m. EST
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Posted:
1 decade ago
Hi
I'm not 100% sure I catch you.
A prescribed displacement or velocity unchecked = free motion no restritions
If checked = 0 the mesh is fixed, if = u (u or u_solid from solid, it's a displacement) then the mesh is driven by the other physics.
If its = u (u or u_fluid from CFD) it's a velocity.
U remains along the coordinate direction x so you need to redefine your variables to project them into the global coordinate system. this can be done via a coordinate system i.e. sys2.r ... or its inverse see coordinate in the doc
--
Good luck
Ivar
I'm not 100% sure I catch you.
A prescribed displacement or velocity unchecked = free motion no restritions
If checked = 0 the mesh is fixed, if = u (u or u_solid from solid, it's a displacement) then the mesh is driven by the other physics.
If its = u (u or u_fluid from CFD) it's a velocity.
U remains along the coordinate direction x so you need to redefine your variables to project them into the global coordinate system. this can be done via a coordinate system i.e. sys2.r ... or its inverse see coordinate in the doc
--
Good luck
Ivar
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Posted:
1 decade ago
Hi Ivar,
you are helping a lot in the conplicated model that i am developing.
I will reformulate by question:
i have 2 physics: lanimar flow and moving mesh. The gravity force deform the drop.
in one boundary i have inplemented prescribed mesh velocity. I have change the coordinate system from global coordinate system to boundary system 1. So, i have to write the velocity for tangential and normal direction.
In case of normal velocity (from a distance of 30e-3 has velocity and after no)
(u*nr+w*nz)*(R>30e-3)+0)*(R=<30e-3)
I have doubt in case of tangential velocity. I want to be it free motion until (R>30e-3). After, 0.
Any idea?
Thanks
JL
you are helping a lot in the conplicated model that i am developing.
I will reformulate by question:
i have 2 physics: lanimar flow and moving mesh. The gravity force deform the drop.
in one boundary i have inplemented prescribed mesh velocity. I have change the coordinate system from global coordinate system to boundary system 1. So, i have to write the velocity for tangential and normal direction.
In case of normal velocity (from a distance of 30e-3 has velocity and after no)
(u*nr+w*nz)*(R>30e-3)+0)*(R=<30e-3)
I have doubt in case of tangential velocity. I want to be it free motion until (R>30e-3). After, 0.
Any idea?
Thanks
JL