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Coupling three physics "variables not solved for"
Posted Feb 26, 2013, 1:35 p.m. EST Modeling Tools & Definitions, Parameters, Variables, & Functions, Studies & Solvers Version 4.3 1 Reply
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Hi,
I have to solve three different physics together in COMSOL .
physics 1-Electrostatics: solving for variable V
physics 2-Electrostatics:solving for variable V2
physics 3-Navier stokes equation:solves for u and p(body force term is rho1*Ez2 where rho1 is charge density obtained from physics1 and Ez2 is electric field obtained from physics2)
The structure of the problem :At each time step,physics 1 and physics 2 are independent to each other (no relation between them) but physics 3 uses the results of physics 1&2.I have to solve them with time dependent solver.
To reduce computational effort and to have individual mesh for each physics,I want to solve physics 1(V) and store data (say data1) ,physics 2 (V2) and store data (say data2)and followed by physics 3.Is there any way in comsol 3.3 to 4.3 versions to do this?As I have seen in comsol latest versions,we have option "dependent variables not solved for " but there we cannot select two stored solutions simultaneously.For now I have solved physics 1 & physics 2 together and stored as data 1 and given this as input to physics 3 through option " variables not solved for"
Summarizing I need to know "How to transfer solution from two independent studies or two independent study steps to third study or third study step at each time step"?
Regards
Bhavanarayana chakka
I have to solve three different physics together in COMSOL .
physics 1-Electrostatics: solving for variable V
physics 2-Electrostatics:solving for variable V2
physics 3-Navier stokes equation:solves for u and p(body force term is rho1*Ez2 where rho1 is charge density obtained from physics1 and Ez2 is electric field obtained from physics2)
The structure of the problem :At each time step,physics 1 and physics 2 are independent to each other (no relation between them) but physics 3 uses the results of physics 1&2.I have to solve them with time dependent solver.
To reduce computational effort and to have individual mesh for each physics,I want to solve physics 1(V) and store data (say data1) ,physics 2 (V2) and store data (say data2)and followed by physics 3.Is there any way in comsol 3.3 to 4.3 versions to do this?As I have seen in comsol latest versions,we have option "dependent variables not solved for " but there we cannot select two stored solutions simultaneously.For now I have solved physics 1 & physics 2 together and stored as data 1 and given this as input to physics 3 through option " variables not solved for"
Summarizing I need to know "How to transfer solution from two independent studies or two independent study steps to third study or third study step at each time step"?
Regards
Bhavanarayana chakka
1 Reply Last Post Feb 27, 2013, 2:23 a.m. EST
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Posted:
1 decade ago
Hi
you could probably "Join" two data sets (v4.3a), and see if you can extract the variables from therein
Interesting point: read initial data from several studies
--
Good luck
Ivar
you could probably "Join" two data sets (v4.3a), and see if you can extract the variables from therein
Interesting point: read initial data from several studies
--
Good luck
Ivar