Reach p from fvmotionsolver

January 9, 2009, 07:16

Dear Foamers,
I'm trying add to the displacementLaplacianFvMotionSolver a calculation of the pressure forces which i later like to add to the as motion on the mesh. Due to my poor knowledge in C++ i can not find a way to extract the p-field. i have been looking at the objectregistry, but how to implement this?
i would be thankful for your help
Erik

philippose · January 9, 2009, 07:26

Hello Erik,

A good day to you :-)!

For a starter on what you are trying to do, go to the search function of this discussion board, and look for "simpleForceFoam"....

The first result you get will take you to a thread which I had started quite some time ago, when I was implementing exactly what you are trying...

There are versions of the solver I wrote available for download on the thread too....

I am sure you will get most of what you want there.

Have a nice day!

Philippose

January 9, 2009, 08:36

my bad, tha last one should work do get the field, and it is for me right now.
however i'm still very interested in the answer to the question on where (if it matters) to put the mesh motion.
thank you
Erik

lillberg · January 9, 2009, 08:43

Hi Erik, Eric here ;-)

Can you explain what you need to do in terms of physics and we might be able to help you better, most meshmotion and FSI implementations has most likely already been done somewhere by someone.

BR

/Eric

January 9, 2009, 09:11

Hi Eric!
brilliant, i'll give it a shot!

what i'am looking to do is implement a 3-DOF/6-DOF solver. i have been rewriting the interDymFoam with the aid of the work that Philippose Rajan have done, and which he refered above. this has been very useful. so basicly i like to solve the ODE's for 3/6-DOF and use the OF-library to implement this. for the course i'm doing at Chalmers (Gothenburg), i like to use the septernion/quaternion classes to transform the points with. i found, when working in the solver that i ran into problems with the gamma and the interface, it crashed.
now i think i have reached a point where i have at least to just calculated the forces and then apply this to the mesh, but maybe you can forecast problem which i can not see right now.
thank you for your help!
Erik

lillberg · January 9, 2009, 10:25

Have you had a look at the 6-dof implementation in the dev version by Hrv.

/E

January 9, 2009, 10:30

nope, is it possible to find this online?
it would be most interesting!
Erik

philippose · January 9, 2009, 10:46

Hello again Erik,

I was going to inform you about the 6-dof solver present in the dev version too :-)!

Basically, The 1.5-dev version has a library for 6-dof motion which works with quaternions, along with a couple of examples (present in the tutorials folder).

This version can be found at the following link:

http://powerlab.fsb.hr/ped/kturbo/OpenFOAM/release/

A pre-compiled version is not yet available, so you will have to compile it yourself.

Have a nice day!

Philippose

January 9, 2009, 11:06

no worries

thank you for your help!

i will try to compile this as soon as i get on my own computer, in any case i should be able to get some good ideas!

brilliant!
same to you, and a good WE!

Erik

lillberg · January 11, 2009, 17:13

Hi Erik,

Have a look at the SDA and SKA solidBodyMotionFunctions in the standard 1.5.x version, ~/OpenFOAM/OpenFOAM-1.5.x/src/dynamicFvMesh/solidBodyMotionFvMesh

/Eric

January 9, 2009, 07:16	Dear Foamers, I'm trying add	#1
erik023 Guest Posts: n/a	Dear Foamers, I'm trying add to the displacementLaplacianFvMotionSolver a calculation of the pressure forces which i later like to add to the as motion on the mesh. Due to my poor knowledge in C++ i can not find a way to extract the p-field. i have been looking at the objectregistry, but how to implement this? i would be thankful for your help Erik

January 9, 2009, 07:26	Hello Erik, A good day to y	#2
philippose Senior Member Philippose Rajan Join Date: Mar 2009 Location: Germany Posts: 552 Rep Power: 25	Hello Erik, A good day to you :-)! For a starter on what you are trying to do, go to the search function of this discussion board, and look for "simpleForceFoam".... The first result you get will take you to a thread which I had started quite some time ago, when I was implementing exactly what you are trying... There are versions of the solver I wrote available for download on the thread too.... I am sure you will get most of what you want there. Have a nice day! Philippose

January 9, 2009, 08:36	my bad, tha last one should wo	#3
erik023 Guest Posts: n/a	my bad, tha last one should work do get the field, and it is for me right now. however i'm still very interested in the answer to the question on where (if it matters) to put the mesh motion. thank you Erik

January 9, 2009, 08:43	Hi Erik, Eric here ;-) Can	#4
lillberg Member Eric Lillberg Join Date: Mar 2009 Location: Stockholm Posts: 80 Rep Power: 17	Hi Erik, Eric here ;-) Can you explain what you need to do in terms of physics and we might be able to help you better, most meshmotion and FSI implementations has most likely already been done somewhere by someone. BR /Eric

January 9, 2009, 09:11	Hi Eric! brilliant, i'll give	#5
erik023 Guest Posts: n/a	Hi Eric! brilliant, i'll give it a shot! what i'am looking to do is implement a 3-DOF/6-DOF solver. i have been rewriting the interDymFoam with the aid of the work that Philippose Rajan have done, and which he refered above. this has been very useful. so basicly i like to solve the ODE's for 3/6-DOF and use the OF-library to implement this. for the course i'm doing at Chalmers (Gothenburg), i like to use the septernion/quaternion classes to transform the points with. i found, when working in the solver that i ran into problems with the gamma and the interface, it crashed. now i think i have reached a point where i have at least to just calculated the forces and then apply this to the mesh, but maybe you can forecast problem which i can not see right now. thank you for your help! Erik

January 9, 2009, 10:25	Have you had a look at the 6-d	#6
lillberg Member Eric Lillberg Join Date: Mar 2009 Location: Stockholm Posts: 80 Rep Power: 17	Have you had a look at the 6-dof implementation in the dev version by Hrv. /E

January 9, 2009, 10:30	nope, is it possible to find t	#7
erik023 Guest Posts: n/a	nope, is it possible to find this online? it would be most interesting! Erik

January 9, 2009, 10:46	Hello again Erik, I was goi	#8
philippose Senior Member Philippose Rajan Join Date: Mar 2009 Location: Germany Posts: 552 Rep Power: 25	Hello again Erik, I was going to inform you about the 6-dof solver present in the dev version too :-)! Basically, The 1.5-dev version has a library for 6-dof motion which works with quaternions, along with a couple of examples (present in the tutorials folder). This version can be found at the following link: http://powerlab.fsb.hr/ped/kturbo/OpenFOAM/release/ A pre-compiled version is not yet available, so you will have to compile it yourself. Have a nice day! Philippose

January 9, 2009, 11:06	no worries http://www.cfd-onli	#9
erik023 Guest Posts: n/a	no worries thank you for your help! i will try to compile this as soon as i get on my own computer, in any case i should be able to get some good ideas! brilliant! same to you, and a good WE! Erik

January 11, 2009, 17:13	Hi Erik, Have a look at the	#10
lillberg Member Eric Lillberg Join Date: Mar 2009 Location: Stockholm Posts: 80 Rep Power: 17	Hi Erik, Have a look at the SDA and SKA solidBodyMotionFunctions in the standard 1.5.x version, ~/OpenFOAM/OpenFOAM-1.5.x/src/dynamicFvMesh/solidBodyMotionFvMesh /Eric

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