how to add spring/damping effect to connect two moving body

Teemo · March 27, 2013, 10:47

Dear FoAMers,

I would like to connect these two moving parts together by a spring , how can I achieve it in OPENFOAM?

Your suggestion will be appreciated.

Regards,
T

Teemo · March 27, 2013, 10:50

ngj · March 27, 2013, 12:17

Hi Teemo,

I my version of OF (1.6-ext) you can find the following constraints for mesh motion here:

Code:

/src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionRestraint

The linear spring seems like a good choice for the initial investigation.

I have no idea on how they are working, though I know that the are also present in the more recent releases of OF.

Good luck,

Niels

Teemo · March 27, 2013, 12:41

Thanks Niels,

I will give it a try.

Regards,
T

Teemo · March 27, 2013, 13:23

hello again,

I have looked into the linear spring file and for its setup:
//- Anchor point, where the spring is attached to an immovable object
point anchor_;

//- Reference point of attachment to the solid body
point refAttachmentPt_;

//- Spring stiffness coefficient (N/m)
scalar stiffness_;

//- Damping coefficient (Ns/m)
scalar damping_;

//- Rest length - length of spring when no forces are applied to it
scalar restLength_;
it seems that one end of the spring should be fixed, but for my case, i need both ends move with the floaters, any idea?

Regards,
T

tyoung · November 10, 2014, 11:09

Hi Teemo,

I am currently facing similar situation and would like to know whether you had any luck on it?

Regards
tyoung

March 27, 2013, 10:47	how to add spring/damping effect to connect two moving body	#1
Teemo New Member Teemo Join Date: May 2012 Posts: 28 Rep Power: 14	Dear FoAMers, I would like to connect these two moving parts together by a spring , how can I achieve it in OPENFOAM? Your suggestion will be appreciated. Regards, T

March 27, 2013, 10:50		#2
Teemo New Member Teemo Join Date: May 2012 Posts: 28 Rep Power: 14	Last edited by Teemo; March 27, 2013 at 11:13.

March 27, 2013, 12:17		#3
ngj Senior Member Niels Gjoel Jacobsen Join Date: Mar 2009 Location: Copenhagen, Denmark Posts: 1,903 Rep Power: 37	Hi Teemo, I my version of OF (1.6-ext) you can find the following constraints for mesh motion here: Code: /src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionRestraint The linear spring seems like a good choice for the initial investigation. I have no idea on how they are working, though I know that the are also present in the more recent releases of OF. Good luck, Niels

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March 27, 2013, 12:41		#4
Teemo New Member Teemo Join Date: May 2012 Posts: 28 Rep Power: 14	Thanks Niels, I will give it a try. Regards, T

March 27, 2013, 13:23		#5
Teemo New Member Teemo Join Date: May 2012 Posts: 28 Rep Power: 14	hello again, I have looked into the linear spring file and for its setup: //- Anchor point, where the spring is attached to an immovable object point anchor_; //- Reference point of attachment to the solid body point refAttachmentPt_; //- Spring stiffness coefficient (N/m) scalar stiffness_; //- Damping coefficient (Ns/m) scalar damping_; //- Rest length - length of spring when no forces are applied to it scalar restLength_; it seems that one end of the spring should be fixed, but for my case, i need both ends move with the floaters, any idea? Regards, T

November 10, 2014, 11:09		#6
tyoung New Member Teng Join Date: May 2011 Location: UK Posts: 5 Rep Power: 15	Hi Teemo, I am currently facing similar situation and would like to know whether you had any luck on it? Regards tyoung