ghylander
Marine/Ocean
- Jun 5, 2023
- 11
Hi all,
I am doing some SOL103 analysis on certain subsystems of a floating structure, and I'm exploring different approaches at representing the whole structure's added mass.
One of my approaches is to simply represent the floating structure as a rigid body, using a CONM2 element.
This way, it's easy to consider the added masses and inertias, as I simply add them to the structure's own masses and inertias.
These added masses and inertias are computed by an external software.
However, I'm trying to setup an analysis of the whole floating structure together with the subsystem I'm interested as flexible bodies, to quantify the error induced by the above simplification.
I've been reading about different methods, and first found about using DMIG and GENEL (which unless I understood incorrectly are just different ways to achieve the CONM2 approach), and from there about using MFLUID regions.
While I have found some information about MFLUID, how to define it, use it, etc, I haven't found much about what it entails, or the theory about it.
Would an MFLUID card do what I need (added mass and inertia of the floating structure based on the displaced volume)?
What are its limitations?
Any guidance is appreciated.
I am using SC Femap with NX/SC Nastran.
I am doing some SOL103 analysis on certain subsystems of a floating structure, and I'm exploring different approaches at representing the whole structure's added mass.
One of my approaches is to simply represent the floating structure as a rigid body, using a CONM2 element.
This way, it's easy to consider the added masses and inertias, as I simply add them to the structure's own masses and inertias.
These added masses and inertias are computed by an external software.
However, I'm trying to setup an analysis of the whole floating structure together with the subsystem I'm interested as flexible bodies, to quantify the error induced by the above simplification.
I've been reading about different methods, and first found about using DMIG and GENEL (which unless I understood incorrectly are just different ways to achieve the CONM2 approach), and from there about using MFLUID regions.
While I have found some information about MFLUID, how to define it, use it, etc, I haven't found much about what it entails, or the theory about it.
Would an MFLUID card do what I need (added mass and inertia of the floating structure based on the displaced volume)?
What are its limitations?
Any guidance is appreciated.
I am using SC Femap with NX/SC Nastran.
