Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
How to model compression?
Posted May 23, 2011, 4:41 p.m. EDT Structural Mechanics 3 Replies
Please login with a confirmed email address before reporting spam
Hi All,
The set up for the model is a thin wire entering a block of material. The wire is already inserted to a certain depth. I am trying to determine if a compressive force is applied to the top of the wire, at what depth the wire will no longer buckle. I keep getting an error when trying to run the Study which says: The mass matrix is zero. I am a novice with COMSOL and looking for any sort of suggestions or advice.
The COMSOL parameters are currently using a Solid Mechanics platform with a point load defined and a linear buckling step. The mesh was only applied to the wire.
Any suggestions?
Thank you!
Amanda
The set up for the model is a thin wire entering a block of material. The wire is already inserted to a certain depth. I am trying to determine if a compressive force is applied to the top of the wire, at what depth the wire will no longer buckle. I keep getting an error when trying to run the Study which says: The mass matrix is zero. I am a novice with COMSOL and looking for any sort of suggestions or advice.
The COMSOL parameters are currently using a Solid Mechanics platform with a point load defined and a linear buckling step. The mesh was only applied to the wire.
Any suggestions?
Thank you!
Amanda
3 Replies Last Post May 25, 2011, 10:55 a.m. EDT
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
a mass matrix = 0 is for em a poorly defined model, you are missing something in the BCs to correctly define our PDE such that you have an unique solution
For me the easiest with buckling is to use the security factor you get from a eigenfrequency buckling analysis, in your case you must probably parametrise it to see how the bucking factor changes with the penetration depth, from what I understand
--
Good luck
Ivar
a mass matrix = 0 is for em a poorly defined model, you are missing something in the BCs to correctly define our PDE such that you have an unique solution
For me the easiest with buckling is to use the security factor you get from a eigenfrequency buckling analysis, in your case you must probably parametrise it to see how the bucking factor changes with the penetration depth, from what I understand
--
Good luck
Ivar
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Thank you for your response! In all honesty, I have not worked with COMSOL before and am having difficulty in finding resources to learn how to use it. Do you have any suggestions for learning how to model using linear buckling?
Thank you!!
Amanda
Thank you!!
Amanda
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
in general I would advise to take the video courses, look at a few of the web casts (see tha main web site), and then read the books, a couple of times.
Main advice start simple one physics at the time, and one step at the time, you will soon become an expert ;)
--
Good luck
Ivar
in general I would advise to take the video courses, look at a few of the web casts (see tha main web site), and then read the books, a couple of times.
Main advice start simple one physics at the time, and one step at the time, you will soon become an expert ;)
--
Good luck
Ivar