I am having a problem with running a static analysis on a tube frame I created in Solidworks.
This is my first time using Cosmos, in the past I have used MSC.Nastran & Patran with excellent results. I am not sure if I am having problems with the model, the mesh, or something else.
I built the tube frame from Solid extrusions and sweeps, all members are thin walled, most are .065 wall thickness, the hoops are .095, and it is merged as one solidbody.
I then setup a study for cosmos using shells from surface, .5in elements with .1 tolerance. I run the mesh and it runs fine. I then flip the shells to make sure all of the exposed faces are the front. Then I click on run. After app. 45 secs of elapsed time I get an error message "Jacobean contains a negative element, continue?" I click yes and then get another message about a Jacobean element (can't remember right now what it said), and finally I get a message about an element radius/thickness ratio being app. .235 and the run stops. Then a box pops up saying analysis failed.
Is this a problem with the mesh or the frame (or both)? The frame contains many small edges due to the sweeps and extrusions meeting up, but it is all one solid part and the geometry check verifys. Do I need to use a finer element size and a higher tolerance? I'm just worried because in Patran when you use to high of a tolerance it would collapse some elements and change the geometry.
Thank you in advance.
This is my first time using Cosmos, in the past I have used MSC.Nastran & Patran with excellent results. I am not sure if I am having problems with the model, the mesh, or something else.
I built the tube frame from Solid extrusions and sweeps, all members are thin walled, most are .065 wall thickness, the hoops are .095, and it is merged as one solidbody.
I then setup a study for cosmos using shells from surface, .5in elements with .1 tolerance. I run the mesh and it runs fine. I then flip the shells to make sure all of the exposed faces are the front. Then I click on run. After app. 45 secs of elapsed time I get an error message "Jacobean contains a negative element, continue?" I click yes and then get another message about a Jacobean element (can't remember right now what it said), and finally I get a message about an element radius/thickness ratio being app. .235 and the run stops. Then a box pops up saying analysis failed.
Is this a problem with the mesh or the frame (or both)? The frame contains many small edges due to the sweeps and extrusions meeting up, but it is all one solid part and the geometry check verifys. Do I need to use a finer element size and a higher tolerance? I'm just worried because in Patran when you use to high of a tolerance it would collapse some elements and change the geometry.
Thank you in advance.