So...how much do you guys trust Cosmos express?
So...how much do you guys trust Cosmos express?
(OP)
I just did an analysis on a simplified representation of a thiung we build at work. I constrained it and loaded it pretty much how it will live its life.
Now I'm no stress guy by any means.... but I guess I was a little surprised by the results. I thought the stresses would be higher than they seem to be. I guess this is good news, but I wonder if I'm being lulled into a false sense of security?
Now I'm no stress guy by any means.... but I guess I was a little surprised by the results. I thought the stresses would be higher than they seem to be. I guess this is good news, but I wonder if I'm being lulled into a false sense of security?






RE: So...how much do you guys trust Cosmos express?
RE: So...how much do you guys trust Cosmos express?
Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP1.1 / PDMWorks 05
ctopher's home site
RE: So...how much do you guys trust Cosmos express?
Making the best use of this Forum. FAQ559-716
How to get answers to your SW questions. FAQ559-1091
Helpful SW websites every user should be aware of. FAQ559-520
RE: So...how much do you guys trust Cosmos express?
Best Regards,
Heckler
Do you trust your intuition or go with the flow?
RE: So...how much do you guys trust Cosmos express?
RE: So...how much do you guys trust Cosmos express?
RE: So...how much do you guys trust Cosmos express?
Best Regards,
Heckler
Do you trust your intuition or go with the flow?
RE: So...how much do you guys trust Cosmos express?
I agree with Heckler "garbage in, garbage out".
Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP1.1 / PDMWorks 05
ctopher's home site
RE: So...how much do you guys trust Cosmos express?
The thing I was trying to analyze is essentially cube, 24" x 24" x 32". made of 10 ga. steel. It has two vertical chunks of 1/2" x5" x5" angle about 15" long weld on the sides as mounting brackets. (as that's what we had handy in the shop). Once filled with oil, the tank will weigh about 700 lbs.
My concern was the area where the angles are welded to the tank. Sure the angles are really strong, but could the sheet metal tear near the welds?
For my purposes, in SW I made the cube. Shelled it, and added two angles. (all as a single part of course)
I fixed the vertical mounting faces of the angles and put a 2000 lb load on the bottom face of the tank. (I realize that I'm ignoring the bolted joints, and the pressure exerted by the oil on the tank itelf.)
But anyway, I ran the analysis, and it said that I have almost no stress even remotely near the angles. All of the stress is on the bottom of the tank. Which sort of makes sense because that's where the load is being applied. But there's almost no stress in the area of my reaction force. It's essentially a cantilever. I was expecting to at least get SOMETHING around my mounting brackets.
This is why I find the results a little suspect.
Like I said, I'm no stress guy....but I'm not a COMPLETE moron....no matter what my wife may tell you.
RE: So...how much do you guys trust Cosmos express?
Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP1.1 / PDMWorks 05
ctopher's home site
RE: So...how much do you guys trust Cosmos express?
RE: So...how much do you guys trust Cosmos express?
Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP1.1 / PDMWorks 05
ctopher's home site
RE: So...how much do you guys trust Cosmos express?
sigh...I'm new...
RE: So...how much do you guys trust Cosmos express?
RE: So...how much do you guys trust Cosmos express?
Making the best use of this Forum. FAQ559-716
How to get answers to your SW questions. FAQ559-1091
Helpful SW websites every user should be aware of. FAQ559-520
RE: So...how much do you guys trust Cosmos express?
The problem is CWE's limitations on said elements, properties, loads, and constraints.
RE: So...how much do you guys trust Cosmos express?
-static analysis
-small deformations
-just one type of constraint: fully restraint
-no temperature time dependent materials (if I remember well)
-just for ELASTIC domain of deformations
-ONLY for ductile materials; the Von Mises equivalent stress apply just for this type
-no control of meshing process
-just force and pressure as input loads
In conclusion, can CosmosExpress be used for something? Remember that a lot of objects you design, fall in this category. If you need more detailed analysis you can take a step further and use CosmosWorks. If your object behaviour is more complicated (non-linear, dynamic,non-linear materials, creep, fatigue, etc), go with a good FEA program like ANSYS, ABAQUS, NASTRAN.
The tank drop analysis is a dynamic type one. Stresses can be in this case 5-10 times larger. The tank can undergo plastic deformations as well. Talk with a stress analyst to do your task (FYI,ANSYS has a drop module for this case).