Wrong Mode shapes??
Wrong Mode shapes??
(OP)
I did a modal analysis of a cabinet,its a big cabinet 72" tall,30" wide and 35" deep. Its an electrical cabinet with various electrical components in it. When I ran my modal analysis I am seeing my modes in components and not the entire assembly?The first freq is around 9Hz.I dont see how the whole assembly would deform ..like deformation from front to back or side to side..but i see maximum deformation in some structural components inside the cabinet instead of the whole unit.Can that be a concern? Static structural doesnt show stresses higher than yield stress.





RE: Wrong Mode shapes??
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RE: Wrong Mode shapes??
RE: Wrong Mode shapes??
Could you also have the wrong material properties for the cabinet itself? Could it be too stiff in your model?
Steve
RE: Wrong Mode shapes??
RE: Wrong Mode shapes??
Are you able to go through the modal results and find the first mode that pertains to the cabinet as a whole? I know that in past analyses of my own sometimes you have to wade through some of the low freqency mode shapes that pertain to non-critical components.
Also, with respect to the door, is the first mode shape that you are seeing a displacement normal to the front surface of the door? Reason being, is that if the door is just a simple sheetmetal door with folded edges and hinges I would expect a low freqency mode with a shape that resembles a deflection at the center of the door. Basically, this mode would be expected to be at a low freqnecy and I would be more concerned with the mode shape and freqency associated with displacments of the overal cabinet structure.