AnsweredAssumed Answered

The result I got using symmetry condition is not the same as the one i got using entire model.

Question asked by Will Kim on Sep 12, 2016
Latest reply on Sep 13, 2016 by Mark Stowart

Hello, brilliant minds:)
I am analyzing the effects of loads on the truss support of conveyor system with particular interest on resulting deflection (both magnitude and the location)


entire model.JPG

As shown above, I removed some parts and added remote loads instead. And there you go, I got the result like that. Note that the one truss is an exact image of the other.


In an effort to verify my simulation result, I ran the same analysis using one truss as shown below. My assumption is that each truss would receive exact half of the total load because those four load points are occurring at the exact middle points between two trusses. So I applied to the exact locations half the load that was applied in previous example. (5880 ->2940N) Also, the direction of force is also the same.


only one truss.JPG


what is driving me crazy is that the resulting displacement plot is vastly differently from the one i got when two truss stands. Further, Stress plots are similar but with exaggerated magnitudes (50%higher roughly) on one truss analysis. Because I got two different results, I cannot verify that my obtained result is correct. Anybody knows what is wrong here?


Note that in one truss model, I excluded parts that are not to be analyzed in the simulation stage not in the modelling stage. That is why you see that center of mass indication standing beside the truss. Also, mesh conditions, boundary conditions, contact conditions are the same.


Thank you!