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getting error with resultant forces. is my setup correct?

getting error with resultant forces. is my setup correct?

getting error with resultant forces. is my setup correct?

(OP)
Hi
I have a cutter assembly for a shredder which im trying to get the shaft loads for bearing and bending stress.
Its a 3 shaft machine and when all 3 shafts are turning there is a combination of loading happening. I can get the 3 shafts to simulate what looks like correct deflection but when i check the reaction force from one shaft to another against my hand calc the simulation values are lower than expected. So i went back to basics and simplified the simulation setup to just one shaft with torque so i could play with the fixtures and restraint to see if i was setup wrong but nothing gets close.
File attached
"shaft 4" has 2400000 lb/in driving "cutter upper 3" against "cutter stop lower 1" (just a dummy part to transfer load to shaft 1).
I calc that the force applied to "cutter stop lower 1" is torque divided by radius of "cutter upper 3" 2400000/16.25 = 147000 lbs
simulation shows 52900 lbs in expected angle.?????
I've tried splitting face on "cutter stop lower 1" and fixing it to get reaction force. tried not restraining shaft 1 and looking at free body forces but no joy.
What do you see im missing here?

RE: getting error with resultant forces. is my setup correct?

Hi Bjason.
Did you solve this problem?

If I run the model with "shaft 4", "cutter upper 3" and the 2 "shaft retainers" and add a fix geometry on the edge on the cutter that transfer the load, the resultant force on the edge is 68371 lbs.
If I run the model with only "shaft 4" and "cutter upper 3" and replace the bearing connectors with 2 "on cylindrical faces" with no radial movement, the resultant force on the edge is 149000 lbs.

Displacement on the shaft and cutter is similar in both solutions (0,107in and 0,110in)

RE: getting error with resultant forces. is my setup correct?

Hi again.
Ok, found the problem.

The first face selected for a bearing connector should be the "shaft" and the second face should be the "housing".
You did select the housing face as shaft. If you change this the result will be correct.

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