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simulation fem trees

  • Thread starter Thread starter gio_deere
  • Start date Start date

gio_deere

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Hello everyone,
Excuse me if I write after a long time, but I was busy with the last (hopefully?) exam. as I had already mentioned in the following tread, I'm continuing my thesis work on a reducer. Now I'm focusing on static tree simulation. After I was informed and see how to set constraints and forces, I put myself to work. the trees to simulate are 3, respectively an input tree, one of reference and one of exit. for the application of forces I have based on static patterns of beams (hand solved of which I attach drawings and calculations [Estratto 2]). Based only on the forces of reaction to the constraints (I used the bearing bond) I find myself only with the first two trees. in the output shaft, problems are encountered, perhaps linked to the definition of the forces (it does not correctly execute the simulation and goes in error) . regarding the stresses, the problem of understanding with which data to compare them. I also allego the fatigue test of the trees [Estratto 3].
what I ask is to direct or advise me if I am going on the right path.
if it can be useful I explain briefly how I set forces and constraints:
1) I used the division line command to locate the portions of the shaft that will accommodate the bearings and wheels
2) with regard to the forces, I applied the result of perhaps radial and tangential vertically, the axial forces along the axis, while where there was an eccentric bending moment, I applied a torque compared to a perpendicular axis of the tree, trying to simulate the pure moment (because in solidworks there is no specific command)

if you need to explain something else do not hesitate to ask me. I thank all those who will help me in advance?
(I attach extracts and screens)
 

Attachments

  • Estratto 2.pdf
    Estratto 2.pdf
    1.6 MB · Views: 29
  • Estratto 3.pdf
    Estratto 3.pdf
    1 MB · Views: 17
  • Annotazione 2020-09-07 172912.webp
    Annotazione 2020-09-07 172912.webp
    78 KB · Views: 42
  • Annotazione 2020-09-07 173017.webp
    Annotazione 2020-09-07 173017.webp
    50.4 KB · Views: 39
  • Annotazione 2020-09-07 173254.webp
    Annotazione 2020-09-07 173254.webp
    74.2 KB · Views: 28
  • Annotazione 2020-09-07 173422.webp
    Annotazione 2020-09-07 173422.webp
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Good evening to all,
Excuse me if I seem insistent. I would like at least to clarify my doubt, that is, it is correct that it submits the tree to only radial, tangential and axial forces or should I start the simulation with the only pairs agents on the tree?
or, again, do I have to test the complete shaft of toothed wheels? (although the computational view seems to me heavy meshare even the dense wheels)
If anyone can help me, I'd be really grateful.
 
If you do tree analysis you have to do so to apply all forces, couples and transport moments on the tree.
solidworks gives you the opportunity to do the remote loads.....see qui.
does not need meshare gears and bearings to evaluate the shaft.
to me personally the bearing constraints managed by solidworks do not like and for this use advanced constraints and I put way, direction and reaction components. . ..just like in all the fems a little rougher.
 
thanks for the answer,
I used the bearing constraints, but without ticking the adjustable bearing option, I also considered bearings with "infinite" stiffness.
I've never used remote loads, could I be useful to apply the flenching moment or better still the eccentric axial force (due to the conical wheels) in case how should I behave?

Thank you again for all the support!
 
thanks for the answer,
I used the bearing constraints, but without ticking the adjustable bearing option, I also considered bearings with "infinite" stiffness.
I've never used remote loads, could I be useful to apply the flenching moment or better still the eccentric axial force (due to the conical wheels) in case how should I behave?

Thank you again for all the support!
don't give me your favor.... .
all that is not applicable directly on the tree, must be done remotely. If I have a gear I have two or three components... which are forces and it would be better to put them on the primitive diameter and not who knows where.
 
don't give me your favor.... .
all that is not applicable directly on the tree, must be done remotely. If I have a gear I have two or three components... which are forces and it would be better to put them on the primitive diameter and not who knows where.
Yes, excuse me, the habit of writing mail to the various professors leads me to this.
ok, I understood, therefore I imposed the couple to which the tree is subjected directly on the tree, while the various forces that exchange the wheels (radial, tangential and axial) the sticks as remote loads.
I will try so, as soon as I have the PC available again. (Do machinery always break when you need it?)

Thank you again!
 

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