contact slip analysis
Hello,
I want to find the torque required for the slip of the interference fit.
Could someone help me how can I do it.
If Could you please provide me any short sample opristruct deck (.fem file) or explain detail will help me.
I saw some of the posts earlier, but could not understand fully.
Thanks and I appriciate your help in advance !!
THanks for the help.
Looking forward for your reply.
Best Answer
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Sid_22073 said:
Hello,
I have run 2 cases with SLIDING and with friction 0.12 between the pairs.
Please see the results below of the reaction moments about X axis.
The curves are pretty straight, I would rather expect a quadratic curve i.e increase in torque and after some time the torque decreases
Is my problem setup correct ?
Please note I applied SPCD of 6.28319 radian ie 360 degrees
can somebody help to resolve this if not correct ?
I did this small model here.
I got a decrease in the torque after some rotation.
I have 2 loadcases:
- press-fit
- rotation continuing from LC1
on the right corner in the bottom you will see torque x rotation
1
Altair EmployeeAnswers
-
could you add a few more details on what are you trying to accomploish, and maybe add some pictures?
If you want one part to be iserted into another, you will need a LGDISP contact with Continuous or Finite Sliding at least.
But with so few details it is hard to give you more insights.
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The pin (middle part) is assembled by an interference fit.
I want to now check how much torque this pin can withstand before slipping. For this want to apply torque at both ends of pin along the axis and somehow get the reaction forces and plot this in graph. I would like to see a no-linear curve ( timestep vs reaction force)
Please check the following .fem file and let me know if run correct.
First subcase is for contact
2nd subcase is for contact + moment
$$ optistruct
$
CONTF(H3D,PCONT) = YES
CSTRESS(H3D,ALL,NDIV=1) = ALL
DISPLACEMENT(H3D) = ALL
GPSTRESS(H3D) = ALL
SPCFORCE(H3D) = 5
STRESS(H3D) = YES
$$------------------------------------------------------------------------------$
$$ Case Control Cards $
$$------------------------------------------------------------------------------$
$
$HMNAME LOADSTEP 1"loadstep1" 9
$
SUBCASE 1
LABEL loadstep1
ANALYSIS NLSTAT
SPC = 1
NLPARM = 1
$
$HMNAME LOADSTEP 2"loadstep2" 9
$
SUBCASE 2
LABEL loadstep2
ANALYSIS NLSTAT
CNTNLSUB YES
SPC = 1
LOAD = 9
NLPARM = 1
NLOUT = 4
$$--------------------------------------------------------------
$$ HYPERMESH TAGS
$$--------------------------------------------------------------
$$BEGIN TAGS
$$END TAGS
$
BEGIN BULK
$$
$$ Stacking Information for Ply-Based Composite Definition
$$
$
$HMSET 5 1 "set1" 18
$HMSETTYPE 5 "non-ordered" 18
SET 5 GRID LIST
+ 2158833 2158834...
..
..
..
$$$$ Contact definition
$HMNAME GROUP 1"CSurf_pin_CSurf_gear_fuelpumpside" "CONTACT"
$HWCOLOR GROUP 1 48
$$
$$ CONTACT Data
$$
CONTACT 1 SLIDE 1 2 -0.037
+ CONSLI
$
$$
$HMNAME GROUP 2"CSurf_Gear_outputside_CSurf_pin_1" "CONTACT"
$HWCOLOR GROUP 2 49
CONTACT 2 SLIDE 3 4 -0.037
+ CONSLI
$..
..
..
$$
$$ Nonlinear Parameters
$$
$
$HMNAME LOADSTEPINPUT 1"nlparrm"
NLPARM 1 10 0.0 25
$
$$
$$ Output Parameters
$$
$
$HMNAME LOADSTEPINPUT 4"loadstepinput4"
NLOUT 4NINT 10..
..
..
$$ Global SPC Data
SPC 1 212226 123456 0.0
SPC 1 212227 123456 0.0$$ Also SPC Data ends of Pin ( Blue part)
SPC 1 2158834 123456 0.0
SPC 1 2158833 123456 0.0
$$
$$ SPCD Data
$$
SPCD 9 2158834 4 6.28319
SPCD 9 2158833 4 6.28319
ENDDATA0 -
Hello,
I have run 2 cases with SLIDING and with friction 0.12 between the pairs.
Please see the results below of the reaction moments about X axis.
The curves are pretty straight, I would rather expect a quadratic curve i.e increase in torque and after some time the torque decreases
Is my problem setup correct ?
Please note I applied SPCD of 6.28319 radian ie 360 degrees
can somebody help to resolve this if not correct ?
0 -
Sid_22073 said:
Hello,
I have run 2 cases with SLIDING and with friction 0.12 between the pairs.
Please see the results below of the reaction moments about X axis.
The curves are pretty straight, I would rather expect a quadratic curve i.e increase in torque and after some time the torque decreases
Is my problem setup correct ?
Please note I applied SPCD of 6.28319 radian ie 360 degrees
can somebody help to resolve this if not correct ?
I did this small model here.
I got a decrease in the torque after some rotation.
I have 2 loadcases:
- press-fit
- rotation continuing from LC1
on the right corner in the bottom you will see torque x rotation
1 -
Hi,
Thanks for the answer.
Is the SPCD i.e enforced rotation given to both ends of the shaft ?
Did you use friction ?
If possible Can you please share the model ?
Kind regards,
SId
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Sid_22073 said:
Hi,
Thanks for the answer.
Is the SPCD i.e enforced rotation given to both ends of the shaft ?
Did you use friction ?
If possible Can you please share the model ?
Kind regards,
SId
the model was there in my reply.
I've used SPC directly to impose rotation to one end only, attached to the RBE2.
I've used friction, otherwise there would be no decrease in torque, right?
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Adriano A. Koga_21884 said:
the model was there in my reply.
I've used SPC directly to impose rotation to one end only, attached to the RBE2.
I've used friction, otherwise there would be no decrease in torque, right?
i would add CONTF output in order to check the change in contact status, from stick to slip, when slippage starts to occur.
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Thank you very much !!
0