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h = 1 in
g = 386 in/sec2 Analysis Assumptions and Modeling Notes
The node locations are arbitrarily selected. The final time of 0.11 seconds allows the mass to reach its largest
deflection. The integration time step (0.11/110 ≈ 0.001 sec) is based on ≈ 1/100 of the period (during impact),
to allow the initial step acceleration change to be followed reasonably well and to produce sufficient printout
for the theoretical comparison. At release h, the mass acceleration is 386 in/sec2. Therefore, a load step with a
small time period is used to ramp to the appropriate acceleration while maintaining essentially zero velocity.
Displacements and velocities are listed against time in POST26 and stored kinetic energy is obtained in POST1.
The model is solved using the node-to-surface CONTA175 element.
ANSYS Verification Manual . ANSYS Release 9.0 . 002114 . © SAS IP, Inc. 1–150 VM65 Results
Target ANSYS Ratio 0.07198 0.072 1.000 y displacement, in -1.0000 -0.9991 0.999 y velocity, in/sec -27.79 -27.76 0.999 time,sec 0.10037 0.10100 1.006 max. y displacement, in -1.5506 -1.5503 1.000 CONTA175 At Impact time,sec At "Zero&...
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- Spring '09
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