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Ansys Learning Forum › Forums › Discuss Simulation › General Mechanical › Falling under the force of gravity into a transient › Reply To: Falling under the force of gravity into a transient

March 1, 2023 at 1:02 am
peteroznewman
Subscriber

Hello Javat,

If the part is in free fall, meaning that the only force acting on the part is gravity, the correct way to model this is to calculate the impact velocity from the distance of the fall, and assemble the parts so that the falling part is positioned at the point of contact. The falling part is given the Initial Condition of a downward velocity equal to the impact velocity. That means that at time=0, the contact is already closed and ready to begin decelerating the part.

Calculating the impact velocity from the drop height is a simple physics equation, or you can use an online calculator.

You still have to turn on Auto Time Stepping and make the Initial Time Step a small number like 1e-4 s, the Minimum Time Step 1e-6 s and the Maximum Time Step 1e-3 s.