Ansys Learning Forum Forums Discuss Simulation LS Dyna Rock drilling Reply To: Rock drilling

javat33489
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Thank you for your responses. They were very helpful.

>>and the segment set of the drill surfaces as SURFB.

Decrease the bucket sort frequency to 1. Set BSORT=1

This helped me when solving with SPH particles

>> Change the SOFT option. Try SOFT=1 (best for SPG).

Yes, for SPG and SPH I use SOFT=1.

>> SPG is a particle method; there is no negative volume. Set ERODE=0 on *CONTROL_TIMESTEP to get rid of those messages. 

Yes, of course I use it this way, but negative volume warnings still appear.

>> You need a TIED contact between the SPG particles and the ring.

Yes, of course I do that. I redefined the contact again and everything worked.

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What I got:

SPG. At low feed speeds, the SPG drill works fine

If I increase the feed speed to 40 m/s, the SPG particles scatter and pull the seal ring with them, which is greatly distorted

 

SPH.

At low speeds, SPH particles also work normally, but fly away a lot.

When the feed speed increases to 40 m/s, the particles fly away and pull the solid ring behind them and greatly distort it

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Then I decided to remove the ring and increase the radius of the particle (SPH) circle

The particles fly away monstrously. It happens like this. The drill pierces the particles and goes far down, and the particles begin to fly for the rest of the time until almost all of them fly away. In addition, the stress are very low.

I have not yet conducted such an experiment for the SPG.

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So, I have a new problem, I hope this is the last. Particles fly away a lot. I will be waiting for your help, thank you.