Altair RISE

A program to recognize and reward our most engaged community members

Nominate Yourself Now!

External Forces Work

Subhu_21017

HI All,

I am running a crash analysis.

I have no external force applied to my model except initial velocity and gravity.

the model is set to impact on a rigidwall

Will the External Forces Work remains constant or increase or decrease??

THANKS in Advance

Regards,

SUBHU

Find more posts tagged with

English

Radioss

Accepted answers

All comments

Subhu_21017

The External Work Forces is Decreasing. Is this Good??

<?xml version="1.0" encoding="UTF-8"?>

Altair Forum User

Hi Subhu,

External work is any external loading applied in the simulation. This can include, Imposed movement (displacement, velocity or acceleration), force (/CLOAD or /GRAV), and pressure to name a few. Work by done an external force on a system is always a transfer of energy to some other form of energy and this negative work represents the transfer of energy during the simulation and this is fine.

jsk459

Hi,

Please let me know below mentioned energy relations are correct or not.

External work = Internal energy+kinetic energy+contact energy+hourglass energy

Total energy = Internal energy + kinetic energy

Nachiket Kadu_22143

Hi,

Please let me know below mentioned energy relations are correct or not.

External work = Internal energy+kinetic energy+contact energy+hourglass energy

Total energy = Internal energy + kinetic energy

@jsk459 Yes the above relation is correct.

Andy_20955

External work = Internal energy+kinetic energy+contact energy+hourglass energy

This is NOT correct.

External Work includes the work from Imposed movement (displacement, velocity or acceleration), force (/CLOAD or /GRAV), and pressure. It also include the frictional energy from a /RWALL (when FRIC!=0.0)

If there are only an initial velocity, gravity and a rigid wall in the model then I would assume the high negative external work is caused by the friction on the rigid wall and maybe gravity. It is difficult to say without seeing the model.

Thank,

Andy