# How do i simulate this situation in catia Structural analysis?

1. Apr 11, 2014

### Webbd050

I have a rotor spinning perpendicular to the direction of travel of a car. Its supported at either end of its axle by bearings. The car crashes and ive calculated the force of the crash to be approximately 672kN. How would i simulate this on the rotor as a shock load? I could do it as a static load would that give the same results? Also how do i know if the bearings would survive the impact? Thanks

2. Apr 12, 2014

### AlephZero

The first step is to find how much of your "crash force" is actually felt by the rotor. That depends on the relative masses of the car and the rotor, and how flexible the car structure is.

A fairly straightforward approach would be to assume the bearings are rigid and apply an acceleration to the rotor, opposite to the acceleration of the car as it crashes, Rotordynamic effects like gyroscopic forces may or may not be significant, depending on the design of the rotor and its speed, but in any case it would be a good idea to get the model giving sensible results with the rotor not spinning before you include the rotordynamics.
First define "survive". Do you mean the rotor doesn't fall out of the car, or that it will still do whatever it is supposed to do after the crash?

3. Apr 12, 2014

### Webbd050

Ahhh okay so what equation would i use to calculate the acceleration? I haven't got a figure for the time of the crash. By survive i mean the rotor isnt going to fly off the bearings and embed itself in someones head. Thanks

4. Apr 12, 2014

### AlephZero

You know the force. You should be able to guess the mass of the car even if you don't know it exactly. Force = mass x acceleration.