Learning Forum

[Aaron Dang]

I'm working on a simulation using explicit dynamics and when I import the model from solidworks as  .STEP file, ANSYS says that my mass is 0.91576kg

However, the energy is showing up as

According to 1/2mv^2, I should be looking at a number closer to 16mJ. When I evaluate it via solidworks, I'm given 187.38g

by solving for the mass using the ansys energy and my velocity of 6m/s, we get the mass from my solidworks model, but the properties tab in ansys is giving 915g. There is a disconnect between the mass that ANSYS is giving me versus the energy that I should be seeing with respect to the ANSYS mass. Is there an explanation here or some kind of bug?

[Ram Gopisetti]

Hi Aaron Dang, 

Let's get some checks done here. 

1) How can Solidworks compute the mass with no density added? let us verify in terms of spaceclaim tool 

Having no proper material used for this part, the mass is not computed; adding some density, the mass gets computed. So, what is the basis of the third-party tool in evaluating the mass? How can we say this is correct?

2) When transferred to explicit dynamics or any mechanical application, the mass computed is based on true material density, which is correct. Check the curve for the kinetic energy, not the maximum over time, as any transfer of energy or inertia will spike up this value. You should see that the part starts with the true KE (0.5*m*v_in) and then changes as per the simulation behavior over time.

There is no bug here; it's just missing sanity checks.

Cheers, Ram