Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Density in a Deforming Bar

Please login with a confirmed email address before reporting spam

When I apply a force to a rectangular prism with one fixed end such that it deforms under tension, it appears that volume is not conserved. The bar lengthens, but there is no other visible deformation and the density across the structure appears to remain constant (when I do a volume plot of the density it remains constant). Does anyone know why Comsol doesn't appear to conserve mass in this case and what I must do to "convince" it to do so?

I have attached an example.


1 Reply Last Post 22 apr 2015, 02:12 GMT-4
Henrik Sönnerlind COMSOL Employee

Please login with a confirmed email address before reporting spam

Posted: 9 years ago 22 apr 2015, 02:12 GMT-4
Hi.

The following quote from the user's guide may be helpful:

"The variable solid.rho represents a “reference” or “initial” density ρ0, and not the “current” density ρ. If you are interested in finding the density of the deformed material (the density in the spatial frame), you can compute it using the expression solid.rho/solid.J."

Regards,
Henrik
Hi. The following quote from the user's guide may be helpful: "The variable solid.rho represents a “reference” or “initial” density ρ0, and not the “current” density ρ. If you are interested in finding the density of the deformed material (the density in the spatial frame), you can compute it using the expression solid.rho/solid.J." Regards, Henrik

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.