Parameter for mass density.

[SS4598]

• I want to use parameters for assigning material to parts in assembly. What is key difference between PTC_MASS_DENSITY and MP_DENSITY?. Which one would be correct to assign density using parameters.

Additionally what is correct syntax to assign material to part using parameter. As when I use PTC_MASS_MATERIAL = Aluminum it displays error. 

[Chris3 · Accepted solution]

MP_DENSITY is user editable pre-multibody parameter that still works but only for single body parts. For instance if you are modeling a part that has a known weight regardless of size you could write a relation like:

MP_DENSITY = 5 / PRO_MP_VOLUME

The mass of the part would always be 5.

PRO_MP_DENSITY is a reported density that is the average of all of the densities of the bodies and their associated materials. IE body1 density + body2 density / # Bodies

PTC_MASS_DENSITY is the parameter in the material file (.mtl) that defines the density for that material.

PRO_MP_ALT_DENSITY is linked to MP_DENSITY unless you change it and then the link is broken. PRO_MP_ALT_DENSITY is changed by defining mass properties manually (File -> Prepare -> Mass Properties -> Change -> Define Properties by "Fully Assigned" -> Type in a density number)

Had enough density?

[SS4598]

Thank you!!