Pressure load
Pressure load
(OP)
Hi-I asked this question in another discussion group on eng-tips but was advised to post here instead -I did not get satifactory replies in the that group (NX-UG) as well
I have just been reading the tutorial in NX (as well as practising doing it) concerning pressure loads in NX.
Now, if you recall the definition of pressure (http://wiki.answers.com/Q/Why_pressure_is_scalar_q...)
we see pressure is a scalar.
This is clear.
However, in NX if we go to load type->PRessure, in the dialog box, there is also an option of defining the components of pressure.
My question is, how can pressure ahve a unique direction?
Sorry for a very fundamental question-please note this is not a homework question but very much a question from me- working on real problems.





RE: Pressure load
in most cases you should see pressure as normal to the surface, thus scalar.
i guess NX is saying if you have an inclined load on the surface, that you want to distribute over an area then you's have normal and in-plane components; yes?
Quando Omni Flunkus Moritati
RE: Pressure load
RE: Pressure load
In that case (applied load distributed over an area)- it is strictly 'not' pressure, it is a distributed traction.
Strictly going by the definition of pressure, it acts in all directions and is described by the magnitude alone.
RE: Pressure load
Quando Omni Flunkus Moritati
RE: Pressure load
force over area will have a direction (force is a vector)
Quando Omni Flunkus Moritati
RE: Pressure load
Definition from Wikipedia:
"Pressure is force per unit area applied in a direction perpendicular to the surface of an object"
If the "surface" does not have a defined direction (such as for pressure at a point in a fluid) then pressure is a scalar.
If the surface does have a defined direction (such as for pressure applied to a surface in a finite element analysis) then pressure is a vector.
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/