# Symmetry and Symmetry local

Submitted by Perbear on March 10, 2014 - 14:51

Symmetry and Symmetry Local are useful for simulation of symmetric bodies.

Symmetry local mirrors existing body at an arbitrary selected flat surface (which I understand) but Symmetry local mirrors existing body at either X+Y, Y+Z, Z+X planes (which I also understand) or X, Y or Z (which I don't understand)?

Also, when using symmetry, does the all forces sum up, i.e., does drag and lift monitor for the rotating wheel example (which use local symmetry) show 50% or |00% of total drag, lift of the wheel?

## Symmetry Planes Definition

Conditions->Symmetry(distinct fromConditions->Symmetry Local) on thePhysicsTool Palette mirrors the 3D View Window in various planes relative to a coordinate system.Xis the X=0 plane,Yis the Y=0 plane, andZis the Z=0 plane.X+Ymirrors both X=0 and Y=0, as shown in section"Use Symmetry to View the Entire Simulation"in the tutorial "Incompressible Flow Through a Pipe into a Box".Symmetry does not change the force or any other sum-based variables. For the symmetrical wheel tutorial the drag and lift are 50% of the totals for a full wheel.

## Symmetry

Thank you for the explanation, it was very helpful!