Enter the pressure at the boundary (SI unit: Pa) in the p0 field.

No Viscous Stress

This boundary condition sets the viscous stress to zero at the boundary:

	ul	+ ul	T		2
l l + T				–	3--	ul I n = 0

G A S B O U N D A R Y C O N D I T I O N

From the Gas boundary condition list, select a boundary condition for the dispersed phase at outlets.

• Gas Boundary Conditions Equations

See Also

Symmetry

The Symmetry feature adds a boundary conditions that describe symmetry boundaries in a fluid-flow simulation. The boundary condition for symmetry boundaries prescribes no penetration and vanishing shear stresses:

ul n = 0,		l l		ul	+ ul	T		2
	t		+ T				–	3--	ul I n = 0

B O U N D A R Y S E L E C T I O N

From the Selection list, choose the boundaries that are symmetry boundaries.

	A boundary condition for 2D axial symmetry is not required.
	For the symmetry axis at r 0, the software automatically provides a
2D Axi	condition that prescribes ur 0 and vanishing stresses in the z direction
	and adds an Axial Symmetry feature to the model that is valid on the axial
	symmetry boundaries only.

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