Boundary Conditions

test

test

Table of Contents

• 1. Boundary conditions
  • 1.1. Neumann boudary condition vs Dirichlet BC
  • 1.2. wall
  • 1.3. inlet
  • 1.4. outlet
  • 1.5. symmetry
    • 1.5.1. properties
  • 1.6. periodic
  • 1.7. outflow

1 Boundary conditions

 

1.1 Neumann boudary condition vs Dirichlet BC

for Neumann BC, the normal derivative of a variable is prescribed For, Dirichlet BC, the value of a variable ( velocity, pressure, etc_ is prescribed

1.2 wall

1.3 inlet

1.4 outlet

1.5 symmetry

 

1.5.1 properties

1. zero normal velocity at a symmetry plane
2. zero normal gradients of all variables at a symmetry plane
3. no convective flux
4. no diffusion flux

1.6 periodic

1.7 outflow

outflow BC

the detail of the flow velocity and pressure are not known

(no term)

A zero diffusion flux for all flow variables.

(no term)

An overall mass balance correction.

(no term)

flow is assumed as fully-developed

(no term)

no any conditions at outflow boundaries

(no term)

the outflow information is extrapolated from the interior

limits: if the flow may produce a recirculation at the outlet or if the flow field is not stable and fully developed at the outlet, then a pressure outlet boundary condition is preferred.

Author: kaiming

Created: 2019-02-24 Sun 20:09

Emacs 24.5.1 (Org mode 8.2.10)

Validate