Boundary Conditions
Table of contents
Overview
Boundary conditions determine the flow conditions interior to the calculation domain. At a minimum, the boundary conditions need to be physically realistic and representative of the problem you are trying to solve.
Inflow and Outflow BC
Consider the simple case of incompressible flow in a duct with one inlet and one outlet
Using the nomenclature of StarCCM+, the simplest types of inlet velocity boundary condition for incompressible flow are
- Velocity inlet
- Mass flow inlet
- Pressure
and the simplest kinds of outflow boundary conditions
- Outlet (least constrained)
- Pressure outlet
There are other ways of prescribing the inflow and outflow conditions including look-up tables and analytical formulas for non-uniform velocity profiles. However, for our immediate purpose, we want to focus on the allowable combinations of the simple inlet and outlet specifications. Refer to the details in the following notes.