Flow conditions and fluid properties
1. Flow conditions: inviscid, viscous, laminar, or
2. Fluid properties: density, viscosity, and
thermal conductivity, etc.
3. Flow conditions and properties usually presented in dimensional form in industrial commercial CFD software, whereas in non-dimensional variables for research codes.
Selection of models: different models usually fixed by codes, options for user to choose
Initial and Boundary Conditions: not fixed by codes, user needs specify them for different applications.