Ambient – the same flow parameters which are specified at the computational domain boundaries in External analyses (i.e. the parameters specified as initial and ambient conditions in the Wizard or the General Settings dialog: a combination of two independent thermodynamic parameters (static pressure, temperature and density), velocity parameters, substance concentrations, and turbulence parameters). See “Specify Initial and Ambient Conditions”.
During the calculation they act in the same manner, as in External analyses.
Impulse – the same flow parameters (fluid temperature, density, substance concentrations, and turbulence parameters) which are specified at the computational domain boundaries in External analyses, with the exception of specifying fluid impulse instead of fluid velocity (both are vectors).
During the calculation they act nearly in the same manner, as in External analyses.
Velocity – the same flow parameters (fluid velocity, temperature, density, substance concentrations, and turbulence parameters) which are specified at the computational domain boundaries in External analyses.
During the calculation they act nearly in the same manner, as in External analyses.
Static pressure – the same flow parameters (static pressure, temperature, substance concentrations, and turbulence parameters) which are specified in the Pressure Openings set of boundary conditions when you select the Static Pressure type of this boundary condition.
During the calculation they act nearly in the same manner, as a pressure opening with the Static Pressure boundary condition.
Total pressure – the same flow parameters (total pressure, temperature, substance concentrations, and turbulence parameters) which are specified in the Pressure Openings set of boundary conditions when you select the Total Pressure type of this boundary condition.
During the calculation they act nearly in the same manner, as a pressure opening with the Total Pressure boundary condition.
Independently of the Transferred Boundary Condition type selected from the above-mentioned variants, if the boundary’s section lies in the solid and the Conduction option is enabled in the current Flow Simulation project and was enabled in the Flow Simulation project which results are taken as the transferred boundary condition, then the solid temperature is taken from this project’s results as the transferred solid boundary condition, whereas the heat flux obtained as the problem’s solution at this boundary depends on the heat transfer in this solid, and in particular can be non-zero.
When specifying boundary conditions for an Internal analysis you must take care of their physical compatibility. For example, a project will not run for internal steady-state flows if at model inlets and outlets you specify boundary conditions of the Flow opening type (or Transferred Boundary Condition of the Velocity type) without any boundary condition of the Pressure Opening type, so the inlet and outlet mass flow rates are not balanced exactly.
To avoid such problems we recommend that you specify at least one pressure condition (Boundary Condition of the Pressure Opening type or Transferred Boundary Condition of the Static (Total) Pressure type) and at least one Boundary Condition of the Flow Opening type or Transferred Boundary Condition of the Velocity (or Impulse) type.