# Documentation du code de simulation numérique SUNFLUIDH

## Web LIMSI

sunfluidh:inlet_outlet_boundary_conditions_examples

## Example of inflow/outflow boundary conditions

• This example is defined for a 2D geometrical configuration. The size of the domain is $1.5 \times 1.0.$
• The flow is homogeneous (no multi-species gas)
• An inlet is located at the down left side of the domain (red line on the figure).
• An outlet is located at the top right side of the domain (green line on the figure).
• Conditions are constant in time

(inlet in red line, outlet in green line, remaining walls in blue lines)

## Inflow data

### Example 1

• The flow is homogeneous (no multi-species gas)
• Conditions are constant in time
 &Inlet_Boundary_Conditions
Type_of_BC= "INLET", Direction_Normal_Plan= 1 ,
Plan_Location_Coordinate= 0.0   ,
Start_Coordinate_of_First_Span = 0.0, End_Coordinate_of_First_Span = 0.5,
Start_Coordinate_of_Second_Span= 0.0  , End_Coordinate_of_Second_Span= 0.0 ,
Flow_Direction= 1 ,
Normal_Velocity_Reference_Value= 1.0  ,
Temperature_Reference_Value= 293.0 ,
Density_Reference_Value=  1.2,
Define_Velocity_profile= 0 ,
End_of_Data_Block= .true. /

### Example 2

Not for the release SUNFLUIDH_EDU

• The flow is homogeneous (no multi-species gas)
• The temperature and the density are constant.
• The normal velocity component is time-dependent :
• The function is sinusoidal. The mean value of the time function is given by “Normal_Velocity_Reference_Value”.
• the frequency is 10 Hz
• The magnitude is 40% of the mean inlet velocity
 &Inlet_Boundary_Conditions
Type_of_BC= "INLET", Direction_Normal_Plan= 1 ,
Plan_Location_Coordinate= 0.0   ,
Start_Coordinate_of_First_Span = 0.0, End_Coordinate_of_First_Span = 0.5,
Start_Coordinate_of_Second_Span= 0.0  , End_Coordinate_of_Second_Span= 0.0 ,
Flow_Direction= 1 ,
Normal_Velocity_Reference_Value= 1.0  ,
Temperature_Reference_Value= 293.0 ,
Density_Reference_Value=  1.2,
Define_Velocity_profile= 0 ,
Time_Fct_Name= "Sinus" , Time_Fct_Threshold= 0.0 ,
Time_Fct_Time_Scale= 0.1 , Time_Fct_Magnitude= 0.4 ,
End_of_Data_Block= .true. /

## Outflow data

### Example 1

• The outflow is based on the mass flowrate conservation.
• The normal pressure gradient is zero (Neumann boundary condition).

&Outlet_Boundary_Conditions

 Type_of_BC= "OUTLET", Direction_Normal_Plan= 1 ,
Plan_Location_Coordinate= 1.5   ,
Start_Coordinate_of_First_Span = 0.5    , End_Coordinate_of_First_Span = 1.0 ,
Start_Coordinate_of_Second_Span= 0.0    , End_Coordinate_of_Second_Span= 0.0 ,
Flow_Direction= 1 ,
End_of_Data_Block= .true. /


### Example 2

Not for the release SUNFLUIDH_EDU

• The outflow is based on pressure conditions.
• The (dynamic) pressure value is given by “Pressure_Reference_Value”. It is imposed out of the domain and located at a distance “Length_Scale” from the outflow plan (Robin condition).
• Keep in mind that the pressure is here related to the dynamics, not to the thermodynamics of the flow. It is therefore defined from a reference value which can be null.

&Outlet_Boundary_Conditions

 Type_of_BC= "FREEBC", Direction_Normal_Plan= 1 ,
Plan_Location_Coordinate= 1.5   ,
Start_Coordinate_of_First_Span = 0.5    , End_Coordinate_of_First_Span = 1.0 ,
Start_Coordinate_of_Second_Span= 0.0    , End_Coordinate_of_Second_Span= 0.0 ,
Flow_Direction= 1 ,
Pressure_Reference_Value       = 0.0    , Length_Scale= 0.2 ,
End_of_Data_Block= .true. /

sunfluidh/inlet_outlet_boundary_conditions_examples.txt · Dernière modification: 2018/12/15 14:56 de yann