Manufacturing Solutions

# Inflow Boundary

The Inflow boundary type is used to impose conditions at the inlet boundary.

Syntax

Inflow Inlet

(X_Velocity = Ux| X_Traction = tx ,

Y_Velocity = Uy| Y_Traction = ty,

Z_Velocity = Uz| Z_Traction = tz),

([Pressure = Pi],)

(Temperature Ti | HeatFlux = qin ),

(Strain = ε)

}

Comments

"Inlet" is the name of the user-specified inflow boundary. For each component of the momentum equation, you must specify either the inlet velocity or the tractions. The entities X_Velocity, Y_Velocity, and Z_Velocity are used to specify the primary degrees of freedom for each component of momentum equation. The entities X_Traction, Y_Traction, and Z_Traction are used to specify the secondary degrees of freedom. Pressure is specified only if tractions are imposed. Temperature or HeatFlux is specified for the energy equation when solving non-isothermal flows. The velocities, tractions, pressure, temperatures, and heat fluxes can be input as a function of space and time. An example of the imposition of space and time varying velocities is given in the Sample Input Files.

Valid data types for inflow boundary conditions are provided in the following table:

## Variable Name |
## Description |
## Valid Data Types |

Velocity (Ui) |
Velocity component (i=x,y,z) |
CONSTANT, EXPRESSION f(x,y,z,t) |

Traction (ti) |
Traction component (i=x,y,z) |
CONSTANT, EXPRESSION f(x,y,z,t) |

Pressure (P) |
Static pressure |
CONSTANT, EXPRESSION f(x,y,z,t) |

Temperature (T) |
Static temperature |
CONSTANT, EXPRESSION f(x,y,z,t) |

HeatFlux (q) |
Magnitude of surface heat flux |
CONSTANT, EXPRESSION f(x,y,z,t) |