Forchheimer Drag

Right-click the Fluid and Matrix Properties node to add a Forchheimer Drag feature proportional to the square of the fluid velocity. Brinkman equations consider the drag of the fluid on the porous matrix to be proportional to the flow velocity, in the same fashion as with Darcy’s law.

D O M A I N S E L E C T I O N

From the Selection list, choose the domains to define the Forchheimer drag. The default is to add all domains.

F O R C H H E I M E R D R A G

Enter a value for the Forchheimer coefficient F (SI unit: kg/m4).

Initial Values

The Initial Values feature adds initial values for the velocity field u and the pressure p that can serve as an initial condition for a transient simulation or as an initial guess for a nonlinear solver.

D O M A I N S E L E C T I O N

From the Selection list, choose the domains to define initial values.

I N I T I A L V A L U E S

Enter values or expressions for the initial value of the Velocity field u (SI unit: m/s) and the Pressure p (SI unit: Pa). The default values are 0.

Mass Source

The Mass Source node adds a mass source (or mass sink) Qbr (SI unit: kg/(m3·s)) to the right-hand side of Equation 10-4. This term accounts for mass deposit and/or mass creation in porous domains. The interface assumes that the mass exchange occurs at zero velocity.

D O M A I N S E L E C T I O N

From the Selection list, choose the domains to define a mass source. Only Porous Matrix domains are available.

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