(a) Click the Fluent Database... button to open the Fluent Database Materials panel.
i. Select nitrogen (n2) from the list of Fluent Fluid Materials.
ii. Click Copy to copy the information for nitrogen to your list of fluid materials. iii. Close the Fluent Database Materials panel. (b) Close the Materials panel.
Step 4: Boundary Conditions. Define /Boundary Conditions...
1. Set the boundary conditions for the fluid (fluid).
(a) Select nitrogen from the Material Name drop-down list. (b) Click OK to close the Fluid panel.
2. Set the boundary conditions for the substrate (substrate).
(a) Select nitrogen from the Material Name drop-down list.
(b) Enable the Porous Zone option to activate the porous zone model.
(c) Enable the Laminar Zone option to solve the flow in the porous zone without turbulence.
(d) Click the Porous Zone tab. i. Make sure that the principal direction vectors are set as shown in . Use the scroll bar to access the fields that are not initially visible in the panel.
ii. Enter the values in Table for the Viscous Resistance and Inertial Resistance. Scroll down to access the fields that are not initially visible in the panel.
(e) Click OK to close the Fluid panel.
3. Set the velocity and turbulence boundary conditions at the inlet (inlet).
(a) Enter m/s for the Velocity Magnitude.
(b) Select Intensity and Hydraulic Diameter from the Specification Method dropdown list in the Turbulence group box.
(c) Retain the default value of 10% for the Turbulent Intensity. (d) Enter 42 mm for the Hydraulic Diameter. (e) Click OK to close the Velocity Inlet panel.
4. Set the boundary conditions at the outlet (outlet).
(a) Retain the default setting of 0 for Gauge Pressure.
(b) Select Intensity and Hydraulic Diameter from the Specification Method dropdown list in the Turbulence group box.
(c) Enter 5% for the Backflow Turbulent Intensity. (d) Enter 42 mm for the Backflow Hydraulic Diameter. (e) Click OK to close the Pressure Outlet panel.
5. Retain the default boundary conditions for the walls (substrate-wall and wall) and close the Boundary Conditions panel.
Step 5: Solution
1. Set the solution parameters. Solve /Controls /Solution...
(a) Retain the default settings for Under-Relaxation Factors. (b) Select Second Order Upwind from the Momentum drop-down list in the Discretization group box.
(c) Click OK to close the Solution Controls panel.
2. Enable the plotting of residuals during the calculation. Solve/Monitors /Residual...
(a) Enable Plot in the Options group box.
(b) Click OK to close the Residual Monitors panel.
3. Enable the plotting of the mass flow rate at the outlet. Solve / Monitors /Surface...
(a) Set the Surface Monitors to 1.
(b) Enable the Plot and Write options for monitor-1, and click the Define... button
