sites and site species, and full multi-component/thermal diffusion effects are also included in the simulation.

The purpose of this tutorial is to demonstrate surface reaction capabilities in ANSYS Fluent. Convective heat transfer is considered to be the dominant mechanism compared to radiative heat transfer, thus radiation effects are ignored.

15.4. Setup and Solution

The following sections describe the setup and solution steps for this tutorial:

15.4.1.Preparation

15.4.2.Reading and Checking the Mesh

15.4.3.Solver and Analysis Type

15.4.4.Specifying the Models

15.4.5.Defining Materials and Properties

15.4.6.Specifying Boundary Conditions

15.4.7.Setting the Operating Conditions

15.4.8.Simulating Non-Reacting Flow

15.4.9.Simulating Reacting Flow

15.4.10.Postprocessing the Solution Results

15.4.1. Preparation

To prepare for running this tutorial:

1.Download the surface_chem.zip file here.

2.Unzip surface_chem.zip to your working directory.

3.The file surface.msh can be found in the folder.

4.Use Fluent Launcher to start the 3D version of ANSYS Fluent.

Fluent Launcher displays your Display Options preferences from the previous session.

For more information about the Fluent Launcher, see starting ANSYS Fluent using the Fluent Launcher in the Fluent Getting Started Guide.

5.Ensure that the Display Mesh After Reading option is enabled.

6.Ensure that the Serial processing option is selected.

7.Enable Double Precision.

15.4.2. Reading and Checking the Mesh

1.Read in the mesh file surface.msh.

File → Read → Mesh...

2.Check the mesh.

Domain → Mesh → Check → Perform Mesh Check

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ANSYS Fluent will perform various checks on the mesh and will report the progress in the console. Ensure that the reported minimum volume is a positive number.

3.Scale the mesh.

Domain → Mesh → Scale...

Scale the mesh to meters as it was created in centimeters.

a.Select cm (centimeters) from the Mesh Was Created In drop-down list in the Scaling group box.

b.Click Scale and verify that the domain extents are as shown in the Scale Mesh dialog box.

The default SI units will be used in this tutorial, hence there is no need to change any units.

c.Close the Scale Mesh dialog box.

d.Re-display the mesh

e.Click the Fit to Window icon, .

4.Check the mesh.

Domain → Mesh → Check → Perform Mesh Check

Note

It is a good practice to check the mesh after manipulating it (scale, convert to polyhedra, merge, separate, fuse, add zones, or smooth and swap). This will ensure that the quality of the mesh has not been compromised.

5.Examine the mesh (Figure 15.2: Mesh Display (p. 507)).

Figure 15.2: Mesh Display

Extra

You can use the left mouse button to rotate the image and view it from different angles. Use the right mouse button to check which zone number corresponds to each boundary. If you click the right mouse button on one of the boundaries in the graphics window, its name and type will be printed in the ANSYS Fluent console. This feature is especially

useful when you have several zones of the same type and you want to distinguish between them quickly. Use the middle mouse button to zoom the image.

15.4.3. Solver and Analysis Type

Retain the default solver settings of pressure-based steady-state solver in the Physics tab (Solver group).

Physics → Solver

15.4.4. Specifying the Models

In this problem, the energy equation and the species conservation equations will be solved, along with the momentum and continuity equations.

1. Enable heat transfer by turning on the energy equation.

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Physics → Models → Energy

2.Enable chemical species transport.

Physics → Models → Species...

a.Select Species Transport in the Model list.

The Species Model dialog box will expand to show relevant input options.

b.Retain the selection of mixture-template from the Mixture Material drop-down list. You will modify the mixture material later in this tutorial.

c.Retain the default setting for Diffusion Energy Source.

This includes the effect of enthalpy transport due to species diffusion in the energy equation, which contributes to the energy balance, especially for the case of Lewis numbers far from unity.