Wind Loading

Wind loading analyses simulate the air flow and resultant structural loading on buildings, large signs, and other structures. Examples include:

Application Examples

Flow Over and around buildings

Wind Loading on windows, signs, lightboards, and façades

Modeling Strategy

A volume surrounding the device must be constructed. In most cases the surrounding volume is an open environment:

These items and several more are presented in detail in the AEC Geometry Modeling topic...

Materials

Assign Air to all air regions.

Note that in most external flow applications, buoyancy effects are negligible, and the Environment setting should be set to Fixed. An important benefit of this is that the flow solution is independent of the temperature distribution. This means that the flow and heat transfer solutions can be run independently. The benefits include faster simulation times and the flexibility to run multiple thermal analyses using the same flow solution.

The default air properties are set for 68 °F. If the operating temperature is greater than 90 °F or less than 50 °F, modify the Scenario Environment temperature to the appropriate value. This ensures the air density is appropriate for the operating conditions.

Several other material types are commonly used in AEC applications:

Click here for more about materials in AEC applications...

Boundary Conditions

The boundary conditions for wind loading analyses are straightforward:

Mesh

A basic guideline for a high-quality analysis model is that the mesh distribution be sufficient to resolve the flow and temperature gradients efficiently. In regions where the flow circulates or experiences large gradients (such as in wakes, vortices, and separation regions), a finer mesh is required.

For most models, use Automatic Sizing to define the mesh distribution. It may be necessary to locally refine the mesh on geometric features that are highly detailed. For more information about Mesh Autosizing and model preparation...

In some cases, it may be necessary to adjust the Minimum Refinement Length to reduce their effect on the overall mesh count.

To locally refine the mesh in high-gradient flow regions:

Running

On the Physics tab of the Solve dialog:

On the Control tab of the Solve dialog:

The specified number of iterations, 750, is the maximum number of iterations that will run. (This has been found to be sufficient for most mechanical ventilation simulations.) Autodesk Simulation CFD stops the solution when either 750 iterations have been completed or when the solution reaches convergence, whichever comes first. If heat transfer and Automatic Forced Convection are enabled, Autodesk Simulation CFD automatically solves for the temperature distribution after the flow solution is complete.

Additional Solver Capabilities

Results Extraction

For more general information, use the extensive collection of results visualization tools to extract flow and thermal results.