How to prepare the geometry for simulation?
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FEB 2020, Support Team

How to prepare the geometry for simulation?

Before you start a simulation, here are some instructions to prepare the model correctly and get the best out of a simulation with Ingrid Cloud. These instructions apply for Wind Load and Wind Comfort applications.

Starting note

When the model is inserted inside the wind tunnel, Ingrid Cloud will find the lowest level of the geometry to set the point for the ground level. And the wind profile will interact with everything above that.

Bottom plates and ground level

Wind Comfort and Wind Load applications simulate airflow in an urban environment, so objects can’t be floating. All geometries and buildings must be placed on the same level – unless topography is being modeled, see instructions ahead.

Models don’t need a bottom plate. Ingrid Cloud automatically creates a “floor" under the model before starting the simulation.


plate-6-.pngIf your model contains a bottom plate with "zero thickness”, and covers approximately the same area as the rest of the model, it won’t be a problem, your simulation should work. 

Detailed models

Remove small details. Features such as balconies and stairs have little influence on the results at the pedestrian level. You should only keep balconies if you specifically want to study comfort on them. The fewer the details, the faster your simulation will finish.


All volumes must be closed

Since we are analysing external wind flow behaviour, all openings must be closed. Please, shut all doors, windows or any other openings.


For Wind Comfort simulations, include surrounding buildings 

In Wind Comfort simulations, in order to better represent the flow near the area of interest, we recommend the inclusion of all surrounding buildings within a radius of at least 200 metres around the area you want to study.

Important note: Currently, the maximum model extension allowed is 1.2 km.

File format and size

Ingrid Cloud supports 11 different file formats. The best file format to use is STL, because there’s virtually no limit for file size. For all the other supported formats, a maximum of 50 megabytes is recommended.

Supported files:

  • STL
  • STEP
  • DXF
  • IGES
  • OBJ
  • LAS
  • 3DS
  • IFC
  • DWG
  • ASC


Topography instructions

Create a slope connecting topography to the “ground level”


Keep in mind: the edges of the model cannot be too thick or too high so that it does not disrupt or influence the airflow. The best way to set up a model for a wind tunnel simulation is by preparing a slope underneath the topography. The slope will act as a smooth path for the wind flow, allowing turbulence to be correctly predicted around your area of interest.


Ingrid Cloud will take the lowest level of your geometry to automatically set the ground level. All structures modeled on top of your terrain should be contained within the slope or the terrain area.


Extension of topography and overall model size

We recommend the area covered by topography (and its slope) to be at most 20% larger than the area of interest. The maximum model extension allowed is 1.2 km.

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