SimScale: Importing geometry

Hi, in this video, I will start to show you how to perform wind simulation of urban areas using the online SimScale platform. The first thing we need to do is import a model that we’ve created previously, for example, in Revit or SketchUp. So here on the left hand side, you can click the plus icon on the geometries and upload almost any file, any model file that you may have, and then SimScale imports this and shows you a quick representation of what the model looks like. And you have some control over this view and what it will look like using the buttons here at the top.

The first thing we then need to do is to translate this model of the buildings to a model of the wind tunnel that we will actually be simulating. So we will edit this model in the CAD mode. So once you go there, you see the same model as before. The first thing we will do is to define an external flow volume. And we can then specify the dimensions that this wind tunnel should have. So the bottom will usually be at zero meters, so it matches that, so it matches the bottom of the buildings that we have.

And for the height of the model, there is a rule of thumb that says that if the highest building is, say, 20 meters high, you use six times that height as the height of the wind tunnel. And in the same way, you can also specify the other directions so that the - If the wind will be coming from the right hand side of the view here, we want five times that height of the tallest building on the right hand side, on the bottom, and at the top. And we want around 15 times the height and the downwind side of the model.

So with those basic dimensions set up, we can then use this seed face option and we can simply select a roof of a building. This isn’t always necessary, but sometimes we need to do this so SimScale can figure out how to create this volume. And then we simply click apply and it will create this box representing the wind tunnel that we will be simulating.

So then we just need to get rid of all the buildings that we added because they won’t be part of the simulation, so you can either use this view on the right here to select all of the buildings, or you can also simply select the volume of the wind tunnel and then right click to invert that selection. So if you look underneath, you can see that all the buildings are selected. And with all the buildings selected, we can simply delete them from the model.

So as you’ll see the buildings have now disappeared, but the imprints of the buildings are still present in the wind volume that we will be simulating later on. And you can simply click Export to return to the CFD environment. And there you will once again see the wind tunnel volume that we have just created. In the next video, I’ll go over all the settings you need to put up before we can start the simulation.