[DAmaral]

Hi,

I need to simulate the air flow inside a building, but i want to take account the impact of surrounding buildings. The façade elements and inside partitions needs to be detailed, so if I define only one mesh for inside and outside, it will be huge.

Is there a way to define two meshes, one for inside and other for outside, and simulate outside mesh first, and use it's results to define boundary conditions for the inside boudary?

It's attached a image to exemplify the problem. This is a simple model that i'm using to study how to simulate my problem.

Thank in advance.

[ghorrocks]

You can do the large scale model with a coarse geometry for the facade. Then extract the velocity profile a distance back and use that profile as the boundary condition for a high resolution model of the facade.

But if I was doing this I probably would not bother. Doing it all together is going to be easier and more accurate. I have done simulations of domains 100km x 100km x 10km which I have refined the mesh in the region of interest down to 10m mesh resolution. The simulation runs fine in about 40GB of RAM which is easy to come by these days. And note ICEM is my recommended meshing package for meshes like this. A description of the model is here if you are interested https://www.computationalfluiddynami...ation-mystery/