Where infrared.city fits
3,204,804 simulations run on Infrared Core (as of 29 Oct 2026).
infrared.city runs 12 models from one engine, Infrared Core, among them wind, wind comfort, sun, daylight, radiant heat and felt heat (UTCI). It works on real 3D building and terrain meshes, in a browser app, through an API and SDK, and in plugins for Grasshopper, QGIS and ArcGIS. Felt heat for 1 km² takes about 5 s once the geometry is uploaded, and 400 km² took 44 s as four 100 km² runs in parallel. Run times are not like for like across tools: area, grid, simulated hours and physics differ. Sun, sky and radiant heat come from ray tracing. Wind comes from an AI model trained on CFD results, not from a CFD run for each request.
- You need a whole district or city, as well as one site.
- You test many massing and street options in one session.
- You run studies from your own tools through the API and SDK.
- You need an hourly city layer for a digital twin.
Use both
Screen massing and street options for the whole area in infrared.city. Send the chosen building to a CFD study or to consulting engineers when the project needs it, for example for cladding wind loads.
Facts side by side
| infrared.city | Orbital Stack | |
|---|---|---|
| Method | Ray tracing for sun, sky and radiant heat; wind from an AI model trained on CFD results (no CFD run per request) | AI estimates; rapid RANS CFD; detailed CFD and LES through RWDI consulting |
| Run time | About 5 s for 1 km² of felt heat (UTCI, 08 to 18 h, geometry uploaded, measured); 400 km² in 44 s (four runs in parallel) | AI: estimates "in seconds"; CFD: results "within 2-3 business days" |
| Inputs | Real 3D building and terrain meshes, weather data; trees and ground materials for heat | STL files from CAD; buildings within a 300 m radius, under 3.5 km² of surface |
| Outputs | 12 models, among them wind, wind comfort, sun, daylight, radiant heat and felt heat (UTCI) | Wind comfort, thermal comfort, solar, airflow, cladding wind loads |
| Runs as | Cloud: browser app, API and SDK, plugins | Browser app |
| Licence and pricing | Tokens: free start with 900 tokens, plans from €240 a year | Price per run on the vendor list: about $100 AI wind, about $350 CFD wind |
The run times are not like for like: the AI estimates and the CFD runs differ in area, inputs and physics from infrared.city.
The infrared.city values repeat the full comparison. Each value for Orbital Stack comes from the sources below.
Sources
- Orbital Stack: AI-powered wind simulations , accessed 24 Oct 2026.
- Orbital Stack help: add new scenario , accessed 24 Oct 2026.
- Orbital Stack help: preparing the geometry , accessed 24 Oct 2026.
- Orbital Stack: purpose-built CFD , accessed 24 Oct 2026.
- Orbital Stack: climate analysis overview , accessed 24 Oct 2026.
- Orbital Stack: pricing , accessed 24 Oct 2026.