AION
Research paperImage, Video & 3D Generation · Training & Scaling1 source · Oct 7, 2026

Conditional Flow Matching for Generation of 3D Multi-variable Instantaneous Urban Microclimate Fields

Rapid and accurate prediction of urban wind and temperature fields is important for urban microclimate design and climate adaptation.

Key points

  • Large-eddy simulation (LES) effectively resolves these instantaneous fields, but its application is limited in iterative design of urban microclimate applications due to high computational cost.
  • This paper adopts a novel generative framework of Conditional Flow Matching (CFM) that uses building geometry and mean flow as guidance to generate plausible three-dimensional instantaneous velocity and temperature fields for urban microclimate in seconds.
  • Against reference LES data, the CFM surrogate can rapidly and accurately restore the first-order statistics with Normalized Root Mean Square Error (NRMSE) of 2.99% for wind and 1.77% for temperature, second-order turbulence metrics with NRMSE of 7.17% for wind and 8.84% for temperature, turbulent kinetic energy with NRMSE of 7%, probability density function and vertical profiles in representative locations.
  • Wind engineering application of local gust prediction demonstrate that the speed and accuracy of CFM, supporting the use of generative AI for making turbulence-aware resilient urban design and climate adaptation more computationally feasible.

Sources (1)

Extractive summary: sentences quoted from the sources.