Urban City Grid: Realistic Building Network
A realistic urban environment with 7 buildings of mixed orientations (4 horizontal + 3 vertical) arranged in a city grid pattern. The domain is 1200x600 with street width set to 2x building width for realistic urban canyon proportions. Three inlet wind configurations (East, South, West) demonstrate how wind direction affects flow patterns through the building network.
Setup
| Parameter | Value |
|---|---|
| Domain | 1200 x 600 (NX x NY) |
| Reynolds number | Re = 100 |
| Building count | 7 (4 horizontal + 3 vertical) |
| Building dimensions | 80 x 160 (width x height) |
| Street width | 160 (2x building width) |
| Inlet configurations | East, South, West wind |
| Collision | MRT (Multi-Relaxation Time) |
| Boundary conditions | Zou/He velocity inlet, convective outlet |
Inlet Configurations
Steady-State Comparison
Drag the handle to compare velocity contour (left) and streamlines (right).
Velocity Field
Interactive canvas viewer with Play/Pause + frame scrubber.
Pressure Coefficient Cp
Cp = (p - p_ref) / (0.5 * rho_inf * U_inf^2). Red = high pressure (stagnation), blue = low pressure (separation).
Pressure Coefficient Cp
Vorticity Field
Vorticity omega = dv/dx - du/dy. Red = counter-clockwise rotation, blue = clockwise rotation.
Vorticity Field
Flow Physics
The city grid creates complex urban aerodynamics:
- Channeling effect: Wind funneled between parallel buildings accelerates through narrow streets
- Wake interference: Downstream buildings sit in the wake of upstream structures, reducing effective wind speed
- Corner vortices: Strong recirculation zones form at building corners where flow separates
- Canyon recirculation: Stable vortices form between closely spaced buildings
- Direction-dependent patterns: Different inlet directions activate different street canyons and flow paths
Key Findings
- East wind creates strong channeling through horizontal streets
- South wind activates vertical street canyons with vortex formation
- West wind creates opposite flow patterns to east wind with different wake interactions
- Mixed building orientations create 3D-like flow complexity in 2D simulation
- Street width = 2x building width provides realistic urban canyon proportions