Pixel Wind Tunnel

Draw a shape. Tap Simulate. Watch real fluid dynamics come alive in pixels.

Pixel Wind Tunnel is a 2D fluid simulation app that runs real CFD (Computational Fluid Dynamics) calculations right on your device. No simplified approximations — the app solves the incompressible Navier-Stokes equations using the CIP advection method and Pressure Poisson solver, the same mathematical framework used in professional engineering software.

HOW IT WORKS

Draw any shape with your finger — airfoils, cars, buildings, anything
Tap Simulate
Watch the flow develop in real time
That's it. Real fluid physics in three steps.

SEE THE FLOW
Switch between visualization modes to explore different aspects of the physics:
• Velocity — where the flow speeds up and slows down
• Pressure — high and low pressure regions around your shape
• Vorticity — spinning structures and vortex shedding
• Streamlines — paths that fluid particles follow

MEASURE PERFORMANCE
Real-time aerodynamic coefficients calculated from surface pressure and viscous stress integration:
• Drag coefficient (Cd)
• Lift coefficient (Cl)
• Reynolds number

Draw two different shapes and compare which one has less drag. Understand why streamlined shapes work better — with real numbers, not guesswork.

EXPLORE DEEPER
• Place point probes anywhere to track velocity and pressure over time
• Scrub through simulation history with the timeline slider
• Adjust inlet velocity and viscosity to change flow conditions
• Save shapes with screenshots and reload them anytime

REAL CALCULATION, NOT AN ANIMATION
Every frame you see is computed from the actual Navier-Stokes equations. The CIP (Cubic Interpolated Propagation) method handles advection with minimal numerical diffusion, while the SOR iterative solver resolves the pressure field. Boundary conditions, viscous forces, and flow separation are all physically modeled.

FOR CURIOUS MINDS
Whether you're a student studying fluid mechanics, an engineer sketching quick ideas, a teacher demonstrating aerodynamics in class, or simply someone who wonders why things are shaped the way they are — draw it and find out.