Pixel Wind Tunnel vs Engine Lab

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.

Build an engine and hear it run. Engine Lab is a touch-first engine simulator: design anything from a single to a V12, then hear it idle, rev and pull to the limiter, live on your iPhone or iPad. BUILD BENCH • Set the layout, 1 to 12 cylinders, bore, stroke, firing order and redline. • Hear each change as you make it, and hold to rev. • Try different headers, exhausts and mufflers. • Compare against a saved version by ear or on the dyno. SEE IT IN 3D • Every engine, including your own builds, becomes a 3D model driven by the live simulation: pistons, crank, cams, valves and glowing headers. • Orbit, zoom, slow it down, switch between X-ray and solid, and tap any part for live readings. The classic 2D cutaway is one tap away. DRIVE IT • Manual or automatic gearbox with clutch and road speed, plus a gearing chart with top speed in each gear. • Simulated dyno pulls with torque and power curves. • Six built-in engines: Honda B18C5 VTEC, Honda TRX520 single, BMW M52B28, Toyota 2JZ, Audi 2.3 inline-5 and GM LS V8. IMPORT AND SHARE • Import engine-sim .mr scripts and share your builds as .mr files. • Export a WAV recorded by the on-device simulator. No account, network service or microphone permission is required. An optional one-time Pro purchase unlocks advanced tuning and unlimited saved builds; the free plan keeps three. Values are simulated estimates for exploration, not certified engineering measurements.