Pixel Wind Tunnel vs Benchbuilt

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.

Benchbuilt turns vehicle engineering into a hands-on learning lab. Start with a production-inspired body, choose an engine, configure the drivetrain and chassis, then shape the body and test the result. Every choice feeds a physics-based estimate using real units and understandable explanations. Compare power, mass, frontal area, drag coefficient, traction, gearing, braking, and engine packaging without needing an engineering degree. BUILD YOUR VEHICLE • Choose from compact, fastback, roadster, sports sedan, and open-engine hot rod body packages • Install engines ranging from an efficient four-cylinder to high-output V8 packages • See whether the engine fits beneath the body or protrudes into the airflow • Configure transmission, tires, brakes, suspension, chassis weight, and fuel • Shape independent body control points to explore smooth profiles, wedges, and experimental designs TEST AND LEARN • Estimate top speed and 0–60 mph acceleration • Measure quarter-mile time and trap speed • Compare standing-mile speed, lateral grip, braking distance, and cruise range • Run road and wind-tunnel tests • Understand why drag, weight, power, traction, and gearing changed each result • Save builds for side-by-side engineering comparisons Designed for curious builders, students, classrooms, and anyone who has wondered why one car shape performs better than another. Benchbuilt works on iPhone and includes a spacious iPad workbench for classroom use. Benchbuilt provides educational physics estimates and is not intended for real-world vehicle certification or safety decisions.