RYURAKU vs ViscousJoukowski

RYURAKU is an interactive educational simulation app for experiencing fluid dynamics phenomena firsthand. Developer: Fuji Bit Inc. The 6th title in the SUUGAKU / BUTURAKU / DENRAKU / HARAKU / NETURAKU series. The theme is "flow." Discover the wonders of fluid physics through 12 hands-on simulations. 12 simulations in 3 categories: - Flow basics - Streamlines: particles reveal potential flow around a cylinder in a uniform stream. Drag the obstacle and watch the flow field change in real time. - Bernoulli's Principle: flow through a Venturi tube with live pressure gauges. Watch speed rise and pressure drop where the pipe narrows, and see A1v1 = A2v2 at work. - Reynolds Number: laminar-turbulent transition in pipe flow. Adjust speed, viscosity and diameter and see the dramatic change at Re ≈ 2300. - Boundary Layer: a boundary layer growing over a flat plate, from the laminar Blasius solution to turbulent transition at Re_x ≈ 5×10^5. - Darcy's Law: slow flow through porous media such as sand or rock. Adjust permeability, pressure gradient and porosity to experience q = (k/μ)·∇P, the law behind groundwater, oil reservoirs and filters. - Vortices & lift - Vortex: point vortices and their mutual induction. Tap to add a counterclockwise vortex, long-press for clockwise. - Kármán Vortex Street: alternating vortex shedding behind a cylinder, with live Strouhal and Reynolds numbers. - Lift Force: flow around an airfoil and how lift and drag arise. Change the angle of attack or camber and watch the force vectors. - Magnus Effect: asymmetric flow and a sideways force on a spinning cylinder: the physics of curveballs and banana kicks. - Water & gravity - Buoyancy (new): Archimedes' principle. Change the object and fluid densities to find where things float, sink or hang in balance. Drag the object under, let go, and watch it bob until it settles with a submerged fraction of ρ_s/ρ_f. - Torricelli's Law (new): water jetting from a hole in a tank. See the exit speed v = √(2gh), the falling water level and the jet range R = 2√(y₀h). Drag the hole to find the height that throws the water farthest. - Surface Wave: free-surface gravity waves. As the depth-to-wavelength ratio changes, particle orbits shift smoothly from circles (deep water) to flattened ellipses (shallow water). Features: - Real-time parameter adjustment for every simulation - A hint on how to try each screen, plus an explanation with formulas - Live physics formulas and values - Works with large text sizes, landscape, iPad and Split View - Taps and drags can also be done with buttons and sliders (works with VoiceOver and Switch Control) - 16 languages (English, Japanese, Chinese Simplified / Traditional, Korean, Spanish, Portuguese, German, French, Hindi, Indonesian, Russian, Italian, Turkish, Thai, Vietnamese) - Dark mode / Light mode Pricing & ads: - Free. No in-app purchases, subscriptions or paid unlocks - A banner ad (Pangle) is shown at the bottom of the screen - Ads are personalized only if you allow tracking (ATT). You can also turn off personalized ads from "About this app" > "Ad settings" Recommended for: - Students studying fluid dynamics in physics class - Anyone who wants to understand how flow behaves - Teachers looking for interactive teaching materials - Anyone interested in aeronautics or fluid mechanics

Are you interested in fluid dynamics? Viscous Joukowski simulates the flow around a Joukowski airfoil by solving the two-dimensional incompressible Navier–Stokes equations directly on your device. For teachers, students, and curious aerodynamicists, it provides an interactive way to explore how viscosity changes lift, drag, pressure, boundary layers, separation, and wake formation. Watch vorticity, speed, pressure, and streamlines evolve around the airfoil. Change the angle of attack, thickness, and camber by dragging directly on the flow field, or use precision controls. Adjust the Reynolds number to explore steady flow, separated wakes, starting vortices, and vortex shedding. Surface-pressure curves and aerodynamic-force estimates update as the simulation develops. The app also includes the classical analytical Joukowski potential-flow solution. Overlay it on the computed viscous pressure distribution to see where the ideal textbook model agrees with—or departs from—the Navier–Stokes result. In the potential solution, circulation is selected using the Kutta condition; in the viscous simulation, circulation and the wake develop dynamically from the no-slip flow. All calculations run locally using Apple MLX and GPU-accelerated Fourier methods. No server, account, or cloud computation is required.