It Looks Like a Cube—Why Is the 2024 Honda N-BOX Cd Only 0.40? (CFD)

I CFD-simulated the 2024 Honda N-BOX Turbo at 80 and 120 km/h — and the result surprised me: Cd = 0.40. In this video, we follow the airflow around the N-BOX (pressure, velocity, dynamic pressure, and streamlines) to explain why a boxy kei car can behave very differently from a true cube in the wind. Key result (this CFD scenario): • Drag coefficient: Cd 0.40 (80 & 120 km/h) • Vertical force: near-neutral (about 0.1 kgf downward) Chapters 00:00 Streamlines + the Cd result 00:53 Front stagnation and windshield behavior 04:45 A-pillars and side-edge separation 06:50 Roof attachment (why the radius matters) 08:45 Underbody flow + rear underbody ramp 10:40 Wheels and wheel-wake effects 11:59 Rear spoiler and wake control 12:30 120 km/h comparison 14:30 Lift / stability discussion 15:10 Improvements and what I would change Want to learn CFD or aerodynamics? Take one of our courses in: OpenFOAM Automotive Aerodynamics RC Airplane Design & Manufacturing Want your own car analyzed? I take commissioned simulations and deliver the same type of outputs you see in this video (streamlines, cut-planes, wake analysis, and force results). #HondaNBOX #Aerodynamics #CFD Notes / disclaimers This is a simulation-based analysis (CFD) for entertainment purposes, not an official manufacturer wind-tunnel certification. Results depend on modeling assumptions, boundary conditions, and geometry representation.