External Aerodynamic Drag & Wake Separation Optimization for Commercial Heavy Transport
01. The Engineering Challenge
High highway cruising fuel consumption caused by massive low-pressure base wake separation and turbulent wheel well vortex shedding on a long-haul commercial transport configuration.
02. Technical Objective
Perform full-scale external aerodynamic CFD analysis to quantify drag contributors and develop passive aerodynamic add-ons to reduce overall drag coefficient (Cd).
03. Full-Scale CFD Simulation Methodology
Executed 3D transient Reynolds-Averaged Navier-Stokes (RANS) and detached eddy simulation (DES) over an 85-million polyhedral mesh with 15 prism layers ensuring y+ < 1 along all boundary surfaces.
04. Diagnostics & Aerodynamic Re-Profiling
Streamline and iso-vorticity diagnostics pinpointed 62% of total aerodynamic drag to the tractor-trailer gap cross-flow and rear door blunt base recirculating depression.
8.7% Reduction in Aerodynamic Drag Coefficient (Cd)
Strategic guide vanes and base fairing geometry effectively closed the trailing recirculating bubble, turning unrecoverable separation into a structured, pressure-recovering wake.