Boundary Condition Fidelity and Outlet Capacity Effects in a Passive Wind Concentrator: Correcting Idealized Assumptions

This work presents a fidelity-driven reassessment of a passive wind concentrationconcept previously evaluated using idealized Computational Fluid Dynamics (CFD)boundary conditions. Earlier simulations employing prescribed velocity inlets suggested substantial internal velocity amplification. In the present study, the entire geometry is embedded in an external computational domain to allow natural atmosphericinteraction.Comparative analysis demonstrates that while idealized boundary conditions overpredict acceleration, meaningful internal velocity can still be achieved under realisticexternal flow if sufficient outlet capacity is provided. Designs with insufficient downstream area exhibit stagnation and velocity reduction, whereas a constant-width slitconfiguration restores internal velocity levels closer to the idealized case. The resultsestablish that boundary condition fidelity and outlet flow capacity jointly govern performance in passive wind concentration systems.