The growing demand for sustainable energy highlights the need for efficient small-scale wind turbines, especially in urban areas with low wind speeds and limited space. This study experimentally examines aerodynamic augmentation effects on turbine performance using shrouds and tailored flanges. Four turbine configurations—a bare turbine, a turbine with a simple shroud, a shroud with a vertical flange, and a shroud with an improved curved flange—were 3D printed and tested in a controlled wind tunnel under realistic low- to moderate-speed urban wind conditions. Airflow velocity at the shroud throat and corresponding power output were measured across various wind speeds. Results show that both flange curvature and height significantly affect aerodynamic performance. The curved-flange design consistently increased throat velocity and turbine output, achieving up to a 32.3-fold power gain over the bare turbine at 5 m/s. At higher wind speeds, differences among augmented configurations decreased, yet the improved curved flange still delivered approximately 4.3 times the output of the bare turbine at 16.35 m/s. These findings emphasize the importance of outlet geometry in lowering startup thresholds, sustaining airflow acceleration, and maximizing energy capture. Overall, this study provides robust experimental evidence that shrouds with improved curved flanges significantly enhance small-scale urban wind turbine efficiency, offering a practical solution for low-wind energy harvesting and guiding future designs for improved performance across diverse wind regimes.