Urban ventilation plays a crucial role in maintaining air quality and mitigating the heat island effect in urban areas. It facilitates the movement of fresh air, disperses pollutants, and regulates temperature, creating a healthier and more comfortable environment for residents. Proper urban ventilation design and planning can contribute to reducing air pollution, improving the overall livability of cities, and enhancing the well-being and quality of life of urban dwellers. In this context, the present study investigates the relationship between drag parameters and ventilation efficiency in urban-like regular arrays, with the aim of uncovering correlations that can enhance the understanding of airflow dynamics in urban environments. Three-dimensional computational fluid dynamics (CFD) simulations employing the standard k-ε turbulence model are performed. These arrays are sorted into two groups: the first consists of cubic arrays with various wall-to-wall distances, while the second comprises cuboid arrays with various side widths. The planar area density (λ_P) ranges from 0.0625 to 0.56. Grid sensitivity test and validation against wind tunnel data are conducted, followed by simulations under the same inflow conditions. The drag force (F), drag coefficient (C_d), spatially averaged velocity (U_ave), and air change rate (ACH) are calculated. According to the results, F shows a significant increase for 0.0625 < λ_P < 0.25 and a slight decrease for 0.25 < λ_P < 0.56, while Cd shows a linear increase with λ_P. The further linear regression analysis shows that U_ave and ACH are strongly negatively correlated with F and C_d, which supports the effectiveness of drag parameters in reflecting ventilation efficiency, particularly for evaluating urban block-scale ventilation. These findings could have significant implications for urban planning, architectural design, and the development of sustainable and efficient urban spaces.