Improving energy extraction in VAWT clusters: effect of blade count, wake synergy, and inter-turbine spacingD. V. G. Prasad, Mayank Verma, G. Dinesh Kumar Reddy and Ashoke DeEur. Phys. J. Spec. Top., (2025) 1-21DOI: https://doi.org/10.1140/epjs/s11734-025-01818-2