Performance analysis and geometric optimization of bladeless wind turbines using wake oscillator model

Abstract

This study addresses the critical challenge of optimizing bladeless wind turbines (BWTs) for maximum power extraction while maintaining structural integrity. BWTs represent an innovative approach to wind energy harvesting from vortex-induced vibrations, but their performance characteristics and design constraints remain poorly understood. We present a comprehensive analytical framework combining a nonlinear wake oscillator model with fully coupled elastic-rigid body dynamics to investigate BWT behaviour across a wide parameter space. Unlike previous studies relying on high-fidelity computational modelling or simplified analytical models, our approach enables rapid exploration of complex relationships between BWT geometry, power output, and structural safety. The results reveal a previously unrecognized trade-off: while increasing mast diameter enhances both power extraction and efficiency, maximum power (600 Watts) and peak efficiency (6%) are achieved through distinct geometric configurations. Notably, configurations optimized solely for power output often exceed structural safety limits, while those maximizing efficiency deliver suboptimal power generation. The optimal BWT configuration (mast diameter 0.65 m, length 0.8 m) achieves 460 Watts output while maintaining structural integrity - a significant finding for practical BWT implementation. This study provides the first comprehensive BWT design methodology that balances performance optimization with structural constraints, establishing a foundation for scaling up these promising renewable energy devices.