The configuration effect of flapping foils for energy harvesting

The configuration of multiple flapping foils is studied via numerical simulations. We comprehensively consider the effects streamwise distance, vertical spacing, and phase difference on energy harvesting performance foils. divide foil configurations into three categories: tandem, unaligned, parallel. tandem optimal for if using existing efficiency formula. However, expand diffusion range wake turbulence. Wake has a critical effect configurations, utilization spacing been neglected. Here, effective angle attack velocity are proposed based foils, which can well predict various rules lift coefficient guide studies simple parallel system 135°, decreases with increasing spacing. stepwise maximizes making it practical engineering applications. not only recycles upstream but also utilizes to enhance from turbines. In downstream over achieved first time configuration.