Geometric and Control Optimization of a Two Cross-Flow Turbine Array

TL;DR

This study experimentally optimizes the performance of a two-cross-flow turbine array in a recirculating water channel by exploring various configurations and control strategies, revealing how turbine interactions affect overall efficiency.

Contribution

It introduces an experimental framework for optimizing two-turbine arrays with different configurations and control methods, highlighting the effects of co- and counter-rotation on performance.

Findings

Tip-speed ratio control improves individual turbine efficiency.

Coordinated control enhances array synchronization.

Array configuration significantly influences turbine interactions.

Abstract

Cross-flow turbines, also known as vertical-axis turbines, convert the kinetic energy in moving fluid to mechanical energy using blades that rotate about an axis perpendicular to the incoming flow. In this work, the performance of a two-turbine array in a recirculating water channel was experimentally optimized across sixty-four unique array configurations. For each configuration, turbine performance was optimized using tip-speed ratio control, where the rotation rate for each turbine is optimized individually, and using coordinated control, where the turbines are optimized to operate at synchronous rotation rates, but with a phase difference. For each configuration and control strategy, the consequences of co- and counter-rotation were also evaluated. We hypothesize how array configurations and control cases influence interactions between turbines and impact array performance.