Author(s)

Ridho Hantoro, I Ketut Aria Pria Utama, Juniarko Pranandand, Erna Septyaningrum

Corresponding Author

Ridho Hantoro

ABSTRACT

The performance of array configuration is strongly influenced by the freestream velocity, turbines position, turbines spacing and turbines rotational direction. Many studies have been conducted to examine this issue. This current study aims to investigate the effect of turbines rotational direction on the array performance and determines the array configuration which provides farm effectiveness improvement. Vertical Axis Hydrokinetic Turbine-Darrieus Straight Blade Cascaded (VAHT-SBC) was employed in this study, as it has better performance and self-starting characteristic. Three configurations were tested and simulated, i.e. “co-rotating”, “counter-rotating out” and “counter-rotating in”. The array testing process and numerical study confirmed that the array performance was highly affected by the hydrodynamic interaction between turbines. The hydrodynamic interaction leads to the superposition of induced flow and freestream flow, producing the jet-type flow-field or canal effect. Hence, it enhances the array performance. Since “co-rotating” configuration has better farm effectiveness and independent to the incoming flow direction, this configuration is recommended for unstable source which has unpredictable incoming flow direction. The farm effectiveness of “co-rotating” configuration is 1.33 at freestream velocity of 1.3 m/s and cross-stream distance of 1.5D.

KEYWORDS

Array configuration, co-rotating, counter-rotating, Darrieus Straight Blade Cascaded, farm effectiveness.