Impact of Venturi-Effect Turbine Arrangements on Total Power Generation

Keming Gong

doi:10.6919/ICJE.202510_11(10).0006

Authors

Keming Gong

DOI:

https://doi.org/10.6919/ICJE.202510_11(10).0006

Keywords:

Venturi Effect Turbine; Turbine Array Layout; Wake Effects; Staggered Configuration; CFD.

Abstract

Venturi ducts accelerate incoming flows through geometric contraction and thereby enhance the power output of individual hydro-turbines. Nevertheless, when multiple turbines operate in an array, wake effects can substantially re-duce the overall efficiency, making the layout a critical factor in plant performance. In this study, two-dimensional computational fluid dynamics simulations were conducted to compare the flow fields and aggregate power of five Venturi-assisted turbines arranged in either a straight line or a staggered configuration. Moreover, the influence of tail-to-head spacing (8.67, 10.00, and 11.33 m) was systematically examined. The results demonstrate that, in the straight-line lay-out, the centerline velocity of downstream turbines decreases by approximately 75% relative to the upstream turbine, yielding only a marginal increase in total power (from 6.55 kW to 6.73 kW). By contrast, the staggered layout generates inter-row acceleration corridors, leading to inflow velocities higher than the free stream for all turbines, while the total power decreases as spacing increases (from 47.19 kW to 44.01 kW). Overall, the staggered arrangement delivers nearly sevenfold higher total power (≈ 701%) compared with the straight-line case. These findings highlight that staggered configurations with controlled inter-row spacing are essential for maximizing the efficiency of Venturi-turbine arrays, thereby providing theoretical guidance for the design of underwater power plants.

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