Work

Coupled and uncoupled CFD-based design strategies for diffuser-augmented wind turbines: A comparative study

Year: 2024

Type: article

Abstract: Most of the current design methodologies for ducted wind-turbines rely on an uncoupled design-procedure of the duct and the rotor. The aim of this work is to assess, for the first time, the reliability of this strategy by quantifying the differences with an advanced fully-coupled approach. Therefore, two different aero-designs are performed using these strategies. In the uncoupled approach the duct geometry is optimized to maximize the ingested mass flow rate disregarding the rotor presence. Then, a free-vortex disk is introduced, and its load is varied to maximize the power coefficient based on the device frontal-area ( ). In the coupled design, the duct geometry and the rotor load are simultaneously optimized. In both cases, the CFD-actuator-disk is used as analysis method along with a gradient-based optimizer. The coupled strategy yields a higher (0.68) adopting a compact diffuser and high stagger-angle. Contrarily, the uncoupled procedure leads to a lower (0.59) using a large chord and a moderate stagger. A physical explanation of these differences is offered. Finally, while the presented cases refer to a given shape of the duct, the conceptual generality of the study in terms of the effective reliability of the uncoupled design remains valid in general.

Source: Energy

DOI: 10.1016/j.energy.2024.134159

Authors: R. Bontempo, E.M. Di Marzo, M. Manna

Institution: University of Naples Federico II

Language: English

Topic: Wind Energy Research and Development

Subfield: Aerospace Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $4,140