One of the most promising technologies for sea-wave energy conversion is the one based on the OWC principle. In a system of this type, the oscillatory motion of the sea waves is converted into a bi-directional air flow which is commonly exploited by means of a self-rectifying turbine such as the Wells turbine, the simplest and most reliable device for this purpose. The vast majority of experiments on Wells turbines and OWC devices has analyzed their performance from a global point of view, often in experimental facilities where the turbine was operated under stationary flow conditions. This paper presents the results of the experimental investigation carried out on a Wells turbine, by measuring the flow field both upstream and downstream of the rotor, in a laboratory set-up capable to reproduce the bi-directional airflow typical of an OWC system. The investigation aims to evaluate the local performance of the Wells turbine under unsteady flow conditions. The experimental measurements allow the identification of the loss components that affect the performance of the turbine. Viscous losses, due to the aerodynamic of the rotor cascade, represent the main contribution to the total losses, and appear larger than kinetic energy losses at the machine exhaust.

Detailed investigation of the local flow-field in a Wells turbine coupled to an OWC simulator

Licheri F.
;
Ghisu T.;Cambuli F.;Puddu P.
2022

Abstract

One of the most promising technologies for sea-wave energy conversion is the one based on the OWC principle. In a system of this type, the oscillatory motion of the sea waves is converted into a bi-directional air flow which is commonly exploited by means of a self-rectifying turbine such as the Wells turbine, the simplest and most reliable device for this purpose. The vast majority of experiments on Wells turbines and OWC devices has analyzed their performance from a global point of view, often in experimental facilities where the turbine was operated under stationary flow conditions. This paper presents the results of the experimental investigation carried out on a Wells turbine, by measuring the flow field both upstream and downstream of the rotor, in a laboratory set-up capable to reproduce the bi-directional airflow typical of an OWC system. The investigation aims to evaluate the local performance of the Wells turbine under unsteady flow conditions. The experimental measurements allow the identification of the loss components that affect the performance of the turbine. Viscous losses, due to the aerodynamic of the rotor cascade, represent the main contribution to the total losses, and appear larger than kinetic energy losses at the machine exhaust.
Aerodynamic probes; Components of loss; Experimental analysis; OWC systems; Turbine efficiency; Wells turbines
File in questo prodotto:
File Dimensione Formato  
TGhisu_J30.pdf

Solo gestori archivio

Descrizione: articolo online
Tipologia: versione editoriale
Dimensione 1.65 MB
Formato Adobe PDF
1.65 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11584/343132
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact