Experimental study for the hydraulic efficiency of an overtopping type wave energy converter with a circular runup ramp

Abstract

In this study, overtopping rates on a circular cylindrical overtopping ramp under regular waves have been measured and hydraulic efficiency of the device as a wave energy converter has been assessed by analyzing the energy budget of the overtopped water mass. The study has been carried out by conducting two-dimensional physical model tests. The variation of overtopping rates with wave parameters has been studied and an empirical formula has been evaluated for the estimation of overtopping rates. The efficiency of the system has been calculated as the ratio of the mean power of the overtopped water mass to the wave energy flux. Results indicate that the hydraulic efficiency based on the kinetical komponent can reach 40% for the case of steep waves and the efficiency is reduced with increasing wavelength.

Keywords

• Wave overtopping,wave energy converter,hydraulic efficiency

Dairesel yüzeyli aşma tipi bir dalga enerjisi dönüştürücüde hidrolik verimin deneysel incelenmesi

Abstract

Bu çalışmada, dairesel silindir formundaki bir tırmanma yüzeyi üzerinde düzenli dalgalar etkisinde meydana gelecek aşma debileri ölçülmüş ve aşan su kütlesinin enerji bütçesinden yola çıkılarak sistemin bir dalga enerjisi dönüştürücü olarak hidrolik verimi incelenmiştir. İki boyutlu fiziksel modelleme teknikleri uygulanarak gerçekleştirilen çalışmada aşma debilerinin dalga parametreleri ile değişimi incelenmiş ve debilerin tahmini için ampirik bir bağıntı önerilmiştir. Hidrolik verim, aşan su kütlesinin ortalama gücünün dalga enerji akısına oranı cinsinden elde edilmiştir. Çalışma, özellikle kısa periyodlu dalgalarda yapının %40'a yakın bir hidrolik verim sağladığını göstermekte olup verimin artan dalga boyu ile azaldığını ortaya koymuştur.

Keywords

• Dalga aşması,dalga enerjisi dönüştürücü,hidrolik verim

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