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

Year 2017, Volume: 19 Issue: 1, 118 - 131, 19.06.2017

Mehmet Adil Akgul , Mehmet Sedat Kabdaşlı

https://doi.org/10.25092/baunfbed.322406

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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