Performance analysis of a sea javelin wave energy converter in irregular wave

Wave energy, as a kind of eco-friendly energy due to its wide distribution and high energy density, has become a hot research topic at home and abroad and is likely to become a new industry in the future. In this article, we adopt a sea javelin wave energy converter (SJ-WEC) which is a floating vertical axisymmetric buoy. At first, semi-analytical solution of SJ-WEC is studied using eigen-function in frequency domain. Then, wave force and hydrodynamic coefficients of frequency domain can be applied into impulse response function (IRF) method to obtain motion and power of SJ-WEC. In the end, we can select ISSC wave spectrum and JONSWAP wave spectrum to represent the irregular wave to apply into IRF method. It is shown and confirmed that the motion and power which are calculated by IRF method are the same as the frequency domain method's so that the results of irregular waves can be confirmed it accurate. The IRF method is applied to the computation of irregular waves in time domain to simulate the real situation in actual sea conditions which are random and irregular.