Grouping waves simulation

• Main Authors: Tu, Shi-Sheng, 徐仕昇
• Other Authors: Gao, Jia-Zun
• Format: Others
• Language: zh-TW
• Published: 1990
• Online Access: http://ndltd.ncl.edu.tw/handle/14323683944556966569

碩士 === 國立成功大學 === 水利及海洋工程學系 === 78 === A process for generation of irregular wave trains in wave tank including given wave grouping characteristics has been developed in this paper. Wave grouping are controled by fitting, instead of random phase, the proper phase spectrum during the inverse FFT calculation. The process features the self calibration capability, so that the waves at any selected point in the wave tank match both the given wave spectrum and the grouping characteristics. The present proposed process has been proven to be very effective. The test results show that the errors of spectral zeroth order moments and spectral peak frequencies between target spectrums and measuring wave spectrums can be controlled under 1%. The errors of groupiness factors between 0.5 and 0.7 were under 10%. A series of tests has been carried out to examine the influence of the wave grouping on the statistical properties of the irregular waves. The result show that the statistical values of wave heights are significantly affected by wave grouping. For a given spectrum the maximum wave height, the one tenth wave height and the significant wave height increase with increasing groupiness factor(GF). whereas the average wave height and the root-mean-square wave height decrease as GF increases.