Speaker 2 :  Hidetaka Houtani  (University of Tokyo)
    Date & Time : December 17th (Fri.), 2021 / 10:50-11:30PM (Tokyo (JST)) 
    Title : On the maximum crest height of modulated wave trains
    Abstract : 
         The crest-height amplification of modulated wave trains is investigated 
       numerically and experimentally. In the experiment, the maximum crest height 
       of modulated wave trains normalized by their initial amplitude is found to be 
       increased with the initial wave steepness in the non-wave-breaking regime. 
       From the corresponding numerical simulations, we revealed that the increase 
       of the normalized maximum crest height at the peak of the modulation is 
       a consequence of enhanced spectral broadening. The spectral broadening is 
       more pronounced with larger initial wave steepness because of the intensified 
       quasi-resonant interaction. Moreover, despite spectral broadening, 
       the self-focusing (phase convergence) of modulated wave trains was confirmed.