TY - JOUR
T1 - Anomalous wave statistics following sudden depth transitions
T2 - application of an alternative Boussinesq-type formulation
AU - Bonar, Paul A.J.
AU - Fitzgerald, Colm J.
AU - Lin, Zhiliang
AU - van den Bremer, Ton S.
AU - Adcock, Thomas A.A.
AU - Borthwick, Alistair G.L.
PY - 2021
Y1 - 2021
N2 - Recent studies of water waves propagating over sloping seabeds have shown that sudden transitions from deeper to shallower depths can produce significant increases in the skewness and kurtosis of the free surface elevation and hence in the probability of rogue wave occurrence. Gramstad et al. (Phys. Fluids 25 (12): 122103, 2013) have shown that the key physics underlying these increases can be captured by a weakly dispersive and weakly nonlinear Boussinesq-type model. In the present paper, a numerical model based on an alternative Boussinesq-type formulation is used to repeat these earlier simulations. Although qualitative agreement is achieved, the present model is found to be unable to reproduce accurately the findings of the earlier study. Model parameter tests are then used to demonstrate that the present Boussinesq-type formulation is not well-suited to modelling the propagation of waves over sudden depth transitions. The present study nonetheless provides useful insight into the complexity encountered when modelling this type of problem and outlines a number of promising avenues for further research.
AB - Recent studies of water waves propagating over sloping seabeds have shown that sudden transitions from deeper to shallower depths can produce significant increases in the skewness and kurtosis of the free surface elevation and hence in the probability of rogue wave occurrence. Gramstad et al. (Phys. Fluids 25 (12): 122103, 2013) have shown that the key physics underlying these increases can be captured by a weakly dispersive and weakly nonlinear Boussinesq-type model. In the present paper, a numerical model based on an alternative Boussinesq-type formulation is used to repeat these earlier simulations. Although qualitative agreement is achieved, the present model is found to be unable to reproduce accurately the findings of the earlier study. Model parameter tests are then used to demonstrate that the present Boussinesq-type formulation is not well-suited to modelling the propagation of waves over sudden depth transitions. The present study nonetheless provides useful insight into the complexity encountered when modelling this type of problem and outlines a number of promising avenues for further research.
KW - Boussinesq-type equations
KW - Freak wave
KW - Kurtosis
KW - Rogue wave
KW - Skewness
UR - http://www.scopus.com/inward/record.url?scp=85107560577&partnerID=8YFLogxK
U2 - 10.1007/s40722-021-00192-0
DO - 10.1007/s40722-021-00192-0
M3 - Article
AN - SCOPUS:85107560577
SN - 2198-6444
VL - 7
SP - 145
EP - 155
JO - Journal of Ocean Engineering and Marine Energy
JF - Journal of Ocean Engineering and Marine Energy
IS - 2
ER -