TY - JOUR

T1 - Force impact of long surface waves on a body semi-immersed in water. I. Influence of the waveform

AU - Gusev, Oleg I.

AU - Skiba, Vassiliy S.

AU - Khakimzyanov, Gayaz S.

N1 - Публикация для корректировки.

PY - 2022

Y1 - 2022

N2 - Purpose. Designing and operating semi-submerged fixed coastal structures requires taking into account the force effect of surface waves on them. This is especially true for those areas where such structures are located, where catastrophic tsunami waves are possible. In almost all research addressed the numerical study of the interaction of long surface waves with semi-submerged structures, a solitary wave was considered as an incoming wave. The purpose of this paper was to compare the effect of incident waves of different shapes. Methods. In the present work, a numerical algorithm based on a mathematical model of two-dimensional potential flows of an ideal fluid with a free boundary is employed to calculate the interaction of waves of various shapes with semi-immersed fixed structures. This model is one element of the hierarchy of hydrodynamic models and it can be considered as a “reference” model for problems in which fluid can be considered as ideal. It can be used to validate the shallow water models of the first and second long-wave approximations. The finite-difference equations and numerical algorithm are based on the curvilinear grids adapting to the free surface and taking into account irregularities of the body and basin bottoms. Results. We determine the dependencies of the maximum runup and wave force on the shape of incoming wave for the simplified formulation for vertical sides of a structure and horizontal bottoms of the structure and basin. The comparisons were made for the solitary and single waves, as well as for the leading-elevation and depression isosceles of N-waves. The calculations were performed for different values of the incident wave amplitude, depth, and body length. Differences in the patterns of interaction with the body of long waves of different types are revealed. Conclusions. For N-waves with a leading depression part, the maxima of runup on the face of the body are significantly greater than that for waves with other shapes. The impacts of the solitary and single waves on semi-immersed structures are similar. The wave that passed behind the body has smaller amplitude than the incoming wave, but maintains its shape for all wave types. As submergence and length of the body increases, the maximum run-up on the front face of the body and the horizontal component of the hydrodynamic force also increases, while the runup on the back face decreases. For greater body submergences, the horizontal force component approaches the impact of waves on a fixed vertical wall. In contrast to the solitary and solitary wave cases, the chronograms of the horizontal and vertical force components for N-waves with the leading depression part contain an area with a two-peak configuration even at relatively small amplitudes.

AB - Purpose. Designing and operating semi-submerged fixed coastal structures requires taking into account the force effect of surface waves on them. This is especially true for those areas where such structures are located, where catastrophic tsunami waves are possible. In almost all research addressed the numerical study of the interaction of long surface waves with semi-submerged structures, a solitary wave was considered as an incoming wave. The purpose of this paper was to compare the effect of incident waves of different shapes. Methods. In the present work, a numerical algorithm based on a mathematical model of two-dimensional potential flows of an ideal fluid with a free boundary is employed to calculate the interaction of waves of various shapes with semi-immersed fixed structures. This model is one element of the hierarchy of hydrodynamic models and it can be considered as a “reference” model for problems in which fluid can be considered as ideal. It can be used to validate the shallow water models of the first and second long-wave approximations. The finite-difference equations and numerical algorithm are based on the curvilinear grids adapting to the free surface and taking into account irregularities of the body and basin bottoms. Results. We determine the dependencies of the maximum runup and wave force on the shape of incoming wave for the simplified formulation for vertical sides of a structure and horizontal bottoms of the structure and basin. The comparisons were made for the solitary and single waves, as well as for the leading-elevation and depression isosceles of N-waves. The calculations were performed for different values of the incident wave amplitude, depth, and body length. Differences in the patterns of interaction with the body of long waves of different types are revealed. Conclusions. For N-waves with a leading depression part, the maxima of runup on the face of the body are significantly greater than that for waves with other shapes. The impacts of the solitary and single waves on semi-immersed structures are similar. The wave that passed behind the body has smaller amplitude than the incoming wave, but maintains its shape for all wave types. As submergence and length of the body increases, the maximum run-up on the front face of the body and the horizontal component of the hydrodynamic force also increases, while the runup on the back face decreases. For greater body submergences, the horizontal force component approaches the impact of waves on a fixed vertical wall. In contrast to the solitary and solitary wave cases, the chronograms of the horizontal and vertical force components for N-waves with the leading depression part contain an area with a two-peak configuration even at relatively small amplitudes.

KW - N-wave

KW - calculation results

KW - movable grid

KW - partially immersed structure

KW - potential flow model

KW - single wave

KW - solitary wave

KW - wave force

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85149692343&origin=inward&txGid=dda3a2bfb678bf0b84e9d19a95189f6d

UR - https://www.elibrary.ru/item.asp?id=49484388

UR - https://www.mendeley.com/catalogue/d5219859-13e0-3a5c-98c6-0d99890285a0/

U2 - 10.25743/ICT.2022.27.4.004

DO - 10.25743/ICT.2022.27.4.004

M3 - Article

VL - 27

SP - 33

EP - 62

JO - Вычислительные технологии

JF - Вычислительные технологии

SN - 1560-7534

IS - 4

ER -