Hydrodynamic Difference of Rectangular-Box Systems with and without Narrow Gaps

Topographic effects on wave resonance in the narrow gap between fixed box and vertical wall

“…Because the energy dissipation caused by the fluid viscosity, vortex shedding and even turbulence cannot be considered in the context of the potential flow theory, although both the theoretical analyses and the numerical simulations that are based on the potential flow model have been proved to predict the resonant frequency well, they were reported to overestimate the resonant wave height in the gap and the wave forces on the structures significantly. In order to overcome this deficiency, so far, several particular numerical techniques have been proposed to artificially produce and introduce the energy dissipation into the potential flow model (Chen, 2004;Huijsmans et al, 2001;Newman, 2004;Ning et al, 2015a, b). The comparisons between numerical and experimental results demonstrate that the potential flow model with the artificial energy dissipative term may estimate the resonant wave height and the corresponding wave forces satisfactorily (Lu et al, 2011a;Lu et al, 2011b).…”

On hydrodynamic characteristics of gap resonance between two fixed bodies in close proximity

“…Although both theoretical analyses and the numerical simulations based on the potential flow theory have been shown to predict the resonant frequency well, they were reported to significantly over-estimate the resonant wave height inside the gap and the wave forces on the floating bodies, because the physical energy dissipation due to the fluid viscosity, vortex shedding and even turbulences cannot be considered in the context of potential flow theory. To overcome this problem, several particular numerical techniques that artificially introduce wave energy dissipation term into the potential flow model were developed so far (Chen, 2004;Huijsmans et al, 2001;Lu et al, 2010b;Newman, 2004;Ning et al, 2015a, b). However, the introduction of artificial damping term seems somewhat arbitrary for the rigorous potential theory, and under some conditions it was found to be difficult to obtain a unique value of the damping parameter (Pauw et al, 2007;Tan et al, 2014).…”

Numerical investigations of wave loads on fixed box in front of vertical wall with a narrow gap under wave actions

“…Unfortunately, it was reported to remarkably over-predict the resonant wave height inside the gap and consequently cause the overestimation of the wave load on the structure. To address this issue, several special numerical methodologies have been proposed to suppress this unrealistic over-prediction (e.g., Chen (2004); Lu et al (2010b); Newman (2004); Ning et al (2015); Tan et al (2019)). Nevertheless, for these special methodologies, there always exist unknown dissipative coefficients.…”