In this paper,the open-sourced computational fluid dynamics software,OpenFOAM~?,is used to study the fluctuation phenomenon of the water body inside a horizontally one-dimensional enclosed harbor basin with constant w...In this paper,the open-sourced computational fluid dynamics software,OpenFOAM~?,is used to study the fluctuation phenomenon of the water body inside a horizontally one-dimensional enclosed harbor basin with constant water depth triggered by falling wedges with various horizontal falling positions,initial falling velocities and masses.Based on both Fourier transfo rm analysis and wavelet spectrum analysis for the time series of the free surface elevations inside the harbor basin,it is found for the first time that the wedge falling inside the harbor can directly trigger harbor resonance.The influences of the three factors(including the horizontal falling position,the initial falling velocity,and the mass)on the response amplitudes of the lowest three resonant modes are also investigated.The results show that when the wedge falls on one of the nodal points of a resonant mode,the mode would be remarkably suppressed.Conversely,when the wedge falls on one of the anti-nodal points of a resonant mode,the mode would be evidently triggered.The initial falling velocity of the wedge mainly has a remarkable effect on the response amplitude of the most significant mode,and the latter shows a gradual increase trend with the increase of the former.While for the other two less significant modes,their response amplitudes fluctuate around certain constant values as the initial falling velocity rises.In general,the response amplitudes of all the lowest three modes are shown to gradually increase with the mass of the wedge.展开更多
Influences of topographic variations of the offshore fringing reef on the harbor oscillations excited by incident Nwaves with different amplitudes and waveform types are studied for the first time.Both the propagation...Influences of topographic variations of the offshore fringing reef on the harbor oscillations excited by incident Nwaves with different amplitudes and waveform types are studied for the first time.Both the propagation of the Nwaves over the reef and the subsequently-induced harbor oscillations are simulated by a Boussinesq-type numerical model,FUNWAVE-TVD.The present study concentrates on revealing the influences of the plane reef-face slope,the reef-face profile shape and the lagoon width on the maximum runup,the wave energy distribution and the total wave energy within the harbor.It shows that both the wave energy distribution uniformity and the total wave energy gradually increase with decreasing reef-face slope.The profile shape of the reef face suffering leading-elevation Nwaves(LEN waves)has a negligible impact on the wave energy distribution uniformity,while for leading-depression N-waves(LDN waves),the latter gradually decreases with the mean water depth over the reef face.The total wave energy always first increases and then decreases with the mean water depth over the reef face.In general,the total wave energy first sharply decreases and then slightly increases with the lagoon width,regardless of the reef-face width and the incident waveform type.The maximum runup subjected to the LEN waves decreases monotonously with the lagoon width.However,for the LDN waves,its changing trend with the lagoon width relies on the incident wave amplitude.展开更多
A series of numerical experiments from a barotropic configuration of the General Curvilinear Ocean Model (GCOM) was conducted to analyze the response to infragravity (IG) waves of the Port of Ensenada, located within ...A series of numerical experiments from a barotropic configuration of the General Curvilinear Ocean Model (GCOM) was conducted to analyze the response to infragravity (IG) waves of the Port of Ensenada, located within Bahia de Todos Santos (BTS), west coast of Mexico. Experiments with forcing frequencies f = 50?1 min?1, f = 30?1 min?1, f = 25?1 min?1 and f = 16.66?1 min?1 showed the expected increase of energy at the corresponding forcing frequency band and also the appearance of secondary peaks of energy at frequency bands f = 8.33?1 min?1 and f = 4.16?1 min?1 which were identified as modes f<sub>1 </sub>and f<sub>2</sub>;being the band at f = 16.66?1 min?1 the zeroth f<sub>0</sub> mode. Maximum peak of spectral energy from the numerical experiments was found at frequency band f<sub>0</sub> = 16.66?1 min?1 which agreed with the estimated maximum value of the amplification factor and with the T<sub>0</sub> mode of oscillation of the port. Distribution of amplitudes inside PE for modes f<sub>0</sub>, f<sub>1</sub> and f<sub>2</sub> were also presented. Mode f<sub>0</sub> represents a quarter-wave oscillation with amplitudes of the same sign;mode f<sub>1</sub> has two nodal lines and mode f<sub>2</sub> presents and additional one. Corresponding harbor currents were also calculated, they were in the range 20 - 160 cm?s?1. Finally, in order to elucidate the source of the external signals found in the spectral analysis of this study, the natural oscillation modes of the BTS were estimated. Although more studies are needed, BTS oscillation mode T<sub>2</sub> = 16.82 min, was identified as the external forcing that excites larger oscillations within the port.展开更多
In this paper, the long-term statistical properties of wave height in an idealized square harbor with a partial opening are studied. The incident waves are propagated into the harbor numerically by the finite/infinite...In this paper, the long-term statistical properties of wave height in an idealized square harbor with a partial opening are studied. The incident waves are propagated into the harbor numerically by the finite/infinite element method using three different wave models: (1) monochromatic wave train, (2) long-crested random wave train, and (3) short-crested random wave train. This study shows that for a given incident wave, the wave height in the harbor is affected by the wave model used. For long-term estimation of wave height exceedance probability, it is recommended that the waves be propagated into the harbor using the random wave model, and that wave heights be computed by use of the Rayleigh probability distribution.展开更多
基金financially supported by the National Natural Science Foundation of China (Grant No.51911530205)the Natural Science Foundation of Jiangsu Province (Grant No.BK20201455)+5 种基金the Guangdong Basic and Applied Basic Research Foundation (Grant No.2023A1515010890)the Key Laboratory of PortWaterway and Sedimentation Engineering of MOT (Grant No.YK222001-2)the Open Research Fund of Key Laboratory of Water Security Guarantee in Guangdong-Hong Kong-Marco Greater Bay Area of Ministry of Water Resources (Grant No.WSGBAKJ202309)the Qing Lan Project of Jiangsu Universitiesthe Royal Society (Grant No.IECNSFC181321)。
文摘In this paper,the open-sourced computational fluid dynamics software,OpenFOAM~?,is used to study the fluctuation phenomenon of the water body inside a horizontally one-dimensional enclosed harbor basin with constant water depth triggered by falling wedges with various horizontal falling positions,initial falling velocities and masses.Based on both Fourier transfo rm analysis and wavelet spectrum analysis for the time series of the free surface elevations inside the harbor basin,it is found for the first time that the wedge falling inside the harbor can directly trigger harbor resonance.The influences of the three factors(including the horizontal falling position,the initial falling velocity,and the mass)on the response amplitudes of the lowest three resonant modes are also investigated.The results show that when the wedge falls on one of the nodal points of a resonant mode,the mode would be remarkably suppressed.Conversely,when the wedge falls on one of the anti-nodal points of a resonant mode,the mode would be evidently triggered.The initial falling velocity of the wedge mainly has a remarkable effect on the response amplitude of the most significant mode,and the latter shows a gradual increase trend with the increase of the former.While for the other two less significant modes,their response amplitudes fluctuate around certain constant values as the initial falling velocity rises.In general,the response amplitudes of all the lowest three modes are shown to gradually increase with the mass of the wedge.
基金financially supported by the National Key Research and Development Program of China(Grant No.2017YFC1404200)the National Natural Science Foundation of China(Grant Nos.51911530205 and 51809039)+5 种基金the Natural Science Foundation of Jiangsu Province(Grant No.BK20201455)the Natural Science Foundation of the Jiangsu Higher Education Institutions(Grant No.20KJD170005)the Qing Lan Project of Jiangsu Universitiessupported by UK EPSRC(Grant No.EP/T026782/1)the Royal Academy of Engineering(Grant No.UK-CIAPP/73)the Royal Society(Grant No.IEC\NSFC\181321)。
文摘Influences of topographic variations of the offshore fringing reef on the harbor oscillations excited by incident Nwaves with different amplitudes and waveform types are studied for the first time.Both the propagation of the Nwaves over the reef and the subsequently-induced harbor oscillations are simulated by a Boussinesq-type numerical model,FUNWAVE-TVD.The present study concentrates on revealing the influences of the plane reef-face slope,the reef-face profile shape and the lagoon width on the maximum runup,the wave energy distribution and the total wave energy within the harbor.It shows that both the wave energy distribution uniformity and the total wave energy gradually increase with decreasing reef-face slope.The profile shape of the reef face suffering leading-elevation Nwaves(LEN waves)has a negligible impact on the wave energy distribution uniformity,while for leading-depression N-waves(LDN waves),the latter gradually decreases with the mean water depth over the reef face.The total wave energy always first increases and then decreases with the mean water depth over the reef face.In general,the total wave energy first sharply decreases and then slightly increases with the lagoon width,regardless of the reef-face width and the incident waveform type.The maximum runup subjected to the LEN waves decreases monotonously with the lagoon width.However,for the LDN waves,its changing trend with the lagoon width relies on the incident wave amplitude.
文摘A series of numerical experiments from a barotropic configuration of the General Curvilinear Ocean Model (GCOM) was conducted to analyze the response to infragravity (IG) waves of the Port of Ensenada, located within Bahia de Todos Santos (BTS), west coast of Mexico. Experiments with forcing frequencies f = 50?1 min?1, f = 30?1 min?1, f = 25?1 min?1 and f = 16.66?1 min?1 showed the expected increase of energy at the corresponding forcing frequency band and also the appearance of secondary peaks of energy at frequency bands f = 8.33?1 min?1 and f = 4.16?1 min?1 which were identified as modes f<sub>1 </sub>and f<sub>2</sub>;being the band at f = 16.66?1 min?1 the zeroth f<sub>0</sub> mode. Maximum peak of spectral energy from the numerical experiments was found at frequency band f<sub>0</sub> = 16.66?1 min?1 which agreed with the estimated maximum value of the amplification factor and with the T<sub>0</sub> mode of oscillation of the port. Distribution of amplitudes inside PE for modes f<sub>0</sub>, f<sub>1</sub> and f<sub>2</sub> were also presented. Mode f<sub>0</sub> represents a quarter-wave oscillation with amplitudes of the same sign;mode f<sub>1</sub> has two nodal lines and mode f<sub>2</sub> presents and additional one. Corresponding harbor currents were also calculated, they were in the range 20 - 160 cm?s?1. Finally, in order to elucidate the source of the external signals found in the spectral analysis of this study, the natural oscillation modes of the BTS were estimated. Although more studies are needed, BTS oscillation mode T<sub>2</sub> = 16.82 min, was identified as the external forcing that excites larger oscillations within the port.
文摘In this paper, the long-term statistical properties of wave height in an idealized square harbor with a partial opening are studied. The incident waves are propagated into the harbor numerically by the finite/infinite element method using three different wave models: (1) monochromatic wave train, (2) long-crested random wave train, and (3) short-crested random wave train. This study shows that for a given incident wave, the wave height in the harbor is affected by the wave model used. For long-term estimation of wave height exceedance probability, it is recommended that the waves be propagated into the harbor using the random wave model, and that wave heights be computed by use of the Rayleigh probability distribution.