The Study On The Influence Of Channels On Multi-directional Irregular Wave Propagation

Sea waves are multi-directional irregular waves.It is often difficult to determine how much influence the channel has on wave propagation when waves are incident at different angles or in different directions.Due to the refraction effect of the channel on the waves,it will cause damage to the hydraulic structures near the edge of the channel.The design of the port channel and dredging project must consider the influence of the channel on the wave propagation,so as to reduce the mistakes in the overall layout of the project and avoid the destruction of the construction of the port area.Changes in the parameters of the channel will also affect the propagation of waves inside and outside the channel.How to comprehensively consider the influence of wave changes caused by the channel on the wave propagation inside and outside the channel becomes a key issue in the construction of the channel.In fact,the use of regular waves or unidirectional waves for engineering research and simulation is not representative.It is more practical to consider the influence of multi-directional irregular wave direction distribution in physical experiments and numerical simulations.The previous research mainly focused on the influence of the channel on the wave propagation considering the unidirectional wave action and analyzed the parameters around the channel.This paper will focus the effect of navigation channel on multi-directional wave propagation.First,the influence of the navigation channel on the idealized navigation channel under different conditions,the wave propagation under different terrains are compared.Further,the unidirectional and multi-directional waves with different incident angles,multi-directional irregular waves with different directional distributions and wave periods are numerically simulated.The content of the analysis highlights the difference between multi-directional waves and unidirectional waves,especially the influence of directional distribution.Finally,different conditions of water depths inside and outside the channel,different channel widths,side slopes are further considered.Based on the above-mentioned different situations,the influence of the channel on multi-directional wave propagation is analyzed and compared,the relevant conclusions are summarized.(1)The influence of the channel on the multi-directional irregular wave propagation is smaller than that of the unidirectional irregular wave.The higher the direction distribution concentration,the more obvious the refraction phenomenon of the wave propagation in the channel.(2)The refraction of the wave in channel will increase with the increase of the incidentangle of the wave;when the incident angle of the wave reaches a critical angle,the maximum relative wave height of the channel on the side reaches the peak value,and the refraction phenomenon is most obvious.The incident angle of the wave increase,and then the refraction of the waves by the channel will be weakened.The multi-directional wave with higher concentration of directional distribution,the refraction phenomenon is more obvious of.However,as the concentration of the direction distribution decreases,the wave energy is more evenly distributed in the direction,and the influence of the channel on the wave is also weakened.(3)The influence of the channel on the wave propagation inside and outside the channel mainly comes from the change of the water depth inside and outside the channel and the change of the wave incidence angle.The greater the water depth ratio inside and outside the channel,the greater the refraction of the wave in the channel.(4)The increase of the wave period,the widening of the channel width,and the steepening of the slope of the channel will enhance the refraction of the wave influenced by the channel.Since the direction distribution of the multi-directional wave homogenizes the influence of the channel on the wave,the multi-directional wave refraction is weaker than the unidirectional wave under the same condition.When the wave is incident at the critical incident angle,the above-mentioned influencing factors will be amplified.