Numerical Simulation Of The Response Relationship Between The Tidal Energy Flux And Runoff In Liaohe River Estuary

Estuaries, as the most sensitive region of land-ocean interaction, are affected byboth tide and runoff. The transport process of pollutants, sediment, salinity intrusionand energy transfer all have significant impact on estuarine water environment,coastal engineering and topography evolution. The energy reserves and tidal energytransfer rules in estuaries are always concerned in the research of dynamic sediment,tidal energy development and water exchange capacity. Therefore, the research of thetidal energy flux distribution in Liaohe River Estuary influenced by tide dynamic andrunoff could provide references to some study like estuarine dynamic sedimentationethics or so.The hydrodynamic field for Liaohe River Estuary is simulated based on FVCOM,and then the tidal energy flux and tidal energy dissipation are calculated, so that thedynamics process in the estuary can be learned from the angle of the tidal energy.Firstly, validate the model accuracy according to the observed water level and tidalcurrent datum of Liaohe River Estuary in2011and2009, and analyze the tidal wavecharacteristics of M₂、S₂、K₁、O₁. Furthermore, discuss the tidal current characteristicscombine with the persistency R of current and meanwhile point out that the currentpersistency is better in the river section and the tidal flat of Gaizhoutan near the mouth.Secondly, based on the hydrodynamic model, the response relationship between thetidal energy flux and runoff in Liaohe River Estuary is studied. Besides, the tidalenergy flux and tidal dissipation in Shuangtaizi River Estuary are compared withDaliaohe River Estuary. Thirdly, take Daliaohe River Estuary as research area, extendthe river upstream to Sanchahe, which is the tidal current limit, to explore therelationship between water depth, tidal range and tidal energy.The research shows that the tidal energy distribution affected by both tide andrunoff is various around the mouth and the river section. The average value of tidalenergy flux during spring tide is almost double that during the neap tide. The tidal energy flux at dry season has the farthest impact during the tidal energy transmissionprocess and has the highest value overall. The high energy regions are concentrated inthe southeast of Gaizhoutan and narrow deep channels or turns, and low energyregions are mainly in tidal flat near the mouth and the upper reach. It is the shape ofriverway that decides the characteristics of tidal energy flux and tidal energydissipation, and the spatial distribution of the kinetic energy has the same distributionwith water depth, while the potential energy in space is consistent with tidal range andoccupies the main part in the energy along the river.In Shuangtaizi River Estuary, tidal energy dissipation increases with the increaseof runoff, and the maximum value of energy dissipation rate is0.13MW·km-2at floodseason. In Daliaohe River Estuary, the energy dissipation rate during spring tide isapproximately double the value during neap tide. The curving degree of ShuangtaiziRiver Estuary is less than Daliaohe River Estuary while the width-depth ratio isgreater than Daliaohe River Estuary, which results in the tidal energy flux in crosssection areas in Shuangtaizi River Estuary greater than that in Daliaohe River Estuary.In the river mouth, the direction of the tidal energy flux is point to the sea at floodseason while opposite at dry season.The tidal energy flux distributions of M2tidal constituent at four representativetime show that the tidal energy flux around the bend of estuary has a higher value atthe maximum flood tide, and at high tide the tidal energy flux distribution is moreuniform and its value is higher at the bend while the value is lower in the midsectionat low tide. At the maximum ebb tide, the tidal energy flux has a higher value in theupstream and downstream near the mouth while the value is lower in the midsection.The maximum value of tidal energy flux in the river section generally always occursat the first corner in the Daliaohe River Estuary.