Numerical Analysis Of The Wake And Interaction Effect Analysis For Tidal Arrays In The Tidal Farm

Tidal energy is a kind of renewable energy with most development potential.The technology of tidal energy power from offshore engineering prototype stagegradually enteres commercial application stage. A number of big tidal farm is in theplanning of construction, and the optimization of the layout of the tidal energyconversion device is one of the key links in the construction of tidal farm, whichdirectly related to the economic benefits of tidal farm. If the longitudinal spacebetween the tidal energy conversion devices is too small, along the direction flow,upstream units will produce wake effects to influence the downstream units,resulting in the output power of the downstream turbine decrease. In addition, due tothe turbulent fluid flow existing in the wake flow, turbine units may be damagedand working life reduced. So it needs according to the distribution of tidal energyresource, the characteristics and wake effect of turbine units, etc to optimize thelayout of the tidal farm. The paper studys the effect of upstream units to downstreamunits by combined the numerical simulation with the model test method, and studysdifferent layouts of the turbines. Specific research content are:First,the paper analyses the research status of the development and utilizationtechnology of tidal energy nationally and internationally. Then it summarizes thegeneral process of the echnology of tidal energy, which including model test, tidalenergy demonstration project and tidal farm. Clearing that studying the overallarrangement of the tidal turbines in the tidal farm is a inevitable trend.Second, using CFD software to proceed three-dimensional steady-statenumerical simulation for horizontal axis turbine, is to gain the graph of the wakecharacteristics including static pressure distribution, velocity distribution andvorticity distribution, and gain the research methods of the wake in tidal farm. Thenaccording to the calculation of fluid mechanics principle and the method ofnumerical calculation, to simulate two kind of arrangement longitudinal arrangement and staggered arrangement. It will comparative and analysis the distribution ofpressure, velocity, and turbulence in the flow field. And given the same flowstrength and direction, adjustment the longitudinal space between turbine units in therange form0to35D, is to get the thrust coefficients CT. And then arrival at aconclusion that the law of mutual influence turbine units under the two kinds of thearrangemen.Final, to conduct the flow field test of the turbine model, gets the data ofvelocity change in a single turbine model wake and in the flow field of many unitsunder the different layouts. And compared the data analysis results of the test andnumerical simulation results, is to further test and verify the conclusion of the CFDsoftware, but also to lay the foundation for the study of the next step engineeringapplication.