Design And Hydrodynamic Analysis Of Suspending Horizontal Axial Tidal Current Turbine And Fairing

In modern society,the demand for energy is growing,while due to the drying up of traditional energy and the deteriorating environment,all countries of the world transfer their attention to renewable energy sources.Due to the features of excellent environmental protection property,renewability,and rich reservation of tidal current energy,it has become the research emphasis.Overseas research on tidal current power generation technology started early and developed relatively mature,especially in some developed countries in Europe,there have been engineering examples of large-scale commercial application,which can provide some references for the research and development of tidal current power technology in China.After the summary on the development status and technological difficulty of tidal current energy generator at home and abroad in recent years,in this thesis,it puts forward a new suspended two-way tidal current generator,and has design and research on its key position,while the specific contents include:With direct-drive generation design scheme,the motor and impeller are connected by the key directly,and the rotation of impeller can drive the motor rotor directly;the motor adopts the design with less number of slots and multiple mode;besides,the motor side hood is designed into “bullet” bypass cap to stabilize the flow field and reduce the flow resistance;Based on BEM theory and airfoil theory,it designs a reversible impeller.After the selection of basic airfoil profile,then by means of intercepting and matching,it can get new S airfoil profile,later,it shall confirm the design parameter of blade,gets the shape of every cross section by means of Wilson,and then induces it into CATIA for modeling after the transformation of coordinates.By means of Fluent simulation,it can analyze the influence of blade of different quantity to the hydrodynamic performance of impeller,and then it gets the conclusion that the generator with four blades has the best effect;On the basis of the design principle of fairing and principle of wind diffuser,itdesigns a bilateral symmetrical folding fairing.After the selection of the best optimized angle of flaring,25°,it has optimized design on the length of flaring section,and after the simulated analysis on the different lengths of flaring section by means of Fluent,it can gets the conclusion that the length of 220 mm has the best effect;By means of flume experiment,it testifies that impeller has comparatively good performance of bilateral capacitation;when the electrical engineer is at the comparatively low flow velocity(0.5m/s),it can guarantee normal operation,when the turbine is at the comparatively low flow velocity(0.5m/s),it can guarantee normal operation,and when the output power of impeller is 2m/s,it can reach to the rated power,40 W,when it has the largest efficiency of capacitation,which is 25.4%.Above all,this device can provide some references for the later sea trial and practical application in the future.