Design And Numerical Simulation Of Motional Module For Oscillatory-type Tidal Current Power Generation System

With the aggravated fossil crisis and environmental pollution,clean energy utilization has beenfocus of the research on new energy.As asignificant part of clean energy,marine energy has been greatly developed in recent years.And because of theabundantresource and high energy efficiency,the development of tidal current generation technology has been paid great attention.Aimingat optimizing the oscillatory-type foiland fluid induced motion type tidal current generation systems,CFD methods and simulation software were also used for numerical calculation of the motional module to improve the lift coefficient and system generating efficiency.As for simulation design of the oscillatory-type foil tidal current power generation system,elastic material was utilized instead of rigid material to build the geometric models of the foil motional models.Influence of the elastic material on the lift coefficientwas explored by means of fluid-solid interactionsimulation.The simulation results of oscillatory-type foil tidal current power generation system showed that the elastic deformation happened while elastic foil vibrated in the fluidand led to changes in lift coefficient.When elastic coefficient E was 10~8~10~6,the lift coefficient raised with the decrease of the elastic coefficient.When continued to decrease to 50000,the lift coefficient decreased.Elastic coefficient for the optimum lift coefficient was 10~6.Therefore,the elastic material had a great effect on the lift coefficient of foil,and theoptimum material elastic coefficientE was10~6.As for simulation design of the fluid induced motion type tidal current power generation system,7 types and 11 geometric models of motional modules were established.The simulation operation is carried out using the two-dimensional fluid calculation and fluid-solid interaction calculation methods.Results of the two-dimensional fluid calculation showed that the lift of periodic changecould be obtained byevery model,but a flat head model of the forepart was more ideal;It was also found that the lift coefficient increased with the length of x-axis direction and increase in length of the model affect the system periodicity,causing instability of lift coefficient.Therefore,The 0.15 m x direction extension model had the obvious advantages in lift coefficient and periodicity.The fluid-solid interaction calculation resultshowed that the model could realize reciprocating motion,the amplitude of motion was proportional to the length of the model,but with the length increased,amplitude appeared irregular vibration.The peak lift coefficient of the 0.15 m x direction extension model was 8.8,and the lift coefficient increased by 185% compared withthe semi-circle model.the 0.15 m x direction extension model was the optimum model.