A Study on Aerodynamic Performance of Diff erent Bionic-Structured Surfaces via Belt Grinding

The structural characteristics of the surfaces of sharkskin have great influence on their aerodynamic performance.It has been proved that the sharkskin’s ribbed structure can improve the aerodynamic performance of the parts up to 10%.At present,the main processing methods for this structure are laser,rolling,etc.,which have low efficiency and poor surface integrity.Belt grinding is widely used in the surface grinding and polishing.It plays an important role in improving the surface integrity and can realize the micro-structure machining at the same time.To achieve drag reduction,based on the characteristics of drag reduction of Bionic-Ribbed Structures(BRS),diff erent BRS(V,trapezoid and wave)on a blade were processed and studied.First,this paper introduces the theory of drag reduction induced by BRS and processing methods of diff erent BRS on a blade by belt grinding,and carried out the verification of the belt-grinding methods.Then,diff erent BRS models were established on the blade with diff erent tip angles,and the aerodynamic performance was analyzed through simulation.It was found that the low-velocity layer near the BRS decreased when tip angle increased.Its wall shear stress also increased and tip angle of 45o had the best performance regardless of which BRS was.Some suggestions were given for belt grinding.The velocity along height from valley of BRS and velocity streamline was demonstrated.Secondary vortex was observed.Velocity gradient and vortex were the main reasons for the diff erence of wall shear stress.