| Scale effect on the open water performance of the propeller is significant to propeller design.The study of propeller scale effect will help to further explore the difference between the hydrodynamic performances of model-scale and full-scale propellers,so that it is possible to more accurately modify the scale effect and provide a more solid theoretical basis for propeller design.Simulations of propeller E1619 of two models with different scales are presented using structural grids and an in-house numerical code HUST-SHIP for the purpose of analyzing the scale effect on propellers.A verification study was performed on different grids,time sizes and inner steps.Propeller open water performance at given advance coefficient was obtained,showing obvious increase on KT,KQ and0 in big models.The structure of tip vortex is shown and compared by displaying iso-surface of the positive second invariant.Pressure coefficient paring is observed on the blade surfaces and the sections of 0.25R,0.5R,0.75R and R.The pressure coefficients of different propellers show high similarity but are of different peak and valley values.The fluid axial velocities on the plane where y=0 are compared to describe the difference among the propellers with different scales.Axial velocities on the plane where x=0.17D is displayed and the average,variance and unevenness values are compared to study the similarities and differences among different propellers. |
