This paper aims to design an optimized blade for Horizontal Axis Wind Turbine(HWAT).Since airfoil is a basic component of blade design,an optimized airfoil(referred as SJX)was proposed based on the line theory through...This paper aims to design an optimized blade for Horizontal Axis Wind Turbine(HWAT).Since airfoil is a basic component of blade design,an optimized airfoil(referred as SJX)was proposed based on the line theory through the weight analogy to pressure distribution of air flow.Its lift,drag,lift⁃to⁃drag ratio were compared with those NACA2409⁃34,NACA2410,and RK40 airfoils by using Profili software at fixed wind velocity and under different angles of attack.The NACA2409⁃34 airfoil was found to be greatly similar with the SJX airfoil.Based on the Wilson method,blades using SJX and NACA2490⁃34 airfoils were developed and different performance parameters such as velocity distribution,pressure distribution,and power were compared under variable wind velocities and different angles of attack ranging from-4°to 6°at different radius from the center of rotor using computational fluid dynamics(CFD)in ANSYS FLUENT.Results of the study suggested that the performance of the SJX based airfoil and blade was much more optimized.展开更多
Using transverse steps is one of the adopted strategies to improve the hydrodynamic characteristics of planing crafts.In the present paper,hydrodynamic characteristics of stepped planing crafts are numerically investi...Using transverse steps is one of the adopted strategies to improve the hydrodynamic characteristics of planing crafts.In the present paper,hydrodynamic characteristics of stepped planing crafts are numerically investigated.For this purpose,we analyzed the effects of five different types of transverse steps on lift to drag ratio,resistance,trim angle and sinkage of high speed planing crafts.Contours of pressure distribution on the bottom of crafts,water volume fraction and free-surface are also presented at different hull velocities.Computed numerical results are properly validated against our conducted towing tank experimental tests.展开更多
文摘This paper aims to design an optimized blade for Horizontal Axis Wind Turbine(HWAT).Since airfoil is a basic component of blade design,an optimized airfoil(referred as SJX)was proposed based on the line theory through the weight analogy to pressure distribution of air flow.Its lift,drag,lift⁃to⁃drag ratio were compared with those NACA2409⁃34,NACA2410,and RK40 airfoils by using Profili software at fixed wind velocity and under different angles of attack.The NACA2409⁃34 airfoil was found to be greatly similar with the SJX airfoil.Based on the Wilson method,blades using SJX and NACA2490⁃34 airfoils were developed and different performance parameters such as velocity distribution,pressure distribution,and power were compared under variable wind velocities and different angles of attack ranging from-4°to 6°at different radius from the center of rotor using computational fluid dynamics(CFD)in ANSYS FLUENT.Results of the study suggested that the performance of the SJX based airfoil and blade was much more optimized.
文摘Using transverse steps is one of the adopted strategies to improve the hydrodynamic characteristics of planing crafts.In the present paper,hydrodynamic characteristics of stepped planing crafts are numerically investigated.For this purpose,we analyzed the effects of five different types of transverse steps on lift to drag ratio,resistance,trim angle and sinkage of high speed planing crafts.Contours of pressure distribution on the bottom of crafts,water volume fraction and free-surface are also presented at different hull velocities.Computed numerical results are properly validated against our conducted towing tank experimental tests.