The roughness increase on horizontal axis wind turbine(HAWT) blade surface,especially on the leading edge,can lead to an aerodynamic performance degradation of blade and power output loss of HAWT,so roughness sensitiv...The roughness increase on horizontal axis wind turbine(HAWT) blade surface,especially on the leading edge,can lead to an aerodynamic performance degradation of blade and power output loss of HAWT,so roughness sensitivity is an important factor for the HAWT blade design.However,there is no criterion for evaluating roughness sensitivity of blade currently.In this paper,the performance influences of airfoil aerodynamic parameters were analyzed by the blade element momentum(BEM) method and 1.5 MW wind turbine blade.It showed that airfoil lift coefficient was the key parameter to the power output and axial thrust of HAWT.Moreover,the evaluation indicators of roughness sensitivity for the different spanwise airfoils of the pitch-regulated HAWT blade were proposed.Those respectively were the lift-to-drag ratio and lift coefficient without feedback system,the maximum lift-to-drag ratio and design lift coefficient with feedback system for the airfoils at outboard section of blade,and lift coefficient without feedback,maximum lift coefficient with feedback for the airfoils at other sections under the pitch-fixed and variable-speed operation.It is not necessary to consider the roughness when HWAT can be regulated to the rated power output by the pitch-regulated and invariable-speed operation.展开更多
The effect of surface roughness on the boundary development and loss behavior of turbine blades is investigated with different Reynolds numbers in this paper.The result shows that the velocity profile in boundary laye...The effect of surface roughness on the boundary development and loss behavior of turbine blades is investigated with different Reynolds numbers in this paper.The result shows that the velocity profile in boundary layer is plumper on rough surface than on smooth blade.The aerodynamic loss is lowered at low Reynolds number,but becomes significantly large at high Reynolds number.The total pressure loss coefficient of cascade can reach a top increase of 129%for rougher blades comparing with smooth blades at Re=300000.展开更多
The focus of this research was on the equivalent particle roughness height correction required to account for the presence of ice when determining the performances of wind turbines.In particular,two icing processes(fr...The focus of this research was on the equivalent particle roughness height correction required to account for the presence of ice when determining the performances of wind turbines.In particular,two icing processes(frost ice and clear ice)were examined by combining the FENSAP-ICE and FLUENT analysis tools.The ice type on the blade surfaces was predicted by using a multi-time step method.Accordingly,the influence of variations in icing shape and ice surface roughness on the aerodynamic performance of blades during frost ice formation or clear ice formation was investigated.The results indicate that differences in blade surface roughness and heat flux lead to disparities in both ice formation rate and shape between frost ice and clear ice.Clear ice has a greater impact on aerodynamics compared to frost ice,while frost ice is significantly influenced by the roughness of its icy surface.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 50976117 and 50836006)
文摘The roughness increase on horizontal axis wind turbine(HAWT) blade surface,especially on the leading edge,can lead to an aerodynamic performance degradation of blade and power output loss of HAWT,so roughness sensitivity is an important factor for the HAWT blade design.However,there is no criterion for evaluating roughness sensitivity of blade currently.In this paper,the performance influences of airfoil aerodynamic parameters were analyzed by the blade element momentum(BEM) method and 1.5 MW wind turbine blade.It showed that airfoil lift coefficient was the key parameter to the power output and axial thrust of HAWT.Moreover,the evaluation indicators of roughness sensitivity for the different spanwise airfoils of the pitch-regulated HAWT blade were proposed.Those respectively were the lift-to-drag ratio and lift coefficient without feedback system,the maximum lift-to-drag ratio and design lift coefficient with feedback system for the airfoils at outboard section of blade,and lift coefficient without feedback,maximum lift coefficient with feedback for the airfoils at other sections under the pitch-fixed and variable-speed operation.It is not necessary to consider the roughness when HWAT can be regulated to the rated power output by the pitch-regulated and invariable-speed operation.
文摘The effect of surface roughness on the boundary development and loss behavior of turbine blades is investigated with different Reynolds numbers in this paper.The result shows that the velocity profile in boundary layer is plumper on rough surface than on smooth blade.The aerodynamic loss is lowered at low Reynolds number,but becomes significantly large at high Reynolds number.The total pressure loss coefficient of cascade can reach a top increase of 129%for rougher blades comparing with smooth blades at Re=300000.
基金Natural Science Foundation of Liaoning Province(2022-MS-305)Foundation of Liaoning Province Education Administration(LJKZ1108).
文摘The focus of this research was on the equivalent particle roughness height correction required to account for the presence of ice when determining the performances of wind turbines.In particular,two icing processes(frost ice and clear ice)were examined by combining the FENSAP-ICE and FLUENT analysis tools.The ice type on the blade surfaces was predicted by using a multi-time step method.Accordingly,the influence of variations in icing shape and ice surface roughness on the aerodynamic performance of blades during frost ice formation or clear ice formation was investigated.The results indicate that differences in blade surface roughness and heat flux lead to disparities in both ice formation rate and shape between frost ice and clear ice.Clear ice has a greater impact on aerodynamics compared to frost ice,while frost ice is significantly influenced by the roughness of its icy surface.
