HAWT Aerodynamic Performance Prediction Using a Semi-Rigid Wake Model Based on Vortex Theory

2000 ◽  
Vol 24 (5) ◽  
pp. 349-359
Author(s):  
Ye Zhiquan ◽  
Chen Yan ◽  
Zhang Feng
2021 ◽  
Vol 2083 (4) ◽  
pp. 042005
Author(s):  
Xueyi Liu ◽  
Junhao Dong ◽  
Guangyu Tu

Abstract Fan, as the most commonly used mechanical equipment, is widely used. In order to solve the problem of fan bearing fault diagnosis, this paper analyzes the main factors affecting fan spindle speed and power generation in operation. The input and output parameters of the performance prediction model are determined. The performance prediction model of wind turbine is established by using generalized regression neural network, and the smoothing factor of GRNN is optimized by comparing the prediction accuracy of the model. Based on this model, the sliding data window method is used to calculate the residual evaluation index of wind turbine speed and power in real time. When the evaluation index continuously exceeds the pre-set threshold, the abnormal state of wind turbine can be judged. In order to obtain wind turbine blades with better aerodynamic performance, a blade aerodynamic performance optimization method based on quantum heredity is proposed. The B é zier curve control point is used as the design variable to represent the continuous chord length and torsion angle distribution of the blade, the blade shape optimization model aiming at the maximum power is established, and the quantum genetic algorithm is used to optimize the chord length and torsion angle of the blade under different constraints. The optimization results of quantum genetic algorithm and classical genetic algorithm are compared and analyzed. Under the same parameters and boundary conditions, the proposed blade aerodynamic optimization method based on quantum genetic optimization is better than the classical genetic optimization method, and can obtain better blade aerodynamic shape and higher wind energy capture efficiency. This method makes up for the shortcomings of traditional fault diagnosis methods, improves the recognition rate of fault types and the accuracy of fault diagnosis, and the diagnosis effect is good.


1980 ◽  
Vol 24 (04) ◽  
pp. 227-231
Author(s):  
Gilbert Dyne

Problems associated with the design of wake-adapted propellers are illustrated by results obtained from a simple propeller and wake model. It is shown that the widely used approach of the vortex theory gives much-too-low induced axial velocities at the inner radii of the propeller, which results in too-low blade pitch ratios. The reason for this is that no regard is paid to the fact that the vorticity of the approaching flow is changed by the propeller. If this changing vorticity is introduced in the vortex theory, its shortcomings are eliminated. An effect of the improvement is that the effective wake at the propeller plane differs from the nominal wake. The difference depends upon the propeller load. The propeller is shown to have a leveling effect on a nonuniform axisymmetric nominal wake.


Author(s):  
Saba Batool ◽  
Junaid Rashid ◽  
Muhammad Wasif Nisar ◽  
Jungeun Kim ◽  
Toqeer Mahmood ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document