Wind Tunnel Test And Numerical Simulation Study On Icing Of Horizontal Axis Wind Turbines

In recent years,with the increase in the number of wind turbines installed,the issue of wind turbines operating under harsh conditions has become an important research topic.The icing of wind turbines in severe cold conditions can lead to a decrease in their power generation efficiency,so it is very important to study the icing of wind turbine blades.The numerical simulation method of FENSAP-ICE icing in the simulation software ANSYS was studied,and the calculation method of exposed ice was optimized to make the formed angular ice more accurate.The numerical simulation method was verified through experiments,and the wind turbine blades were numerically simulated and analyzed.The main content and conclusions of the study are as follows:(1)Ice tests were conducted on the NACA0018 symmetric airfoil and NACA4415 asymmetric airfoil using an icing wind tunnel.The uniformity of the wind tunnel flow field,temperature uniformity,and stability were first calibrated,and then ice profiles of different airfoils at different temperatures and times were produced using the wind tunnel.(2)Using FENSAP-ICE for numerical simulation,the commonly used one-step icing method in FENSAP-ICE is compared with the layered icing method proposed in this thesis.Using the NACA0018 symmetric airfoil and NACA4415 asymmetric airfoil as models,based on the above experimental results,it is found that the ice formed at low temperatures and low wind speeds and high temperatures is streamlined ice,using a one-step icing method;Under high wind speed and high temperature,layered ice forms angular ice and conforms to the experimental ice type.Four layers of calculation method are selected and 600000 grids are selected for calculation.(3)Firstly,the wind turbine blades were rotated to form ice,which is not easy to form angular ice.Then,the three-dimensional blades were divided into twodimensional airfoils using blade element theory for calculation.Perform numerical simulation of blade icing according to the proposed operating conditions and analyze the calculation results.The icing type at -4℃ is basically angular ice,and that at -12℃is basically streamline ice.The growth of ice formation at -4℃ becomes slow after 60 minutes,while it continues to increase at -12℃.The freezing limit at -4℃ increases with the increase of liquid water content,while the freezing limit at -12℃ is relatively stable with liquid water content,and the freezing thickness is opposite;As the diameter of water droplet particles increases,the freezing limit and freezing thickness at both temperatures increase.The change in freezing limit at -4℃ is greater,while the change in freezing thickness at -12℃ is greater.The numerical simulation and calculation method of wind turbine icing in this thesis provide a reference for subsequent analysis of wind turbine blade icing,and provide a foundation for wind turbine blade deicing work.