Predictions of ice formations on wind turbine blades and power production losses due to icing

Abstract

Prediction of ice shapes on a wind turbine blade makes it possible to estimate the power production losses due to icing. Ice accretion on wind turbine blades is responsible for a significant increase in aerodynamic drag and decrease in aerodynamic lift and may even cause premature flow separation. All these events create power losses and the amount of power loss depends on the severity of icing and the turbine blade profile. The role of critical parameters such as wind speed, temperature, liquid water content on the ice shape, and size is analyzed using an ice accretion prediction methodology coupled with a blade element momentum tool. The predicted ice shapes on various airfoil profiles are validated against the available experimental and numerical data in the literature. The error in predicted rime and glime ice volumes and the maximum ice thicknesses varies between 3% and 25% in comparison with the experimental data depending on the ice type. The current study presents an efficient and accurate numerical methodology to perform an investigation for ice-induced power losses under various icing conditions on horizontal axis wind turbines. The novelty of the present work resides in a unified and coupled approach that deals with the ice accretion prediction and performance analysis of iced wind turbines. Sectional ice profiles are first predicted along the blade span, where the concurrence of both rime and glaze ice formations may be observed. The power loss is then evaluated under the varying ice profiles along the blade. It is shown that the tool developed may effectively be used in the prediction of power production losses of wind turbines at representative atmospheric icing conditions. KEYWORDS atmospheric icing, ice accretion, power losses, wind energy INTRODUCTIONIn recent years, producing energy from renewable energy sources is in great demand and installation of wind turbines in the world has been increasing steadily. Cold climate regions have the advantage of high wind speeds, high air density, and sparsely populated residential areas.However, wind turbines in these regions are usually exposed to atmospheric icing conditions, which have a detrimental effect on the performance.Formation of ice on wind turbine blades creates unwanted performance losses by changing blade aerodynamic characteristics and also reduces the lifetime of wind turbine components. 1,2 It is well-known that icing occurs when supercooled droplets in the atmosphere impinge on a surface such as a turbine blade. Liquid water content, temperature, droplet diameter, and wind speed are the basic factors affecting icing. Liquid water content mostly determines the severity of icing and its type. Wind speed and temperature also influence the type and intensity of ice. Droplets may either freeze instantly and form rime

Droplet Impact on the Cold Elastic Superhydrophobic Membrane with Low Ice Adhesion

“…Ice accumulation is a common and serious phenomenon that exists in numerous industrial fields such as electricity transportation, wind turbine and air conditioning [1][2][3]. The ice accretion may cause the failure of conductors, decrease the efficiency of air conditioning and even cause the system shutdown, which would pose a huge energy consumption and potential safety hazard [4,5]. Therefore, developing an effective and reliable method to reduce ice accumulation is of great practical importance.…”

Isogeometric analysis of ice accretion on wind turbine blades

“…Wind turbine blade ice accretion, which occurs primarily near the leading edge, has demonstrated negative effects on blade performance, including reduced power outputs, surface erosion, and sudden blade failures and damage [2]. The aerodynamic impact of ice accretion, particularly related to changes in the airfoil and blade geometries due to ice formation, has been widely studied in correlation with wind turbine performance and power outputs [3][4][5][6][7][8][9][10][11][12][13][14]. A number of recent studies have also experimentally investigated the progression of ice accretion on wind turbine airfoils, including changes in the shape, distribution, and properties of ice that occur during this process [15,16].…”

Aerodynamics of an airfoil with leading‐edge icing

“…To maintain the rotation of a vertical axis rotating rig, Han et al 5 found that the torque requirement increased 70% under severe icing conditions. Recently, Yirtici et al 6 predicted 17% power loss for a NREL 5‐MW wind turbine during icing conditions. In addition, icing on the airfoil leads to measurement errors due to ice accretion on sensors and increased mechanical loads, which can ultimately lead to mechanical failures, electrical failures, changes in material properties and safety issues related to ice being thrown from the rotor blades 7 .…”

“…The geometry of the contaminations agrees qualitatively well with ice geometries found in the literature. 6,8,15 However, ice feathers or rivulets located downstream of the leading edge are not present in the geometries used in the present study. The type C contamination geometry is horn-like.…”