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Influence of Reynolds Number on Multi-Objective Aerodynamic Design of a Wind Turbine Blade.

Ge M, Fang L, Tian D - PLoS ONE (2015)

Bottom Line: To make the study more general, two kinds of multi-objective optimization are involved: one is based on the maximum power coefficient (CPopt) and the ultimate load, and the other is based on the ultimate load and the annual energy production (AEP).It is found that under the same configuration, the optimal design has a larger CPopt or AEP (CPopt//AEP) for the same ultimate load, or a smaller load for the same CPopt//AEP at higher Reynolds number.At a certain tip-speed ratio or ultimate load, the blade operating at higher Reynolds number should have a larger chord length and twist angle for the maximum Cpopt//AEP.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing, P. R. China.

ABSTRACT
At present, the radius of wind turbine rotors ranges from several meters to one hundred meters, or even more, which extends Reynolds number of the airfoil profile from the order of 105 to 107. Taking the blade for 3MW wind turbines as an example, the influence of Reynolds number on the aerodynamic design of a wind turbine blade is studied. To make the study more general, two kinds of multi-objective optimization are involved: one is based on the maximum power coefficient (CPopt) and the ultimate load, and the other is based on the ultimate load and the annual energy production (AEP). It is found that under the same configuration, the optimal design has a larger CPopt or AEP (CPopt//AEP) for the same ultimate load, or a smaller load for the same CPopt//AEP at higher Reynolds number. At a certain tip-speed ratio or ultimate load, the blade operating at higher Reynolds number should have a larger chord length and twist angle for the maximum Cpopt//AEP. If a wind turbine blade is designed by using an airfoil database with a mismatched Reynolds number from the actual one, both the load and Cpopt//AEP will be incorrectly estimated to some extent. In some cases, the assessment error attributed to Reynolds number is quite significant, which may bring unexpected risks to the earnings and safety of a wind power project.

No MeSH data available.


Related in: MedlinePlus

Distribution of Reynolds number along the blade length for four typical MW-class wind turbines [7].
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pone.0141848.g001: Distribution of Reynolds number along the blade length for four typical MW-class wind turbines [7].

Mentions: Currently, the business operations of wind power companies are mainly based on onshore MW-class wind turbines, such as 1.5MW, 2MW, and 3MW wind turbines. But driven by economic efficiency, there is a great demand for very large offshore wind turbines [1]. Recently, many types of 5MW-8MW wind turbines have been successfully designed and put into commercial operation around the world, such as the Repower 5MW wind turbine, Siemens 6-MW wind turbine, and the Vestas 8-MW wind turbine (V164). Many larger wind turbines are also at the preliminary design stage [2–4], such as the 10MW-class wind turbine supported by the National High Technology Research and Development Program of China, and the 20MW wind turbine being developed in Energy Research Centre of the Netherlands [5–6]. It can be clearly seen that large-scale wind turbines have become the development trend of wind power. At present, the radius of wind turbine rotors ranges from several meters to one hundred meters, or even more, which extends Reynolds number of the airfoil profile from the order of 105 to 107. Here, Reynolds number of the airfoil profile is defined as Re = Uc/ν, where, U is the relative velocity of airfoil profile, c is the chord length, and ν is the kinematic viscosity. Fig 1 shows the distribution of Reynolds number along blades for different MW-class wind turbines at the rated condition [7]. Taking the 12MW wind turbine that is in the preliminary design in United Power Company as an example, the blade is 100 meters long, corresponding to Reynolds number of around 1.3×107.


Influence of Reynolds Number on Multi-Objective Aerodynamic Design of a Wind Turbine Blade.

Ge M, Fang L, Tian D - PLoS ONE (2015)

Distribution of Reynolds number along the blade length for four typical MW-class wind turbines [7].
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4631510&req=5

pone.0141848.g001: Distribution of Reynolds number along the blade length for four typical MW-class wind turbines [7].
Mentions: Currently, the business operations of wind power companies are mainly based on onshore MW-class wind turbines, such as 1.5MW, 2MW, and 3MW wind turbines. But driven by economic efficiency, there is a great demand for very large offshore wind turbines [1]. Recently, many types of 5MW-8MW wind turbines have been successfully designed and put into commercial operation around the world, such as the Repower 5MW wind turbine, Siemens 6-MW wind turbine, and the Vestas 8-MW wind turbine (V164). Many larger wind turbines are also at the preliminary design stage [2–4], such as the 10MW-class wind turbine supported by the National High Technology Research and Development Program of China, and the 20MW wind turbine being developed in Energy Research Centre of the Netherlands [5–6]. It can be clearly seen that large-scale wind turbines have become the development trend of wind power. At present, the radius of wind turbine rotors ranges from several meters to one hundred meters, or even more, which extends Reynolds number of the airfoil profile from the order of 105 to 107. Here, Reynolds number of the airfoil profile is defined as Re = Uc/ν, where, U is the relative velocity of airfoil profile, c is the chord length, and ν is the kinematic viscosity. Fig 1 shows the distribution of Reynolds number along blades for different MW-class wind turbines at the rated condition [7]. Taking the 12MW wind turbine that is in the preliminary design in United Power Company as an example, the blade is 100 meters long, corresponding to Reynolds number of around 1.3×107.

Bottom Line: To make the study more general, two kinds of multi-objective optimization are involved: one is based on the maximum power coefficient (CPopt) and the ultimate load, and the other is based on the ultimate load and the annual energy production (AEP).It is found that under the same configuration, the optimal design has a larger CPopt or AEP (CPopt//AEP) for the same ultimate load, or a smaller load for the same CPopt//AEP at higher Reynolds number.At a certain tip-speed ratio or ultimate load, the blade operating at higher Reynolds number should have a larger chord length and twist angle for the maximum Cpopt//AEP.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing, P. R. China.

ABSTRACT
At present, the radius of wind turbine rotors ranges from several meters to one hundred meters, or even more, which extends Reynolds number of the airfoil profile from the order of 105 to 107. Taking the blade for 3MW wind turbines as an example, the influence of Reynolds number on the aerodynamic design of a wind turbine blade is studied. To make the study more general, two kinds of multi-objective optimization are involved: one is based on the maximum power coefficient (CPopt) and the ultimate load, and the other is based on the ultimate load and the annual energy production (AEP). It is found that under the same configuration, the optimal design has a larger CPopt or AEP (CPopt//AEP) for the same ultimate load, or a smaller load for the same CPopt//AEP at higher Reynolds number. At a certain tip-speed ratio or ultimate load, the blade operating at higher Reynolds number should have a larger chord length and twist angle for the maximum Cpopt//AEP. If a wind turbine blade is designed by using an airfoil database with a mismatched Reynolds number from the actual one, both the load and Cpopt//AEP will be incorrectly estimated to some extent. In some cases, the assessment error attributed to Reynolds number is quite significant, which may bring unexpected risks to the earnings and safety of a wind power project.

No MeSH data available.


Related in: MedlinePlus