Combined Blade-Element Momentum—Lifting Line Model for Variable Loads on Downwind Turbine Towers
Downwind rotors are a promising concept for multi-megawatt scale large wind turbines due to their advantages in safety and cost reduction. However, they have risks from impulsive loads when one of the blades passes across the tower wake, where the wind speed is lower and locally turbulent. Although...
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| Format: | Article |
| Language: | English |
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MDPI AG
2018-09-01
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| Series: | Energies |
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| Online Access: | http://www.mdpi.com/1996-1073/11/10/2521 |
| _version_ | 1811278952772141056 |
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| author | Shigeo Yoshida |
| author_facet | Shigeo Yoshida |
| author_sort | Shigeo Yoshida |
| collection | DOAJ |
| description | Downwind rotors are a promising concept for multi-megawatt scale large wind turbines due to their advantages in safety and cost reduction. However, they have risks from impulsive loads when one of the blades passes across the tower wake, where the wind speed is lower and locally turbulent. Although the tower shadow effects on the tower loads have been discussed in former studies, there is currently no appropriate model for the blade-element and momentum theory so far. This study formulates the tower shadow effects on the tower load variation induced by blades using the lifting line theory, which does not require any empirical parameters. The method is verified via computational fluid dynamics for a 2 MW(megawatt), 3-bladed downwind turbine. The amplitude and the phase of the variation are shown to be accurate in outboard sections, where the rotor-tower clearance is large (>3.0 times of the tower diameter) and the ratio of the blade chord length is small (<0.5 times of the tower diameter), in both of rated and cut-out conditions. |
| first_indexed | 2024-04-13T00:44:57Z |
| format | Article |
| id | doaj.art-e4400c2e35cf44f1933a67e7533fe511 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-13T00:44:57Z |
| publishDate | 2018-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-e4400c2e35cf44f1933a67e7533fe5112022-12-22T03:10:03ZengMDPI AGEnergies1996-10732018-09-011110252110.3390/en11102521en11102521Combined Blade-Element Momentum—Lifting Line Model for Variable Loads on Downwind Turbine TowersShigeo Yoshida0Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, JapanDownwind rotors are a promising concept for multi-megawatt scale large wind turbines due to their advantages in safety and cost reduction. However, they have risks from impulsive loads when one of the blades passes across the tower wake, where the wind speed is lower and locally turbulent. Although the tower shadow effects on the tower loads have been discussed in former studies, there is currently no appropriate model for the blade-element and momentum theory so far. This study formulates the tower shadow effects on the tower load variation induced by blades using the lifting line theory, which does not require any empirical parameters. The method is verified via computational fluid dynamics for a 2 MW(megawatt), 3-bladed downwind turbine. The amplitude and the phase of the variation are shown to be accurate in outboard sections, where the rotor-tower clearance is large (>3.0 times of the tower diameter) and the ratio of the blade chord length is small (<0.5 times of the tower diameter), in both of rated and cut-out conditions.http://www.mdpi.com/1996-1073/11/10/2521wind turbinedownwindtower shadowblade-element momentumlifting line |
| spellingShingle | Shigeo Yoshida Combined Blade-Element Momentum—Lifting Line Model for Variable Loads on Downwind Turbine Towers Energies wind turbine downwind tower shadow blade-element momentum lifting line |
| title | Combined Blade-Element Momentum—Lifting Line Model for Variable Loads on Downwind Turbine Towers |
| title_full | Combined Blade-Element Momentum—Lifting Line Model for Variable Loads on Downwind Turbine Towers |
| title_fullStr | Combined Blade-Element Momentum—Lifting Line Model for Variable Loads on Downwind Turbine Towers |
| title_full_unstemmed | Combined Blade-Element Momentum—Lifting Line Model for Variable Loads on Downwind Turbine Towers |
| title_short | Combined Blade-Element Momentum—Lifting Line Model for Variable Loads on Downwind Turbine Towers |
| title_sort | combined blade element momentum lifting line model for variable loads on downwind turbine towers |
| topic | wind turbine downwind tower shadow blade-element momentum lifting line |
| url | http://www.mdpi.com/1996-1073/11/10/2521 |
| work_keys_str_mv | AT shigeoyoshida combinedbladeelementmomentumliftinglinemodelforvariableloadsondownwindturbinetowers |