Interaction between heterogeneous thermal stratification and wakes of wind turbine arrays
Abstract The thermal heterogeneity between the land and sea might affect the wind patterns within wind farms (WF) located near seashores. This condition was modeled with a large‐eddy simulation of a numerical weather prediction model (Weather Research and Forecasting) that included the wind turbine...
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| Format: | Article |
| Language: | English |
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Wiley
2023-02-01
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| Series: | Wind Energy |
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| Online Access: | https://doi.org/10.1002/we.2792 |
| _version_ | 1797955233443217408 |
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| author | Keisuke Nakao Yasuo Hattori |
| author_facet | Keisuke Nakao Yasuo Hattori |
| author_sort | Keisuke Nakao |
| collection | DOAJ |
| description | Abstract The thermal heterogeneity between the land and sea might affect the wind patterns within wind farms (WF) located near seashores. This condition was modeled with a large‐eddy simulation of a numerical weather prediction model (Weather Research and Forecasting) that included the wind turbine actuator disk model (ADM). The assumed condition was that the downstream surface temperature was relatively higher (unstably stratified condition) than the neutrally stratified upstream wind. Under this condition, a thermal internal boundary layer (TIBL) was developed from an area where a step‐changed surface temperature was implemented. The combined effect of the wake deficit due to the WF and velocity recovery as a result of enhanced mixing under unstable stratification showed significant modulation of the wind speed at the hub height when local atmospheric stability affected the wind turbine (WT). We show that TIBL height depends on the variables to be evaluated as the threshold. A precise prediction of the TIBL height is beneficial for better estimation of power generation. A prediction model was proposed as an extension of the internal boundary layer (IBL) model for neutral stratification, and the results tracked TIBL development reasonably well. The effects of WFs on surface properties (e.g., friction velocity, heat flux, and Obukhov length) and the tendency of IBL growth were minor. A single WT wake was also assessed under several TIBL developmental stages (i.e., location) and thermal stratification conditions. The standard deviation of the wake deficit increased vertically during the development stage of the TIBL. In contrast, the coefficients in the horizontal and vertical directions were comparable when the WT was deep inside the TIBL. |
| first_indexed | 2024-04-10T23:30:01Z |
| format | Article |
| id | doaj.art-befa2d7c34494910bbf91c6af8153f14 |
| institution | Directory Open Access Journal |
| issn | 1095-4244 1099-1824 |
| language | English |
| last_indexed | 2024-04-10T23:30:01Z |
| publishDate | 2023-02-01 |
| publisher | Wiley |
| record_format | Article |
| series | Wind Energy |
| spelling | doaj.art-befa2d7c34494910bbf91c6af8153f142023-01-12T07:11:10ZengWileyWind Energy1095-42441099-18242023-02-0126216318110.1002/we.2792Interaction between heterogeneous thermal stratification and wakes of wind turbine arraysKeisuke Nakao0Yasuo Hattori1Sustainable System Research Laboratory, Meteorology and Fluid Science Division Central Research Institute of Electric Power Industry Chiba JapanSustainable System Research Laboratory, Meteorology and Fluid Science Division Central Research Institute of Electric Power Industry Chiba JapanAbstract The thermal heterogeneity between the land and sea might affect the wind patterns within wind farms (WF) located near seashores. This condition was modeled with a large‐eddy simulation of a numerical weather prediction model (Weather Research and Forecasting) that included the wind turbine actuator disk model (ADM). The assumed condition was that the downstream surface temperature was relatively higher (unstably stratified condition) than the neutrally stratified upstream wind. Under this condition, a thermal internal boundary layer (TIBL) was developed from an area where a step‐changed surface temperature was implemented. The combined effect of the wake deficit due to the WF and velocity recovery as a result of enhanced mixing under unstable stratification showed significant modulation of the wind speed at the hub height when local atmospheric stability affected the wind turbine (WT). We show that TIBL height depends on the variables to be evaluated as the threshold. A precise prediction of the TIBL height is beneficial for better estimation of power generation. A prediction model was proposed as an extension of the internal boundary layer (IBL) model for neutral stratification, and the results tracked TIBL development reasonably well. The effects of WFs on surface properties (e.g., friction velocity, heat flux, and Obukhov length) and the tendency of IBL growth were minor. A single WT wake was also assessed under several TIBL developmental stages (i.e., location) and thermal stratification conditions. The standard deviation of the wake deficit increased vertically during the development stage of the TIBL. In contrast, the coefficients in the horizontal and vertical directions were comparable when the WT was deep inside the TIBL.https://doi.org/10.1002/we.2792internal boundary layerlarge‐eddy simulationthermal heterogeneityweather research and forecasting modelwind turbine wake |
| spellingShingle | Keisuke Nakao Yasuo Hattori Interaction between heterogeneous thermal stratification and wakes of wind turbine arrays Wind Energy internal boundary layer large‐eddy simulation thermal heterogeneity weather research and forecasting model wind turbine wake |
| title | Interaction between heterogeneous thermal stratification and wakes of wind turbine arrays |
| title_full | Interaction between heterogeneous thermal stratification and wakes of wind turbine arrays |
| title_fullStr | Interaction between heterogeneous thermal stratification and wakes of wind turbine arrays |
| title_full_unstemmed | Interaction between heterogeneous thermal stratification and wakes of wind turbine arrays |
| title_short | Interaction between heterogeneous thermal stratification and wakes of wind turbine arrays |
| title_sort | interaction between heterogeneous thermal stratification and wakes of wind turbine arrays |
| topic | internal boundary layer large‐eddy simulation thermal heterogeneity weather research and forecasting model wind turbine wake |
| url | https://doi.org/10.1002/we.2792 |
| work_keys_str_mv | AT keisukenakao interactionbetweenheterogeneousthermalstratificationandwakesofwindturbinearrays AT yasuohattori interactionbetweenheterogeneousthermalstratificationandwakesofwindturbinearrays |