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Raine, Nigel. "Postcode average wind speed indicator". Weather 65, n.º 9 (25 de agosto de 2010): 252. http://dx.doi.org/10.1002/wea.639.
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Lee, Chee-Cheong y Soo-Hong Park. "Computational Methods of Average Wind Speed and Direction". Journal of information and communication convergence engineering 8, n.º 1 (28 de febrero de 2010): 29–34. http://dx.doi.org/10.6109/jicce.2010.8.1.029.
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Nolan, David S., Jun A. Zhang y Eric W. Uhlhorn. "On the Limits of Estimating the Maximum Wind Speeds in Hurricanes". Monthly Weather Review 142, n.º 8 (1 de agosto de 2014): 2814–37. http://dx.doi.org/10.1175/mwr-d-13-00337.1.
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Abstract This study uses an observing system simulation experiment (OSSE) approach to test the limitations of even nearly ideal observing systems to capture the peak wind speed occurring within a tropical storm or hurricane. The dataset is provided by a 1-km resolution simulation of an Atlantic hurricane with surface wind speeds saved every 10 s. An optimal observing system consisting of a dense field of anemometers provides perfect measurements of the peak 1-min wind speed as well as the average peak wind speed. Suboptimal observing systems consisting of a small number of anemometers are sampled and compared to the truth provided by the optimal observing system. Results show that a single, perfect anemometer experiencing a direct hit by the right side of the eyewall will underestimate the actual peak intensity by 10%–20%. Even an unusually large number of anemometers (e.g., 3–5) experiencing direct hits by the storm together will underestimate the peak wind speeds by 5%–10%. However, the peak winds of just one or two anemometers will provide on average a good estimate of the average peak intensity over several hours. Enhancing the variability of the simulated winds to better match observed winds does not change the results. Adding observational errors generally increases the reported peak winds, thus reducing the underestimates. If the average underestimate (negative bias) were known perfectly for each case, it could be used to correct the wind speeds, leaving only mean absolute errors of 3%–5%.
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Osuch, Andrzej, Ewa Osuch, Stanisław Podsiadłowski y Piotr Rybacki. "Analysis of Performance of the Wind-Driven Pulverizing Aerator Based on Average Wind Speeds in the Conditions of Góreckie Lake". Energies 14, n.º 10 (13 de mayo de 2021): 2796. http://dx.doi.org/10.3390/en14102796.
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In the introduction to this paper, the characteristics of Góreckie lake and the construction and operation of the wind-driven pulverizing aerator are presented. The purpose of this manuscript is to determine the efficiency of the pulverizing aerator unit in the windy conditions of Góreckie Lake. The efficiency of the pulverization aerator depends on the wind conditions at the lake. It was necessary to conduct thorough research to determine the efficiency of water flow through the pulverization segment (water pump). It was necessary to determine the rotational speed of the paddle wheel, which depended on the average wind speed. Throughout the research period, measurements of hourly average wind speed were carried out. It was possible to determine the efficiency of the machine by developing a dedicated mathematical model. The latest method was used in the research, consisting of determining the theoretical volumetric flow rates of water in the pulverizing aerator unit, based on average hourly wind speeds. Pulverization efficiency under the conditions of Góreckie Lake was determined based on 6600 average wind speeds for spring, summer and autumn, 2018. Based on the model, the theoretical efficiency of the machine was calculated, which, under the conditions of Góreckie Lake, amounted to 75,000 m3 per year.
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de Montera, Louis, Tiny Remmers, Ross O'Connell y Cian Desmond. "Validation of Sentinel-1 offshore winds and average wind power estimation around Ireland". Wind Energy Science 5, n.º 3 (17 de agosto de 2020): 1023–36. http://dx.doi.org/10.5194/wes-5-1023-2020.
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Abstract. In this paper, surface wind speed and average wind power derived from Sentinel-1 Synthetic Aperture Radar Level 2 Ocean (OCN) product were validated against four weather buoys and three coastal weather stations around Ireland. A total of 1544 match-up points was obtained over a 2-year period running from May 2017 to May 2019. The match-up comparison showed that the satellite data underestimated the wind speed compared to in situ devices, with an average bias of 0.4 m s−1, which decreased linearly as a function of average wind speed. Long-term statistics using all the available data, while assuming a Weibull law for the wind speed, were also produced and resulted in a significant reduction of the bias. Additionally, the average wind power was found to be consistent with in situ data, resulting in an error of 10 % and 5 % for weather buoys and coastal stations, respectively. These results show that the Sentinel-1 Level 2 OCN product can be used to estimate the wind resource distribution, even in coastal areas. Maps of the average and seasonal wind speed and wind power illustrated that the error was spatially dependent, which should be taken into consideration when working with Sentinel-1 Synthetic Aperture Radar data.
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Slizhе, M. O., A. B. Semergei-Chumachenko y El Hadri Youssef. "Current distribution of wind in Morocco". Ukrainian hydrometeorological journal, n.º 17 (29 de octubre de 2017): 61–69. http://dx.doi.org/10.31481/uhmj.17.2016.07.
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Information about wind is widely used in many sectors of the economy. Wind also causes many dangerous and extreme weather events. Modern climate changes require a certain revision of weather patterns previously accepted for the area. This article provides information on the current space and time distribution of wind characteristics within the territory of Morocco. During the period of 2005-2014 some monthly average wind speed values and data on repeatability of wind directions by gradations were obtained on the basis of physical and statistical analysis of results of observations of wind speed and directions performed at 26 stations.
The authors defined the character of distribution of monthly averages of wind speed within the territory and its seasonal changes. Most of the territory is covered by mountains of Morocco which encourages development of local winds. At central and northern regions of Morocco predominance of weak winds due to complex orography of terrain is observed. In the central part of Morocco there is a region with the lowest values of wind speed. Formation of the wind regime at the coastal stations takes place in a developed breeze circulation. Wind speed and direction are significantly different at the nearby stations, such as Larache and Chefchaouen, Meknes and Fez.
Increase of wind during the warmer half of a year was revealed at all stations. Nature of annual variation of average wind speed at the stations allows us to split the stations into two groups. The first group includes the stations where the average wind speed increases in summer and decreases in winter. The second group includes the stations where the average wind speed increases in spring and decreases in autumn. In the southern part and along the coast, where the terrain is flat, an increase of wind speed is observed. On open plains of the southern part of Atlantic coast during all seasons wind has a direction corresponding to direction of trade winds of the Northern hemisphere. It should be noted that the main factor forming air circulation within the territory of Morocco is represented by trade winds the intensity of which nearly doubles from summer to winter.
Formation of wind directions at the stations takes place mainly under the influence of terrain of the area. At many stations predominant wind direction in January changes by 180º in comparison to the respective July values. Therefore, characteristics of the wind regime of Morocco in 2005-2014 consist in increase of wind speed in the coastal zone and decrease thereof in mountain areas together with presence of two types of annual variation of wind speed depending on physical and geographical conditions.
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Mikhail, A. S. "Height Extrapolation of Wind Data". Journal of Solar Energy Engineering 107, n.º 1 (1 de febrero de 1985): 10–14. http://dx.doi.org/10.1115/1.3267645.
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Various models that are used for height extrapolation of short and long-term averaged wind speeds are discussed. Hourly averaged data from three tall meteorological towers (the NOAA Erie Tower in Colorado, the Battelle Goodnoe Hills Tower in Washington, and the WKY-TV Tower in Oklahoma), together with data from 17 candidate sites (selected for possible installation of large WECS), were used to analyze the variability of short-term average wind shear with atmospheric and surface parameters and the variability of the long-term Weibull distribution parameter with height. The exponents of a power-law model, fit to the wind speed profiles at the three meteorological towers, showed the same variability with anemometer level wind speed, stability, and surface roughness as the similarity law model. Of the four models representing short-term wind data extrapolation with height (1/7 power law, logarithmic law, power law, and modified power law), the modified power law gives the minimum rms for all candidate sites for short-term average wind speeds and the mean cube of the speed. The modified power-law model was also able to predict the upper-level scale factor for the WKY-TV and Goodnoe Hills Tower data with greater accuracy. All models were not successful in extrapolation of the Weibull shape factors.
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Andersen, Dale T., Christopher P. McKay y Victor Lagun. "Climate Conditions at Perennially Ice-Covered Lake Untersee, East Antarctica". Journal of Applied Meteorology and Climatology 54, n.º 7 (julio de 2015): 1393–412. http://dx.doi.org/10.1175/jamc-d-14-0251.1.
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AbstractIn November 2008 an automated meteorological station was established at Lake Untersee in East Antarctica, producing a 5-yr data record of meteorological conditions at the lake. This dataset includes five austral summer seasons composed of December, January, and February (DJF). The average solar flux at Lake Untersee for the four years with complete solar flux data is 99.2 ± 0.6 W m−2. The mean annual temperature at Lake Untersee was determined to be −10.6° ± 0.6°C. The annual degree-days above freezing for the five years were 9.7, 37.7, 22.4, 7.0, and 48.8, respectively, with summer (DJF) accounting for virtually all of this. For these five summers the average DJF temperatures were −3.5°, −1.9°, −2.2°, −2.6°, and −2.5°C. The maximum (minimum) temperatures were +5.3°, +7.6°, +5.7°, +4.4°, and +9.0°C (−13.8°, −12.8°, −12.9°, −13.5°, and −12.1°C). The average of the wind speed recorded was 5.4 m s−1, the maximum was 35.7 m s−1, and the average daily maximum was 15 m s−1. The wind speed was higher in the winter, averaging 6.4 m s−1. Summer winds averaged 4.7 m s−1. The dominant wind direction for strong winds is from the south for all seasons, with a secondary source of strong winds in the summer from the east-northeast. Relative humidity averages 37%; however, high values will occur with an average period of ~10 days, providing a strong indicator of the quasi-periodic passage of storms across the site. Low summer temperatures and high wind speeds create conditions at the surface of the lake ice resulting in sublimation rather than melting as the main mass-loss process.
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Yohana, Eflita, MSK Tony Suryo U, Binawan Luhung, Mohamad Julian Reza y M. Badruz Zaman. "Experimental Study of Wind Booster Addition for Savonius Vertical Wind Turbine of Two Blades Variations Using Low Wind Speed". E3S Web of Conferences 125 (2019): 14003. http://dx.doi.org/10.1051/e3sconf/201912514003.
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The Wind turbine is a tool used in Wind Energy Conversion System (WECS). The wind turbine produces electricity by converting wind energy into kinetic energy and spinning to produce electricity. Vertical Axis Wind Turbine (VAWT) is designed to produce electricity from winds at low speeds. Vertical wind turbines have 2 types, they are wind turbine Savonius and Darrieus. This research is to know the effect of addition wind booster to Savonius vertical wind turbine with the variation 2 blades and 3 blades. Calculation the power generated by wind turbine using energy analysis method using the concept of the first law of thermodynamics. The result obtained is the highest value of blade power in Savonius wind turbine without wind booster (16.5 ± 1.9) W at wind speed 7 m/s with a tip speed ratio of 1.00 ± 0.01. While wind turbine Savonius with wind booster has the highest power (26.3 ± 1.6) W when the wind speed of 7 m/s with a tip speed ratio of 1.26 ± 0.01. The average value of vertical wind turbine power increases Savonius after wind booster use of 56%.
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Torres Silva dos Santos, Alexandre y Cláudio Moisés Santos e Silva. "Seasonality, Interannual Variability, and Linear Tendency of Wind Speeds in the Northeast Brazil from 1986 to 2011". Scientific World Journal 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/490857.
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Wind speed analyses are currently being employed in several fields, especially in wind power generation. In this study, we used wind speed data from records of Universal Fuess anemographs at an altitude of 10 m from 47 weather stations of the National Institute of Meteorology (Instituto Nacional de Meteorologia-INMET) from January 1986 to December 2011. The objective of the study was to investigate climatological aspects and wind speed trends. To this end, the following methods were used: filling of missing data, descriptive statistical calculations, boxplots, cluster analysis, and trend analysis using the Mann-Kendall statistical method. The seasonal variability of the average wind speeds of each group presented higher values for winter and spring and lower values in the summer and fall. The groups G1, G2, and G5 showed higher annual averages in the interannual variability of wind speeds. These observed peaks were attributed to the El Niño and La Niña events, which change the behavior of global wind circulation and influence wind speeds over the region. Trend analysis showed more significant negative values for the G3, G4, and G5 groups for all seasons of the year and in the annual average for the period under study.
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Margaryan, V. G. "On the Regularities of the Spatio-Temporal Distribution of Climatic Characteristics of the Maximum Wind (Syunik Marz, Armenia)". UNIVERSITY NEWS. NORTH-CAUCASIAN REGION. NATURAL SCIENCES SERIES, n.º 3 (207) (2 de octubre de 2020): 60–68. http://dx.doi.org/10.18522/1026-2237-2020-3-60-68.
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The regularities the features of the distribution spatial basic characteristics of the maximum wind speed, as well as the temporal variability of the maximum wind speed in the territory of the Syunik marz of the Republic of Armenia. Data from the Hydrometeorology and Monitoring Center, SNCO of the Ministry of Environment of the Republic of Armenia for a period of 50 years or more (1966-2018) at 6 meteorological stations were used. It is shown that the average long-term speeds of the main characteristics of extreme wind increase in the territory with the height of the terrain, reaching maximum values in the territory with a height of more than 2000-2200 m. Deviation from these patterns is observed in Goris, due to local characteristics. To calculate and predict the maximum average annual wind speed of unexplored territories, correlation annual values of the maximum wind speed, as well as between the annual values of the maximum wind speed and the number of days with a strongwind. It was found that in general throughout the territory of the Syunik marz the annual course of the distribution of the maximum wind speed is not clearly expressed. The highest numbers of days with strong winds are observed in the cold season. For the entire study area there is a decrease in the annual maximum wind speed for the period 1966-2018.
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Butler, Bret, Steve Quarles, Christine Standohar-Alfano, Murray Morrison, Daniel Jimenez, Paul Sopko, Cyle Wold et al. "Exploring fire response to high wind speeds: fire rate of spread, energy release and flame residence time from fires burned in pine needle beds under winds up to 27 ms−1". International Journal of Wildland Fire 29, n.º 1 (2020): 81. http://dx.doi.org/10.1071/wf18216.
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The relationship between wildland fire spread rate and wind has been a topic of study for over a century, but few laboratory studies report measurements in controlled winds exceeding 5ms−1. In this study, measurements of fire rate of spread, flame residence time and energy release are reported for fires burning under controlled atmospheric conditions in shallow beds of pine needles subject to winds ranging from 0 to 27ms−1 (measured 5m above ground level). The data suggested that under constant flow conditions when winds are less than 10ms−1, fire rate of spread increases linearly at a rate of ~3% of the wind speed, which generally agrees with other laboratory-based models. When wind speed exceeds 10ms−1, the fire rate of spread response to wind remains linear but with a much stronger dependence, spreading at a rate of ~13% of the wind speed. Radiative and convective heating correlated directly to wind speed, with radiant heating increasing approximately three-fold as much as convective heating over the range of winds explored. The data suggested that residence time is inversely related to wind speed and appeared to approach a lower limit of ~20s as wind exceeded 15ms−1. Average flame residence time over the range of wind speeds was nominally 26s.
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Shrivastava, P. K. y S. P. Agrawal. "Cosmic Ray Signatures of Different Types of Solar Wind Streams". Symposium - International Astronomical Union 142 (1990): 259–60. http://dx.doi.org/10.1017/s0074180900088070.
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The earlier concept of average solar wind speed has changed with time. Besides quiet periods of low/average solar wind speeds, two different kinds of solar sources (solar flares and coronal holes) have been identified to produce high speed solar wind streams. In an earlier investigation, it was reported that the high speed streams associated to these sources produce distinctly different effects on the cosmic ray intensity (Venkatesan, et. al., 1982).
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Miller, Paul W., Alan W. Black, Castle A. Williams y John A. Knox. "Quantitative Assessment of Human Wind Speed Overestimation". Journal of Applied Meteorology and Climatology 55, n.º 4 (abril de 2016): 1009–20. http://dx.doi.org/10.1175/jamc-d-15-0259.1.
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AbstractHuman wind reports are a vital supplement to the relatively sparse network of automated weather stations in the United States, especially for localized convective winds. In this study, human wind estimates recorded in Storm Data between 1996 and 2013 were compared with instrumentally observed wind speeds from the Global Historical Climatology Network (GHCN). Nonconvective wind events in areas of flat terrain within the continental United States served as the basis for this analysis because of the relative spatial homogeneity of wind fields in these meteorological and geographic settings. The distribution of 6801 GHCN-measured gust factors (GF), defined here as the ratio of the daily maximum gust to the daily average wind, provided the reference upon which human gust reports were judged. GFs were also calculated for each human estimate by dividing the estimated gust by the GHCN average wind speed on that day. Human-reported GFs were disproportionately located in the upper tail of the observed GF distribution, suggesting that humans demonstrate a tendency to report statistically improbable wind gusts. As a general rule of thumb, humans overestimated nonconvective wind GFs by approximately one-third.
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Hinneburg, D. y G. Tetzlaff. "Calculated wind climatology of the South-Saxonian/North-Czech mountain topography including improved resolution of mountains". Annales Geophysicae 14, n.º 7 (31 de julio de 1996): 767–72. http://dx.doi.org/10.1007/s00585-996-0767-2.
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Abstract. A mesoscale model has been applied to calculate climatological means of the surface wind. A reliable average requires more than 40 model runs, which are differentiated by the direction and speed of the geostrophic wind under the assumption of neutral stratification. The frequency distributions of the geostrophic wind have been taken from observations of the 850-hPa winds at the radiosonde station in Prague for a 10-year period. The simulation results have been averaged over all sectors and speed classes of the geostrophic wind according to their frequencies. A comparison of the calculated mean wind speeds with observed ones shows deviations of about 0.4 ms–1 outside the mountains. The representation of steep topography and isolated mountains on the basis of a 3-km horizontal resolution of the simulations needs special treatment in order to reduce the gap of up to 4 ms–1 between observed and simulated mean wind speeds over mountains. Therefore, an empiric speed-up formula has been applied to the isolated mountains that otherwise would fall through the 3-km meshes. The corresponding deviations have been reduced to 1.5 ms–1.
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Ratto, Gustavo y Andrés Nico. "Preliminary wind analysis regarding different speed ranges in the city of La Plata, Argentina". Revista Brasileira de Meteorologia 27, n.º 3 (septiembre de 2012): 281–90. http://dx.doi.org/10.1590/s0102-77862012000300003.
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La Plata city (approximately 800 000 inhabitants) has intense traffic and industrial activity; nevertheless, the city has no governmental air monitoring network for air pollutants and winds have been scarcely studied. Wind observations provided here (covering 1998- 2007) belong to a weather station that was contrasted against the unique governmental site in the city area (the Airport). The present preliminary study analyses wind direction frequencies according to wind speeds and emphasizes wind patters within the first hour after calm occurrences. Results show that independently of the wind speed, wind direction frequency roses are in general similar to each other. Low wind speeds may occur most of the time (on average 58.2 %) and together with calm occurrences (on average 17.1% ) constitute an important factor for the accumulation of air pollutants. The proposed "outgoing of calm" wind direction frequency roses were found to be appropriate to gain knowledge in the structure of winds that transport pollutants towards exposed population after calm occurrences. Long term systematic meteorological fieldworks should be encouraged in the future so as to provide better tools for environmental modeling.
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Wu, Fa Ming, Lei Wang, Dian Wang y Jia Bao Jing. "Research the Influencing Factors of the Low Wind Speed Wind Turbine Fatigue Loads". Advanced Materials Research 1008-1009 (agosto de 2014): 164–68. http://dx.doi.org/10.4028/www.scientific.net/amr.1008-1009.164.
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This paper analyzes three main factors (turbulence intensity, air density, annual average wind speed ) that influence the low wind speed wind turbine fatigue loads, In order to analyze the influence of each main parameters how to affect the fatigue load of low wind speed wind turbine, using a 2000kW wind turbine as an example on the simulation test , 3 turbulence, 4 air density and 7 annual average wind speed were employed. The results show that, with the air density, turbulence intensity and the annual average wind speed increases, the wind turbine of fatigue load increase in rule approximately. Based on the above rule, it can reduce fatigue loads and prolong the life of wind turbine in design optimization of low wind speed wind turbine and sit choice.
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Atabiq, Fauzun, Budiana Budiana, Arif Febriansyah Juwito, Irfan Syahri y Ihsan Saputra. "MODIFICATION OF TWO POLES SINGLE PHASE INDUCTION MOTOR AS WIND PICO GENERATOR". JURNAL INTEGRASI 11, n.º 1 (1 de abril de 2019): 68–73. http://dx.doi.org/10.30871/ji.v11i2.1132.
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As an alternative energy, the potential of wind power in Indonesia is quite high. Some of the constraints of wind power include the presence of intermittent winds, the average wind speed in the Indonesian is relatively low, or only certain areas that have moderate to high wind speeds, so that winds that are not too tight can cause the turbines not spinning. This study is about modifying a two pole single phase induction motor as a wind pico generator. Modifications made to the squirrel cage rotor induction motor become two poles axial flux permanent magnet rotors. The test results show that a two pole pico generator is not suitable to be applied to wind power units. Electric power produced by high-speed prime mover, above 1000 rpm only 2.53 Watts. Whereas when it is operated at low speed, less than 200 rpm, the maximum output power power only 44 mW.
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Miller, Craig, John Holmes, David Henderson, John Ginger y Murray Morrison. "The Response of the Dines Anemometer to Gusts and Comparisons with Cup Anemometers". Journal of Atmospheric and Oceanic Technology 30, n.º 7 (1 de julio de 2013): 1320–36. http://dx.doi.org/10.1175/jtech-d-12-00109.1.
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Abstract The Dines pressure tube anemometer was the primary wind speed recording instrument used in Australia until it was replaced by Synchrotac cup anemometers in the 1990s. Simultaneous observations of the gust wind speeds recorded using both types of anemometers during tropical cyclones have, however, raised questions about the equivalency of the gust wind speeds recorded using the two instruments. An experimental study of the response of both versions of the Dines anemometer used in Australia shows that the response of the anemometer is dominated by the motion of the float manometer used to record the wind speed. The amplitude response function shows the presence of two resonant peaks, with the amplitude and frequency of the peaks depending on the instrument version and the mean wind speed. Comparison of the gust wind speeds recorded using Dines and Synchrotac anemometers using random process and linear system theory shows that, on average, the low-speed Dines anemometer records values 2%–5% higher than those recorded using a Synchrotac anemometer under the same conditions, while the high-speed Dines anemometer records values 3%–7% higher, depending on the mean wind speed and turbulence intensity. These differences are exacerbated with the adoption of the WMO-recommended 3-s moving average gust wind speed when reporting the Synchrotac anemometer gust wind speeds, rising to 6%–12% and 11%–19% for low- and high-speed Dines anemometers, respectively. These results are consistent with both field observations and an independent extreme value analysis of simultaneously observed gust wind speeds at seven sites in northern Australia.
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Eide, Siri Sofie, John Bjørnar Bremnes y Ingelin Steinsland. "Bayesian Model Averaging for Wind Speed Ensemble Forecasts Using Wind Speed and Direction". Weather and Forecasting 32, n.º 6 (1 de diciembre de 2017): 2217–27. http://dx.doi.org/10.1175/waf-d-17-0091.1.
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Abstract In this paper, probabilistic wind speed forecasts are constructed based on ensemble numerical weather prediction (NWP) forecasts for both wind speed and wind direction. Including other NWP variables in addition to the one subject to forecasting is common for statistical calibration of deterministic forecasts. However, this practice is rarely seen for ensemble forecasts, probably because of a lack of methods. A Bayesian modeling approach (BMA) is adopted, and a flexible model class based on splines is introduced for the mean model. The spline model allows both wind speed and wind direction to be included nonlinearly. The proposed methodology is tested for forecasting hourly maximum 10-min wind speeds based on ensemble forecasts from the European Centre for Medium-Range Weather Forecasts at 204 locations in Norway for lead times from +12 to +108 h. An improvement in the continuous ranked probability score is seen for approximately 85% of the locations using the proposed method compared to standard BMA based on only wind speed forecasts. For moderate-to-strong wind the improvement is substantial, while for low wind speeds there is generally less or no improvement. On average, the improvement is 5%. The proposed methodology can be extended to include more NWP variables in the calibration and can also be applied to other variables.
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Ignatiev, S. G. y S. V. Kiseleva. "SHAPING OF AN AUTONOMOUS POWER SYSTEM FOR GUARANTEED POWER SUPPLY WITH THE PREDOMINANCE WIND ENERGY". Alternative Energy and Ecology (ISJAEE), n.º 22-24 (5 de noviembre de 2018): 28–50. http://dx.doi.org/10.15518/isjaee.2018.22-24.028-050.
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Optimization of the autonomous wind-diesel plants composition and of their power for guaranteed energy supply, despite the long history of research, the diversity of approaches and methods, is an urgent problem. In this paper, a detailed analysis of the wind energy characteristics is proposed to shape an autonomous power system for a guaranteed power supply with predominance wind energy. The analysis was carried out on the basis of wind speed measurements in the south of the European part of Russia during 8 months at different heights with a discreteness of 10 minutes. As a result, we have obtained a sequence of average daily wind speeds and the sequences constructed by arbitrary variations in the distribution of average daily wind speeds in this interval. These sequences have been used to calculate energy balances in systems (wind turbines + diesel generator + consumer with constant and limited daily energy demand) and (wind turbines + diesel generator + consumer with constant and limited daily energy demand + energy storage). In order to maximize the use of wind energy, the wind turbine integrally for the period in question is assumed to produce the required amount of energy. For the generality of consideration, we have introduced the relative values of the required energy, relative energy produced by the wind turbine and the diesel generator and relative storage capacity by normalizing them to the swept area of the wind wheel. The paper shows the effect of the average wind speed over the period on the energy characteristics of the system (wind turbine + diesel generator + consumer). It was found that the wind turbine energy produced, wind turbine energy used by the consumer, fuel consumption, and fuel economy depend (close to cubic dependence) upon the specified average wind speed. It was found that, for the same system with a limited amount of required energy and high average wind speed over the period, the wind turbines with lower generator power and smaller wind wheel radius use wind energy more efficiently than the wind turbines with higher generator power and larger wind wheel radius at less average wind speed. For the system (wind turbine + diesel generator + energy storage + consumer) with increasing average speed for a given amount of energy required, which in general is covered by the energy production of wind turbines for the period, the maximum size capacity of the storage device decreases. With decreasing the energy storage capacity, the influence of the random nature of the change in wind speed decreases, and at some values of the relative capacity, it can be neglected.
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Jhon, Wabang A., Abanat D. J. Jufra y Hattu Edwin. "ANALISA PERFORMA TURBIN ANGIN SUMBU HORISONTAL BERSUDU AIRFOIL MELALUI VARIASI JUMLAH SUDU". ROTOR 11, n.º 2 (1 de noviembre de 2018): 18. http://dx.doi.org/10.19184/rotor.v11i2.9338.
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Indonesia is an area that has the potential for sufficient wind resources to be utilized for kinetic energy into other energy such as mechanical energy and electrical energy through its generators (generators). The way to utilize wind kinetic energy into other energy is through a device called a wind turbine. Wind turbines have been around since ancient times, and are called airfoil angled wind turbines. This airfoil wind turbine is designed only for areas with average wind speeds above 6m / s. While in Indonesia not all regions have the same wind speed. In certain seasons, the average wind speed is below 6 m / s. This has become a major problem in regions that have average wind speeds below 6 m / s. Seeing this condition, there is a need for scientific research to obtain wind turbines that can be used in areas with average wind speeds below 5m / s. For this reason, the research I want to do is get a wind turbine that can be used as a power plant in areas that have wind speeds below 6m / s. This research was conducted on the basis of scientific theory in fluid mechanics regarding the sweeping area of wind turbines and the performance of variations in the number of blades in the wind. In addition, the research in several scientific journals was used as the basis of this research
This research method is an experimental method, in the form of testing a wind turbine axis prototype horizontal and airfoil axis. The details of the research activity are the design and manufacture of laboratory scale horizontal airfoil axis turbines. Next, testing with a fan as a source of wind. The fan used has three variations of speed, all of which are used to determine the lowest average wind speed that can be applied. The results of the research are where wind turbines with the greatest torque and power and the Coefficient of Performance (CP) with the highest value will be used as a result to be applied to the community. Based on experimental data, it can be concluded that the greatest torque and power occur in turbines with 4 blades with details at speed 1, the largest torque and power are 0.201 Nm and 4.5 W; at speed 2, the biggest torque and power are 0.25 Nm and 7.21 W; at speed 3, the biggest torque and power are 0.28 Nm and 8.35 W
Keywords: wind turbine, airfoil, nozzle, diffuser
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Standridge, Charles R., Daivd Zeitler, Aaron Clark, Tyson Spoolma, Erik Nordman, T. Arnold Boezaart, Jim Edmonson et al. "Lake Michigan Wind Assessment Analysis, 2012 and 2013". International Journal of Renewable Energy Development 6, n.º 1 (22 de marzo de 2017): 19–27. http://dx.doi.org/10.14710/ijred.6.1.19-27.
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A study was conducted to address the wind energy potential over Lake Michigan to support a commercial wind farm. Lake Michigan is an inland sea in the upper mid-western United States. A laser wind sensor mounted on a floating platform was located at the mid-lake plateau in 2012 and about 10.5 kilometers from the eastern shoreline near Muskegon Michigan in 2013. Range gate heights for the laser wind sensor were centered at 75, 90, 105, 125, 150, and 175 meters. Wind speed and direction were measured once each second and aggregated into 10 minute averages. The two sample t-test and the paired-t method were used to perform the analysis. Average wind speed stopped increasing between 105 m and 150 m depending on location. Thus, the collected data is inconsistent with the idea that average wind speed increases with height. This result implies that measuring wind speed at wind turbine hub height is essential as opposed to using the wind energy power law to project the wind speed from lower heights. Average speed at the mid-lake plateau is no more that 10% greater than at the location near Muskegon. Thus, it may be possible to harvest much of the available wind energy at a lower height and closer to the shoreline than previously thought. At both locations, the predominate wind direction is from the south-southwest. The ability of the laser wind sensor to measure wind speed appears to be affected by a lack of particulate matter at greater heights.Article History: Received June 15th 2016; Received in revised form January 16th 2017; Accepted February 2nd 2017 Available onlineHow to Cite This Article: Standridge, C., Zeitler, D., Clark, A., Spoelma, T., Nordman, E., Boezaart, T.A., Edmonson, J., Howe, G., Meadows, G., Cotel, A. and Marsik, F. (2017) Lake Michigan Wind Assessment Analysis, 2012 and 2013. Int. Journal of Renewable Energy Development, 6(1), 19-27.http://dx.doi.org/10.14710/ijred.6.1.19-27
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Ata, Raşit y Numan Çetin. "Analysis of Height Affect on Average Wind Speed by ANN". Mathematical and Computational Applications 16, n.º 3 (1 de diciembre de 2011): 556–64. http://dx.doi.org/10.3390/mca16030556.
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Rakhmanov, R. S., D. A. Gadzhiibragimov, G. G. Bakhmydov, M. Kh Alikberov y A. V. Tarasov. "ON THE EVALUATION OF WORKING CONDITIONS IN OPEN AREA IN THE WINTER SEASON". Hygiene and sanitation 98, n.º 4 (28 de octubre de 2019): 424–27. http://dx.doi.org/10.18821/0016-9900-2019-98-4-424-427.
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Introduction. The evaluation of the impact influence of weather and climatic conditions on humans in cold (winter) period was done since there was not the method of evaluation of working conditions according to the degree of harmfulness and danger. Also, the sanitary norms and rules 2.2.4.3359-16 does not contain the method of risk evaluation of the influence of factors upon the human organism. Мaterial and Methods. The authors evaluated the influence of various combinations of ambient temperature and wind speed upon under conditions of IV climatic region in I zone (the Republic of Dagestan - at an altitude of 4 m., 1040 m. and 1661 m above sea level and the Kaliningrad region) according to wind cooling. It was found a possible discomfort sensation at an average speed of winds and temperatures (wind cooling index (WCI) more 763,7 Kcal/m2) as well as overcooling risk in combinations of average temperature and maximum wind speed, an average speed of the wind and the minimum temperature. Maximum wind speeds in combination with minimal temperatures exceeded WCI threshold by 1,25-2,1 times. It should be noted that the studies were conducted under conditions of an increased humidity which had a negative influence upon the human organism, but in combination with the high wind speed and low temperatures, the effect might be more considerable. results. In accordance with the method, in attachment 17 in manual Р 2.2.2006-05, working conditions were classified as harmful. By calculation on indices of the minimal temperature and maximum wind speed, indices of equivalent temperatures reached up to considerable values. Probably, the use of the method does not prove its value. conclusion. The fixing of complex influence (in the cold period) of air velocity, ambient temperature, air humidity and detecting of health risk due to weather and climatic conditions remain a topical theoretical and practical problem.
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Montoya, R. D. y A. F. Osorio. "Methodology to Correct Wind Speed during Average Wind Conditions: Application to the Caribbean Sea". Journal of Atmospheric and Oceanic Technology 31, n.º 9 (1 de septiembre de 2014): 1922–45. http://dx.doi.org/10.1175/jtech-d-13-00124.1.
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Abstract The spatial and temporal variability of ocean wind waves plays an important role in many engineering and environmental problems. Although research in this area has been improved in recent decades thanks to the emergence of satellite data, in many cases this information does not have the appropriate resolution for more detailed and local research. In view of this, reanalysis data developed by several meteorological agencies have appeared as a good alternative to force the most popular ocean wind-wave models. Thus, to achieve more accuracy in the data, the 60-yr Global Atmospheric Reanalysis 1 carried out by the National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) has been corrected, employing the vector correlation and triple collocation theories combined with information from different accurate sources. The comparison of wind speed with satellite and in situ buoy data before correction reveals an important underestimation for areas near the Colombian coast. The wind speed root-mean-square error (RMSE) between corrected data and satellite measurements at locations near the Colombian Caribbean coast without calibration is 3.8 m s−1, while for corrected data it is 2.0 m s−1, showing a decrease in the RMSE of almost 47%. For significant wave height for buoy 41194 (Barranquilla, Colombia), the RMSE between the modeled data and measurements without correction is 0.99 m, while for the corrected data it is 0.40 m, showing a decrease in the RMSE of almost 55%. The results obtained clearly show an increase in the accuracy of the calibrated wind speed.
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McCandless, Tyler C. y Sue Ellen Haupt. "The super-turbine wind power conversion paradox: using machine learning to reduce errors caused by Jensen's inequality". Wind Energy Science 4, n.º 2 (4 de junio de 2019): 343–53. http://dx.doi.org/10.5194/wes-4-343-2019.
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Abstract. Wind power is a variable generation resource and therefore requires accurate forecasts to enable integration into the electric grid. Generally, the wind speed is forecast for a wind plant and the forecasted wind speed is converted to power to provide an estimate of the expected generating capacity of the plant. The average wind speed forecast for the plant is a function of the underlying meteorological phenomena being predicted; however, the wind speed for each turbine at the farm is also a function of the local terrain and the array orientation. Conversion algorithms that assume an average wind speed for the plant, i.e., the super-turbine power conversion, assume that the effects of the local terrain and array orientation are insignificant in producing variability in the wind speeds across the turbines at the farm. Here, we quantify the differences in converting wind speed to power at the turbine level compared with a super-turbine power conversion for a hypothetical wind farm of 100 2 MW turbines as well as from empirical data. The simulations with simulated turbines show a maximum difference of approximately 3 % at 11 m s−1 with a 1 m s−1 standard deviation of wind speeds and 8 % at 11 m s−1 with a 2 m s−1 standard deviation of wind speeds as a consequence of Jensen's inequality. The empirical analysis shows similar results with mean differences between converted wind speed to power and measured power of approximately 68 kW per 2 MW turbine. However, using a random forest machine learning method to convert to power reduces the error in the wind speed to power conversion when given the predictors that quantify the differences due to Jensen's inequality. These significant differences can lead to wind power forecasters overestimating the wind generation when utilizing a super-turbine power conversion for high wind speeds, and indicate that power conversion is more accurately done at the turbine level if no other compensatory mechanism is used to account for Jensen's inequality.
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Grah, Vanessa de F., Isaac de M. Ponciano y Tarlei A. Botrel. "Potential for wind energy generation in Piracicaba, SP, Brazil". Revista Brasileira de Engenharia Agrícola e Ambiental 18, n.º 5 (mayo de 2014): 559–64. http://dx.doi.org/10.1590/s1415-43662014000500014.
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Wind power has gained space in Brazil's energy matrix, being a clean source and inexhaustible. Therefore, it becomes important to characterize the wind potential of a given location, for future applications. The main objective of the present study was to estimate the wind energy potential in Piracicaba, SP, Brazil. The wind speed data were collected by an anemometer installed at the Meteorological Station Luiz de Queiroz College of Agriculture, Piracicaba-SP. The wind speed variability was represented by the Weibull frequency distribution, a probability density function of two parameters (k and c). The parameters k and c were used to correlate the Gamma function with the annual average wind speed, the variance and power mean density. A wind profile was made to evaluate the behavior of historical average speeds at higher altitudes measured by anemometer, to estimate the gain in power density. The values of k for all heights were close to 1 which corresponds to a wind regime highly variable, and c values were also low representing a low average speed of the location. The location was characterized as being unfavorable for the application of wind turbines for power generation.
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Knoop, Steven, Pooja Ramakrishnan y Ine Wijnant. "Dutch Offshore Wind Atlas Validation against Cabauw Meteomast Wind Measurements". Energies 13, n.º 24 (11 de diciembre de 2020): 6558. http://dx.doi.org/10.3390/en13246558.
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The Dutch Offshore Wind Atlas (DOWA) is validated against wind speed and direction measurements from the Cabauw meteorological mast for a 10-year period and at heights between 10 m and 200 m. The validation results are compared to the Royal Netherlands Meteorological Institute (KNMI) North Sea Wind (KNW) atlas. It is found that the average difference (bias) between DOWA wind speeds and those measured at Cabauw varies for the different heights between −0.1 m/s to 0.3 m/s. Significant differences between DOWA and KNW are only found at altitudes of 10 m and 20 m, where KNW performs better. For heights above 20 m, there is no significant difference between DOWA and KNW with respect to the 10-year averaged wind speed bias. The diurnal cycle is better captured by DOWA compared to KNW, and the hourly correlation is slightly improved. In addition, a comparison with the global European Center for Medium-Range Weather Forecasts (ECMWF) ERA-Interim and ERA5 reanalyses (used for KNW and DOWA, respectively) is made, highlighting the added skill provided by downscaling those global datasets with the weather model HARMONIE.
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Dierer, Silke, Tim de Paus, Francesco Durante, Erik Gregow, Bernhard Lange, Alfredo Lavagnini, Martin Strack y Bengt Tammelin. "Predicting Wind Speed for Wind Energy; Progress of the WINDENG Project". Wind Engineering 29, n.º 5 (septiembre de 2005): 393–408. http://dx.doi.org/10.1260/030952405775992616.
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The suitability of the computer model MM5 for predicting wind speed, and hence wind energy, is investigated by performing simulations for different geographical regions. The focus is on wind speed in the lowest 200 m of the planetary boundary layer (PBL). The dependency of the simulated wind speed on PBL parameterization and atmospheric stability is studied. The smallest deviation between measured and simulated wind speed, averaged over a three-day period, is 1% and occurs for an off-shore simulation with unstable stratification. The largest deviations of 31% and 20% occur with orographically structured terrain, stable stratification and weak synoptic forcing. The results suggest that unstable conditions are simulated with better accuracy by MM5. Changes of the PBL scheme cause wind speed variations between 9% and 40% of the average wind speed. None of the PBL schemes is clearly the best and their performance can strongly vary for different conditions. Nevertheless, the Mellor-Yamada-Janjic (ETA) and the Blackadar PBL parameterization (BLK) schemes seem to be the most suitable schemes for wind energy applications. Additionally, MM5 was successfully adapted for idealised, stationary simulations in order to calculate a wind-climatology for Sardinia using a statistical-dynamical downscaling approach.
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Wang, Yu, Changan Zhu, Xiaodong Ye, Jianghai Zhao y Deji Wang. "Wind Speed Prediction based on Spatio-Temporal Covariance Model Using Autoregressive Integrated Moving Average Regression Smoothing". International Journal of Pattern Recognition and Artificial Intelligence 35, n.º 08 (1 de abril de 2021): 2159031. http://dx.doi.org/10.1142/s021800142159031x.
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It is essential to enhance the ability of wind speeds forecasting for wind energy and wind resource planning. For this purpose, a hybrid strategy has been proposed based on spatio-temporal covariance model which combined the spatio-temporal ordinary kriging (STOK) technology with autoregressive integrated moving average (ARIMA) regression smoothing method. This is because wind speed time series exhibits a long-term dependency. In the case study, both STOK method and ARIMA method are employed and their performances are compared. The ARIMA model can obtain a necessary and sufficient smoothing condition for them to be smoothed. Meanwhile, further theoretical analysis is provided to discuss why the STOK method is potentially more accurate than the ARIMA method for wind speed time series prediction. Results show that the proposed method outperforms the Non-Sep-Gneiting model by 9% and 7.2% in terms of mean absolute error (MAE) and root-mean-square error (RMSE).
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Lin, Yujie, Yumeng Jin y Hong Jin. "Field Study on the Microclimate of Public Spaces in Traditional Residential Areas in a Severe Cold Region of China". International Journal of Environmental Research and Public Health 16, n.º 16 (20 de agosto de 2019): 2986. http://dx.doi.org/10.3390/ijerph16162986.
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As residential environment science advances, the environmental quality of outdoor microclimates has aroused increasing attention of scholars majoring in urban climate and built environments. Taking the microclimate of a traditional residential area in a severe cold city as the study object, this study explored the influence of spatial geometry factors on the microclimate of streets and courtyards by field measurements, then compared the differences in microclimate of distinct public spaces. The results are as follows. (1) The temperature of a NE-SW (Northeast-Southwest) oriented street was higher than that of a NW-SE (Northwest-Southeast) oriented street in both summer and winter, with an average temperature difference of 0.7–1.4 °C. The wind speeds in the latter street were slower, and the difference in average wind speed was 0.2 m/s. (2) In the street with a higher green coverage ratio, the temperature was much lower, a difference that was more obvious in summer. The difference in mean temperature was up to 1.2 °C. The difference in wind speed between the two streets was not obvious in winter, whereas the wind speed in summer was significantly lower for the street with a higher green coverage ratio, and the difference in average wind speed was 0.7 m/s. (3) The courtyards with higher SVF (sky view factor) had higher wind speeds in winter and summer, and the courtyards with larger SVF values had higher temperatures in summer, with an average temperature difference of 0.4 °C. (4) When the spaces had the same SVF values and green coverage ratios, the temperature of the street and courtyard were very similar, in both winter and summer. The wind speed of the street was significantly higher than the courtyard in summer, and the wind speed difference was 0.4 m/s.
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Fadhli, Fadhli y Ichsan Syahputra. "Identifikasi Potensi Pembangkit Listrik Tenaga Hybrid (PLTH) Angin dan Surya di Kabupaten Aceh Besar". Jurnal Teknik Sipil Unaya 5, n.º 2 (9 de agosto de 2019): 39–47. http://dx.doi.org/10.30601/jtsu.v5i2.287.
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The Wind and Solar Hybrid Power Plant (PLTH) research is expected to be able to contribute to assist the development of electricity supply in Aceh and gradually reduce and substitute the use of fossil energy. Hybrid Power Plant (PLTH) by combining wind energy and solar energy is a sustainable electricity supply technology that is increasingly popular because it is environmentally friendly and is not much constrained by land conversion. This research by measuring wind speed and solar radiation was carried out at selected locations in Aceh Besar District namely Lhoksedu, Lampuuk, Lambadeuk and Krueng Raya. The Lhokseudu location has a maximum wind speed of 6.3 m / sec and an average wind speed of 1 m / sec while solar radiation is a maximum of 764.90 W / m2, an average of 467.87 W / m2 and a minimum of 155.40 W / m2. Location Lampuuk maximum wind speed of 7.6 m / sec and average wind speed of 1.1 m / sec while maximum solar radiation is 1193 W / m2, average 678.74 W / m2 and minimum 30.20 W / m2. The Lambadeuk location has a maximum wind speed of 13 m / sec and an average wind speed of 1.3 m / sec while maximum solar radiation is 1589 W / m2, an average of 626.01 W / m2 and a minimum of 38.50 W / m2. The location of Krueng Raya is a maximum wind speed of 9.4 m / sec and an average wind speed of 3.1 m / sec while solar radiation is a maximum of 1019 W / m2, an average of 811.65 W / m2 and a minimum of 493.50 W / m2. Based on the results of data collection and analysis of wind speed and solar radiation that have been carried out including using secondary data / wind speed data from Blang Bintang BMKG Station at Sultan Iskandar Muda Airport and BMKG Indrapuri Station, it can be concluded that the more potential for PLTH development is the location Lambadeuk and Krueng Raya.
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Clive, P. J. M. "Compensation of Bias in Lidar Wind Resource Assessment". Wind Engineering 32, n.º 5 (octubre de 2008): 415–32. http://dx.doi.org/10.1260/030952408786411949.
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A number of vector and volume averaging considerations arise in relation to remote sensing, and in particular, Lidar. 1) Remote sensing devices obtain vector averages. The magnitude of a vector average is less than or equal to the scalar average obtained over the same period. The use of Lidars in wind power applications has introduced practices entailing the estimation of scalar average point quantities by the measurement of vector averages over volumes and vice versa. The relationship between vector and scalar averages, and the relationship between volume and point measurements, must therefore both be understood. It is found that their ratio depends upon wind direction variability according to a Bessel function of the standard deviation of the wind direction during the averaging interval. The impact of wind direction variability on power production is also explored. 2) The finite probe length of remote sensing devices incurs a volume averaging bias if wind shear is non-linear. The sensitivity of the devices to signals from a range of heights produces volume averages representing wind speeds within that range. If the wind shear is described by a logarithmic wind profile the apparent height, at which the average wind speed occurs, is found to depend on simple geometrical arguments concerning configuration height and probe length independent of the degree of wind shear. Similar arguments are applied to determine the ideal height across the rotor at which to acquire wind speed data for power curves. 3) The common restriction of the locus of points at which radial velocity measurements are made to the circumference of a horizontally oriented disc at a particular height is seen to introduce ambiguity into results when dealing with wind vector fields which are not uniform.
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Rahdari, Mohammad Reza y Andrés Rodríguez-Seijo. "Monitoring Sand Drift Potential and Sand Dune Mobility over the Last Three Decades (Khartouran Erg, Sabzevar, NE Iran)". Sustainability 13, n.º 16 (12 de agosto de 2021): 9050. http://dx.doi.org/10.3390/su13169050.
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Aeolian sediments cover about 6% of the earth’s surface, of which 97% occur in arid regions, and these sediments cover about 20% of the world’s lands. Sand drifts can harm sensitive ecosystems; therefore, this research has aimed to study wind regimes and the monitoring of sand drift potential and dune mobility in the Khartouran Erg (NE Iran). The study investigated 30 years of wind speed and direction to better understand sand dune mobility processes using the Fryberger and Tsoar methods. The results of the wind regime study showed that the eastern (33.4%) and northeastern (14.3%) directions were more frequent, but the study of winds greater than the threshold (6 m/s) in winter, spring, and autumn indicated the dominance of eastern and northern wind directions. Findings of calm winds showed that winters (40.4%) had the highest frequency, and summers (15%) had the lowest frequency; the annual frequency was 30%. The average wind speed in summers was the highest (4.38 m/s), and, in the winters, it was the lowest (2.28 m/s); the annual average wind speed was 3.3 m/s. The annual drift potential (DP = 173 VU) showed that it was categorized as low class, and the winds carried sand to the southwest. The monitoring of drift potential showed that there was a sharp increase between 2003 and 2008, which could have been attributed to a change in wind speeds in the region. Unite directional index, the index of directional variability, has been alternating from 0.3 to 0.6 for 30 years. Furthermore, monitoring of sand mobility recorded a value from 0.1 to 0.4, and the lowest and highest values were registered from 0.08 to 0.9, with an average of 0.27. Finally, it can be concluded that sand dunes have been fixed for a long time, and the intensity of the mobility index is affected by climate changes.
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Belu, Radian y Darko Koracin. "Statistical and Spectral Analysis of Wind Characteristics Relevant to Wind Energy Assessment Using Tower Measurements in Complex Terrain". Journal of Wind Energy 2013 (10 de julio de 2013): 1–12. http://dx.doi.org/10.1155/2013/739162.
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The main objective of the study was to investigate spatial and temporal characteristics of the wind speed and direction in complex terrain that are relevant to wind energy assessment and development, as well as to wind energy system operation, management, and grid integration. Wind data from five tall meteorological towers located in Western Nevada, USA, operated from August 2003 to March 2008, used in the analysis. The multiannual average wind speeds did not show significant increased trend with increasing elevation, while the turbulence intensity slowly decreased with an increase were the average wind speed. The wind speed and direction were modeled using the Weibull and the von Mises distribution functions. The correlations show a strong coherence between the wind speed and direction with slowly decreasing amplitude of the multiday periodicity with increasing lag periods. The spectral analysis shows significant annual periodicity with similar characteristics at all locations. The relatively high correlations between the towers and small range of the computed turbulence intensity indicate that wind variability is dominated by the regional synoptic processes. Knowledge and information about daily, seasonal, and annual wind periodicities are very important for wind energy resource assessment, wind power plant operation, management, and grid integration.
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Sopian, Kamaruzzaman y Tamer Khatib. "Wind Energy Potential in Nine Coastal Sites in Malaysia". مجلة جامعة فلسطين التقنية خضوري للأبحاث 1, n.º 1 (20 de agosto de 2013): 10–15. http://dx.doi.org/10.53671/ptukrj.v1i1.7.
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In this paper, the wind energy potential in Malaysia is examined by analyzing hourly wind speed data for nine coastal sites namely Bintulu, Kota Kinabalu, Kuala Terengganu, Kuching, Kudat, Mersing, Sandakan, Tawau and Pulau Langkawi. The monthly averages of wind speed and wind energy are calculated. Moreover, the wind speed distribution histogram is constructed for these sites. The results showed that the average wind speed for these sites is in the range of (1.8-2.9) m/s while the annual energy of the wind hitting a wind turbine with a 1 m2 swept area is in the range of (15.4-25.2) kWh/m2.annum. This paper provides a data bank for wind energy for Malaysia.
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Sopian, Kamaruzzaman y Tamer Khatib. "Wind Energy Potential in Nine Coastal Sites in Malaysia". مجلة جامعة فلسطين التقنية للأبحاث 1, n.º 1 (20 de agosto de 2013): 10–15. http://dx.doi.org/10.53671/pturj.v1i1.7.
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In this paper, the wind energy potential in Malaysia is examined by analyzing hourly wind speed data for nine coastal sites namely Bintulu, Kota Kinabalu, Kuala Terengganu, Kuching, Kudat, Mersing, Sandakan, Tawau and Pulau Langkawi. The monthly averages of wind speed and wind energy are calculated. Moreover, the wind speed distribution histogram is constructed for these sites. The results showed that the average wind speed for these sites is in the range of (1.8-2.9) m/s while the annual energy of the wind hitting a wind turbine with a 1 m2 swept area is in the range of (15.4-25.2) kWh/m2.annum. This paper provides a data bank for wind energy for Malaysia.
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Tar, Károly. "Some statistical characteristics of monthly average wind speed at various heights". Renewable and Sustainable Energy Reviews 12, n.º 6 (agosto de 2008): 1712–24. http://dx.doi.org/10.1016/j.rser.2007.01.014.
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Nfaoui, H., J. Buret y A. A. M. Sayigh. "Stochastic simulation of hourly average wind speed sequences in Tangiers (Morocco)". Solar Energy 56, n.º 3 (marzo de 1996): 301–14. http://dx.doi.org/10.1016/0038-092x(95)00103-x.
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Gul, Mehr, Nengling Tai, Wentao Huang, Muhammad Nadeem y Moduo Yu. "Assessment of Wind Power Potential and Economic Analysis at Hyderabad in Pakistan: Powering to Local Communities Using Wind Power". Sustainability 11, n.º 5 (6 de marzo de 2019): 1391. http://dx.doi.org/10.3390/su11051391.
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Wind power is the fastest growing and environmentally sustainable source of energy among all available renewable energy resources. The primary objective of this paper is to analyze the wind characteristics and power potential at Hyderabad, Southeastern province in Pakistan. Two years of wind speed data measured at 10 m above ground level (AGL) have been considered in this study. The annually, monthly, and seasonal variations in wind speed were analyzed, and minimum, maximum, and average values of recorded wind speeds are presented in this paper. Weibull and Rayleigh distribution functions have been applied to analyze the wind characteristics and evaluate the wind power potential of the proposed site. The Weibull shape k and scale c parameters have been estimated using the Weibull function. The higher values of k showed that the wind speed is steady at the site. The average wind speed was found above 6 m/s throughout the year. The most probable wind speed (Vmp) and maximum carrying energy (VmaxE) wind speed were also calculated using Weibull parameters. Root mean square error (RMSE), the coefficient of determination (R2), and mean bias error (MBE) were computed to ensure the good fit of Weibull distribution function. The annual average wind power and energy densities were estimated at more than 255 W/m2 and 2245 kWh/m2, respectively. The power density calculated by Weibull and Rayleigh functions was compared with that calculated by using measured wind data. The energy output and capacity factor of different commercially available wind turbines (WTs), i.e., power ratings from 0.33 to 2.75 MW, have been calculated. The cost of energy was estimated and ranged from $19.27 to $32.80 per MWh. Wind power potential and economic analysis of the collected data reveals that the site is suitable for developing wind power generation projects to power the local communities.
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Farrugia, R. N. y T. Sant. "Wind Speed Measurements in the Vicinity of a Tubular Mast: Influence of Data Selection Methods on Wind Speed Average Determination". Wind Engineering 38, n.º 2 (abril de 2014): 147–66. http://dx.doi.org/10.1260/0309-524x.38.2.147.
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Rajab, Zakariya, Yousef sassi, Ahmed Taher, Asharf Khalil y Faisal Mohamed. "A practical seasonal performance evaluation of small wind turbine in urban environment". Wind Engineering 43, n.º 4 (23 de julio de 2019): 344–58. http://dx.doi.org/10.1177/0309524x19858255.
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Due to the low environmental impact, smaller storage units, low wind speed, low power system distribution network impact, and low maintenance, small wind turbines have gained more attention. However, the usage of small turbines usually faces several shortcomings, and the actual yield is often lower than expected, generally because the output power is low when compared with the manufacturer, and the actual wind turbine behavior does not reproduces. In a view of performance evaluation of a small wind turbines using high-accuracy measurement devices to measure wind speed and energy production, this article illustrates an experimental seasonal performance evaluation of a 0.5-kW Hummer small wind turbine, placed in an urban environment. In addition, we study the influence of the height in the energy output and analyze its effect in the system performance, which is another aim in this work. Three cases have been carried out: 4 m in order to protect rotor blades during strong winds and storms in the first scenario and 6 m the manufacturing height in the second scenario while 10 m the third case. A 0.5-kW Hummer wind turbine has been installed in Noagia-Benghazi since 2010 for educational purposes, field studies, training, graduate projects, and research. The wind turbine seasonal performance under different periods was obtained and compared in terms of the wind speed, output power, energy production, and average wind speed. The average wind speed is 6.4, 4, 5.8, and 4 m/s, and the average energy production is 948.24, 172.8, 648, and 172.8 kWh in spring, summer, winter, and autumn, respectively. Spring has the highest wind speed followed by winter and autumn then summer for all height. Improvement is attained if the wind turbine tower height is 6 m, and 10 m where more energy is harvested. But the main problem at 10 m is that the system control needs more improvement because the wind speed exceeds 14 m/s which represents the maximum speed. The system can produce about 1.942 MW yearly and save CO2 emissions.
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Wei, Lian-Jiang, Meng-Wei Wang, Sheng Li y Zong-Kang Wei. "Line wind speed distribution model of rectangular tunnel cross-section". Thermal Science 23, n.º 3 Part A (2019): 1513–19. http://dx.doi.org/10.2298/tsci180707218w.
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Accurate monitoring of the tunnel wind speed plays a key role in achieving intelligent mine ventilation. Based on the difficulty faced in precise reflection of the average tunnel wind speed by point wind speed monitoring, this paper puts forward a method for accurate monitoring the tunnel wind speed by large-span ultrasonic linear wind speed sensor based on the method of the time difference. Besides, as to the core problem of representing the average section wind speed by section-linear wind speed, the distribution rules of section wind speed in rectangular tunnel with various support forms is studied through combing theoretical analysis and experimental verification. The results could be well applied to rapid determination of ventilation parameters in other coal mines, which is better for the ventilation management of mines.
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Savadjiev, Konstantin y Masoud Farzaneh. "Probabilistic model of combined wind and ice loads on overhead power line conductors". Canadian Journal of Civil Engineering 30, n.º 4 (1 de agosto de 2003): 704–10. http://dx.doi.org/10.1139/l03-026.
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There is evidence that extreme ice loads combined with moderately high winds may cause catastrophic damage to overhead power lines and prolonged periods of electrical power outage. In this paper, a probabilistic model for combined wind and ice loads was developed for establishing realistic and conservative criteria for design and normalization. The proposed model combines icing of extreme thickness with a moderate wind speed, Vice, reduced by a reduction factor, kr, with respect to the extreme wind speed, Vmax. The evaluation of kr, which is the main purpose of this paper, is done by means of statistical analysis of samples taken from the same initial distribution of hourly wind speeds, Vh. The size of samples corresponds to the average annual icing persistency period, Tipp, observed in the climatic conditions of Quebec. This period, which was established in an earlier study by the authors using statistical analysis of data from the Hydro-Québec passive ice meter (PIM) network, is evaluated to be on average 144 h/year. It was found that kr ranges from 0.4 to 0.7, mainly as a function of the coefficient of variation (COV) of the initial distribution of wind speeds and the return period prescribed for extreme climatic loads.Key words: combined wind and ice loads, probabilistic model, overhead transmission lines.
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Mattar, Sarah Jamal, Mohammad Reza Kavian Nezhad, Michael Versteege, Carlos F. Lange y Brian A. Fleck. "Validation Process for Rooftop Wind Regime CFD Model in Complex Urban Environment Using an Experimental Measurement Campaign". Energies 14, n.º 9 (27 de abril de 2021): 2497. http://dx.doi.org/10.3390/en14092497.
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This research presents a validation methodology for computational fluid dynamics (CFD) assessments of rooftop wind regime in urban environments. A case study is carried out at the Donadeo Innovation Centre for Engineering building at the University of Alberta campus. A numerical assessment of rooftop wind regime around buildings of the University of Alberta North campus has been performed by using 3D steady Reynolds-averaged Navier–Stokes equations, on a large-scale high-resolution grid using the ANSYS CFX code. Two methods of standard deviation (SDM) and average (AM) were introduced to compare the numerical results with the corresponding measurements. The standard deviation method showed slightly better agreements between the numerical results and measurements compared to the average method, by showing the average wind speed errors of 10.8% and 17.7%, and wind direction deviation of 8.4° and 12.3°, for incident winds from East and South, respectively. However, the average error between simulated and measured wind speeds of the North and West incidents were 51.2% and 24.6%, respectively. Considering the fact that the upstream geometry was not modeled in detail for the North and West directions, the validation methodology presented in this paper is deemed as acceptable, as good agreement between the numerical and experimental results of East and South incidents were achieved.
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Wang, Zhao Kun, Jun Yi, Ming Yong Lai y Bao Ping Liu. "Copula-Based Security Assessment of Power Insulators Influenced by the Storm". Applied Mechanics and Materials 55-57 (mayo de 2011): 849–52. http://dx.doi.org/10.4028/www.scientific.net/amm.55-57.849.
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In this paper the model of Copula-based security assessment of power insulators under the impact of the storm is proposed. The model firstly analysis the daily average winds speed, the historical daily rainfall data to get the probability of wind speed and daily rainfall distribution. Then presents the model of security assessment of power insulators under the impact of wind and rainfall by considering not only the probability of relevance between the daily average wind speed and daily rainfall by using Copula join function, but also the combination of meteorological factors on the impact of power insulators security. This work was supported by the Key Scientific and Technological Project of Hunan Province of China (2008FJ1006).
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Krupar, Richard J., John L. Schroeder, Douglas A. Smith, Song-Lak Kang y Sylvie Lorsolo. "A Comparison of ASOS Near-Surface Winds and WSR-88D-Derived Wind Speed Profiles Measured in Landfalling Tropical Cyclones". Weather and Forecasting 31, n.º 4 (1 de agosto de 2016): 1343–61. http://dx.doi.org/10.1175/waf-d-15-0162.1.
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Abstract A set of velocity–azimuth display (VAD) wind speed profiles derived from coastal Weather Surveillance Radar-1988 Doppler (WSR-88D) systems was paired with Automated Surface Observing System (ASOS) 10-m standardized mean and nonstandardized gust wind speeds measured within 10 km of nearby WSR-88Ds. The goal was to formulate an appropriate methodology and empirical relationships to estimate overland near-surface wind conditions in landfalling tropical cyclones (TCs) using VAD tropical cyclone boundary layer (TCBL) lower-tropospheric wind measurements. A total of 17 TCs and seven ASOS/WSR-88D sites were used to construct a unique comparative dataset. Four estimation methods including the log and power laws, mean and gust wind speed ratio (WSR) methods, and curve fitting with linear regression and polynomial fits were evaluated. Results from the evaluation show that WSR-88D site-specific linear regression equations using a VAD 0–200-m layer average wind speed and nonzero intercepts provided the most accurate predictions of the ASOS 10-m standardized mean wind speed. Results also show that a non-site-specific linear regression model using a VAD 0–500-m mean boundary layer (MBL) wind speed and nonzero intercept is 1.07% more accurate than using a single-gust WSR to predict ASOS 10-m nonstandardized gust wind speeds. Only 2.15% of the ASOS 10-m nonstandardized maximum 3-s gust wind speeds were found to exceed the VAD 0–500-m MBL wind speed, indicating that the VAD 0–500-m MBL wind speed represents a viable source of momentum available for transport to the surface in the form of a gust.
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Paschmann, G., S. Haaland, B. Sonnerup y T. Knetter. "Discontinuities and Alfvénic fluctuations in the solar wind". Annales Geophysicae 31, n.º 5 (23 de mayo de 2013): 871–87. http://dx.doi.org/10.5194/angeo-31-871-2013.
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Abstract. We examine the Alfvénicity of a set of 188 solar wind directional discontinuities (DDs) identified in the Cluster data from 2003 by Knetter (2005), with the objective of separating rotational discontinuities (RDs) from tangential ones (TDs). The DDs occurred over the full range of solar wind velocities and magnetic shear angles. By performing the Walén test in the de Hoffmann–Teller (HT) frame, we show that 77 of the 127 crossings for which a good HT frame was found had plasma flow speeds exceeding 80% of the Alfvén speed at an average angular deviation of 7.7°; 33 cases had speeds exceeding 90% of the Alfvén speed at an average angle of 6.4°. We show that the angular deviation between flow velocity (in the HT frame) and the Alfvén velocity can be obtained from a reduced form of the Walén correlation coefficient. The corresponding results from the Walén test expressed in terms of jumps in flow speed and corresponding jumps in Alfvén speed are similar: 66 of the same 127 cases had velocity jumps exceeding 80% with average angular deviation of 5.8°, and 22 exceeding 90% of the jump in Alfvén speed, with average angular deviation 6.2°. We conclude that a substantial fraction of the 127 events can be identified as RDs. We present further evidence for coupling across the DDs by showing that, for most of the 127 crossings, the HT frame velocities, evaluated separately on the two sides of the DD, are nearly the same – a result required for RDs but not for TDs. We also show that the degree of Alfvénicity is nearly the same for the DDs and fluctuations in which the DDs are embedded. Whatever process causes deviations from ideal Alfvénicity appears to operate equally for the DDs as for the surrounding fluctuations. Finally, our study has established a unique relation between the strahl electron pitch angle and the sign of the Walén slope, implying antisunward propagation in the plasma frame for all 127 cases.
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Schramm, Matthew W., H. Mark Hanna, Matt J. Darr, Steven J. Hoff y Brian L. Steward. "Measuring Sub-second Wind Velocity Changes for Agricultural Drift One Meter Above the Ground". Applied Engineering in Agriculture 35, n.º 5 (2019): 697–704. http://dx.doi.org/10.13031/aea.12264.
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Abstract. Agricultural spray drift is affected by many factors including current weather conditions, topography of the surrounding area, fluid properties at the nozzle, and the height at which the spray is released. During the late spring/summer spray seasons of 2014 and 2015, wind direction, speed, and solar radiation (2014 only) were measured at 10 Hz, 1 m above the ground to investigate conditions that are typically encountered by a droplet when released from a nozzle on an agricultural sprayer. Measurements of wind velocity as the wind passed from an upwind sensor to a downwind sensor were used to evaluate what conditions wind may be most likely to have a significant direction or speed change which affects droplet trajectory. For two individual datasets in which the average wind speed was 3.6 and 1.5 m/s (8.0 and 3.4 mi/h), there exists little linear correlation of wind speed or wind direction between an upwind and downwind anemometer separated by 30.5 m (100 ft). The highest observed correlation, resulting from a 12-s lag between the upwind and downwind datasets, was 0.29 when the average wind speed was 3.6 m/s (8.0 mi/h). Correlations greater than 0.1 were only found for wind speeds exceeding 3 m/s. Using this lag time, it was observed that the wind direction 30 s into the future had a 30% chance to be different by more than 20° from current conditions. A wind speed difference of more than 1 m/s (2.2 mi/h) from current conditions [mean wind speed was 3.6 m/s (8.0 mi/h)] was observed about 50% of the time. Analyzing 36 days of the 2014 and 2015 spray season wind velocity data showed that the most variability in wind direction occurred with wind speeds below 2 m/s (4.5 mi/h). Greater wind direction variability occurred in the mid-afternoon with higher solar radiation. Keywords: Sprayers, Spray drift, Spray droplets, Turbulence, Wind effects.