Moderate Wind Research Articles

Numerical Investigation of Large Vehicle Aerodynamics Under the Influence of Crosswind

This paper presents a numerical analysis aimed at estimating the impact of crosswinds on the aerodynamics of large vehicles using ANSYS Fluid Flow and Static Structural, offering insights into the qualitative behaviour of trucks under typical traffic conditions. The cases analysed focus on airflow distribution when a truck, traveling at approximately 100 km/h, passes under a portal while exposed to varying crosswind intensities: weak, moderate, and strong lateral winds. A detailed examination of the truck and portal reveals significant interactions between the induced airflow patterns, affecting truck handling and stability. This is evidenced by shifts in velocity and pressure distributions, changes in drag coefficients, and variations in turbulent kinetic energy, all of which are analysed and discussed in this study.

VLT/MUSE Detection of Accretion/Ejection Associated with the Close Stellar Companion in the HT Lup System

The accretion/ejection processes in T Tauri stars are fundamental to their physical evolution, while also impacting the properties and evolution of the circumstellar material at a time when planet formation takes place. To date, the characterization of ongoing accretion processes in stellar pairs at 5–50 au scales has been challenging as high-angular resolution spectrographs are required to extract the spectral features of each component. We present the analysis of spectroscopic observations of the tight (160 mas, 25 au) T Tauri system HT Lup A/B, obtained with MUSE at the Very Large Telescope in 2021 March and July. We focus on constraining the accretion/ejection processes and variability of the secondary component HT Lup B by searching for accretion tracers by applying high-resolution spectral differential imaging techniques. We retrieve strong (signal-to-noise ratio > 5) Hα, Hβ, and [O i]λ6300 emission in both epochs. The Hα and Hβ line fluxes showcase high variability, with variations up to 200%–300% between epochs. The fluxes are consistent with accretion rates of 3× 10−9 M ⊙ yr−1 and 8 × 10−10 M ⊙ yr−1 for the first and second epochs, respectively. We attribute the increased accretion activity during the first night to a “burst-like” event, followed by a relaxation period more representative of the common accretion activity of the system. The [O i]λ6300 line profiles remain relatively similar between epochs and suggest ejection rates on the order of 10−9−10−10 M ⊙ yr−1, compatible with moderate disk wind emission. Our results also indicate that the accretion processes of HT Lup B are compatible with Classical T Tauri stars, unlike previous classifications.

The suppression of ocean waves by biogenic slicks.

Ocean waves are significantly damped by biogenic surfactants, which accumulate at the sea surface in every ocean basin. The growth, development, and breaking of short wind-driven surface waves are key mediators of the air-sea exchange of momentum, heat and trace gases. The mechanisms through which surfactants suppress waves have been studied in great detail through careful laboratory experimentation in quasi-one-dimensional wave tanks. However, the spatial scales over which this damping occurs in structurally complex surfactant slicks on the real ocean have not been resolved. Here, we present the results of field observations of the spatial response of decimetre- to millimetre-scale waves to biogenic surfactant slicks. We found that wave damping in organic material-rich coastal waters resulted in a net (spatio-temporally averaged) reduction of approximately 50% in wave slope variance relative to the open ocean for low to moderate wind speeds. This reduction of wave slope variance is understood to result in a corresponding reduction in momentum input to the wave field. This significant effect had thus far evaded quantification due in large part to the enormous range of scales required for its description-spanning the sea surface microlayer to the ocean submesoscale.

Tree Trimming Effects on 3-Dimensional Crown Structure and Tree Biomechanics: A Pilot Project

AbstractBackgroundAlong electric distribution corridors in urban-exurban landscapes, forest edges are susceptible to damage associated with storm events. Disturbances and management interventions designed to preempt their effects (e.g., tree trimming) alter characteristics of tree structure and morphology (e.g., branch and crown structure), which may be associated with tree failure and likelihood of associated infrastructure damage. This study assessed the relationship between 3-dimensional tree crown structure and tree biomechanics and characterized the effect of utility tree trimming on tree sway dynamics using terrestrial laser scanning (TLS).MethodsIn this study we extracted and analyzed measures of crown structure (i.e., crown asymmetry, crown area, total volume, crown diameter to height ratio, and crown evenness) for individual trees during leaf-off conditions before and after implementation of tree trimming and linked these measures to tree biomechanics data, to evaluate how commonly implemented trimming practices affect both tree sway frequency and displacement—important indicators of tree stability.ResultsResults illustrated the effects of common tree trimming practices on tree crown structure, but there were not consistent changes to tree movement characteristics directly following tree trimming across our 24 study trees. However, we found that the associated changes in crown structure through tree trimming affected tree displacement in moderate wind conditions. Additionally, we found there were no significant differences between frequencies across treatment types.ConclusionsThis pilot project lays the foundation for understanding the intricate relationship between 3-dimensional crown structure and tree biomechanics following roadside tree trimming.

Optical turbulence in the atmospheric surface layer at the Pamir Plateau Muztagh-ata site

Abstract In this paper, we conducted a detailed analysis of optical turbulence in the Atmospheric Surface Layer (ASL) at Muztagh-ata site during on-site testing. We utilized ultrasonic anemometers positioned on a 30-meter tower to collect and process data at five height levels, obtaining data from October 1, 2021 to the present. We investigated the behavior of optical turbulence parameters ($C_n^2$ and seeing ϵ) in the ASL. Nighttime $C_n^2$ primarily fluctuated in the range of 10−16 to 10−14, exhibiting an exponential decrease with height. During the day, it showed a h−0.82 dependency, while at night, it displayed a h−0.48 dependency. Additionally, we presented the distribution of seeing across different layers within the ASL, showing a gradual decrease with increasing height, with a median seeing of 0.24 arcseconds at nighttime and 0.48 arcseconds at daytime between 6-30m. We investigated the relationship between surface temperature inversion, seeing in the ASL, and wind speed at the site. Our results show that under temperature inversion conditions, seeing significantly improves and is often accompanied by low to moderate wind speeds, while high wind speeds are usually associated with poorer seeing. Preliminary calculations and observational results, combined with the high altitude and unique geographical location, suggest that Muztagh-ata site has the potential to be an outstanding optical astronomical observatory in the western plateau of china.

Initiation and evolution of urban-induced precipitation under different background wind speeds: Roles of urban breeze circulation and cold pool

Urban-enhanced precipitation is often observed far downwind of cities, suggesting important roles of background wind. This study examines the impacts of background wind on the initiation and evolution of urban-induced precipitation through idealized ensemble large-eddy simulations with different initial background wind speeds of 0, 1, 2, 3, 4, and 5 m s−1. Without background wind, a strong urban breeze circulation (UBC) initiates a relatively large number of cumulus clouds in the urban area, which exhibit greater cloud top heights than those in the rural area. The early-initiated clouds do not produce precipitation but moisten the middle troposphere, assisting later-initiated clouds to develop into deep convective clouds and produce concentrated precipitation in the urban area. As the background wind speed increases, the UBC weakens. Also, the high-humidity area generated by early-initiated clouds is continuously advected away from the urban area. Consequently, the precipitation initiation is delayed as the background wind speed increases. Precipitating clouds are advected downwind and generate a cold pool, and updrafts are repeatedly produced at the downwind boundary of the cold pool. The downwind-advected clouds are fed by the newly produced updrafts, being a long-lived organized precipitation system that produces a considerable amount of precipitation in the downwind area. This feeding effect is most prominent for a moderate background wind (3 m s−1), causing the precipitation amount and duration to be maximized. For stronger background winds, precipitation is initiated by the mechanical lifting of the warm air of the urban boundary layer over the cool rural boundary layer around sunset.

Quantifying urban climate response to large-scale forcing modified by local boundary layer effects

Over the past two decades, the joint manifestation of global warming and rapid urbanization has significantly increased the occurrence of heatwaves and the formation of urban heat islands in temperate cities. Consequently, this synergy has amplified the frequency and duration of periods with tropical nights (TNs) in these urban areas. While the occurrences of such extreme events demonstrate irregular and nonlinear annual patterns, they consistently manifest a discernible rising decadal trend in local or regional climatic data. In urban regions situated amidst hilly or mountainous landscapes, changing wind directions—often associated with uphill or downhill thermal flows—profoundly impact the spread and dispersion of heat-related pollution, creating unique natural ventilation patterns. Using the Lausanne/Pully urban area in Switzerland as examples of hilly and lakeshore temperate cities, this study explores the influence of wind patterns and natural urban ventilation on the nonlinearity of recorded climatic data within an urban environment. This study integrates a mesoscale numerical weather prediction model (COSMO-1), a microscale Computational Fluid Dynamics (CFD) model, field observations, variational mode decomposition technique, and statistical analysis to investigate how wind speed and direction critically influence the nonlinearity of recorded long-term trends of extreme events, specifically focusing on the frequency and duration of TNs in lakeshore and hilly cities. The results strongly indicate a direct correlation between the frequency of TNs and the occurrence of specific moderate wind patterns. These wind patterns are exclusively captured by the microscale CFD model, unlike the mesoscale model, which neglects both urban morphology and complex hilly terrains. The impact of temporal and spatial variability of the wind field on long-term observations at fixed measurement stations suggests that caution should be exercised when relying on limited spatial measurement points to monitor and quantify long-term urban climate trends, particularly in cities located in complex terrains.

Optimization Study of a Tuned Mass Damper for a Large Monopile Wind Turbine

Passively tuned mass dampers (TMDs) are known to effectively mitigate the vibration of wind turbines. However, existing literature predominantly examines their application in damping vibrations of the tower or platform, overlooking the potential benefits of installing TMDs on the turbine blades themselves. This study investigates the impact of wind and wave loads on TMD damping effectiveness and proposes a comprehensive damping strategy involving TMDs installed in both the nacelle and the blades. The design optimized the mass and stiffness of these TMDs to enhance their performance. Results indicate that, as wind speeds increased from 12 m/s to 24 m/s, the power spectral density at the tower’s natural frequency (0.22 Hz) more than doubled. Notably, TMDs exhibited robust vibration damping capabilities under high wind speeds. Specifically, at wind speeds of 24 m/s, TMDs reduced anterior–posterior and lateral displacement at the tower top by 61.2% and 166.8%, respectively, when two TMDs were combined. Conversely, the study found that TMDs did not significantly improve vibration damping at lower to moderate wind speeds. This research underscores the importance of optimizing TMDs for high wind conditions to ensure wind turbine stability and mitigate potential vibration-related risks effectively under varying environmental loads, including wind and waves. It offers valuable insights for the refined design and deployment of TMDs in wind energy applications.

Dependence of dense filament frontogenesis in a hydrostatic model

In this study, a hydrostatic model - the Navy Coastal Ocean Model (NCOM) is used to analyze the temporal evolution of a cold filament under moderate wind (along / cross filament) and surface cooling forcing conditions. The experimental framework adhered to the setup used in large eddy simulations by Sulllivan and McWilliams (2018). For each forcing scenario, the impact of horizontal resolutions is systematically explored through varies model resolutions of 100 m, 50 m, and 20 m; and the influence of horizontal mixing is investigated by adjusting the Smagorinsky constant within the Smagorinsky horizontal mixing scheme. The role of surface gravity waves is also assessed by conducting experiments both with and without surface wave forcing.The outcomes of our study revealed that while the hydrostatic model is able to predict the correct characteristics/physical appearance of filament frontogenesis, it fails to capture the precise dynamics of the phenomenon. Horizontal mixing parameterization in the model was found to have marginal effect on frontogenesis, and the frontal arrest is controlled by the model's subgrid-scale artificial regularization procedure instead of horizontal shear instability. Consequently, higher resolution is corresponding to stronger frontogenesis in the model. Thus, whether the hydrostatic model can produce realistic magnitude of frontogenesis is purely dependent on the characteristic of the front/filament simulated and model resolution. Moreover, examination of the parameterized effect of surface gravity wave forcing through vertical mixing unveiled a limited impact on frontogenesis, suggesting that the parameterization falls short in representing the real physics of wave-front interaction.

Potential processes leading to winter reddening of young Douglas-fir Pseudotsuga menziesii Mirb. Franco. in Europe

Key messageWinter reddening of young Douglas-fir (Pseudotsuga menziesii Mirb. Franco), triggered by large thermal fluctuations in late winter, is a critical problem for European forestry. A literature review identified certain climatic conditions that are characteristic of ‘reddening’ years, including warm daily temperatures, high daily temperature amplitude, low relative humidity, moderate wind speeds, as well as the occurrence of freeze-thaw cycles with cold night temperatures.By describing the triggering environmental and stand factors, we propose three hypotheses for the physiological processes leading to winter reddening, namely (i) hydraulic failure due to winter drought stress, (ii) photo-oxidative stress in shade-acclimated trees, and (iii) early cold deacclimation during warm periods.i) Low soil temperature, by reducing root water uptake, combined with anticyclonic conditions, by increasing water losses, can induce hydraulic failure in the xylem. Hydraulic failure may be further accelerated by night frosts.ii) Winter reddening can occur when low temperature and high irradiance coincide, disrupting photostasis. Overwhelming of winter photo-protection may lead to photodamage and subsequent reddening.iii) Warm periods, by inducing cold deacclimation, make trees susceptible to frost damage.Finally, the three processes may interact under atypical anticyclonic conditions in late winter (e.g. cold or dry soils, warm days, high irradiance and/or freezing nights). Indeed, trees under water stress would develop a higher sensitivity to freezing night and photooxidative stress. We therefore proposed mitigation actions to avoid exposing trees to stressful conditions based on e.g. stand characteristics, understorey vegetation and planting.

Technological Limit of Solar Concentration Technique Applied to Hybrid Photovoltaic-Thermal Solar Collector Equipped with Thermoelectric Generator Incorporating Ternary Nanofluid

Abstract This paper aims to explore the technological limits of the synergy between the solar concentration technique, facilitated by a parabolic concentrator, and the thermoelectric effect induced by a thermoelectric generator (TEG) within a PV/T, incorporating a ternary nanofluid (Cu-Al2O3-MWCNT/Water). Each component of the CPV/T-TEG is subject to energy balance equations, and the Runge Kutta fourth-order method is employed to solve the resultant mathematical model. The effects of the concentration ratio CR, the mass flow rate ṁ, and the nature of the heat transfer fluid (HTF) on the performance of the system are scrutinized. The simulations are carried out under the meteorological conditions of Ain Salah city in southern Algeria for a moderate wind velocity. The results show better performance when operating ternary nanofluid compared to other HTFs. Moreover, the outcomes indicate that by using a 2% volume fraction of nanoparticles of ternary nanofluid, the thermal output, electrical yield, and thermoelectric production reach enhancements of 14.55%, 11.18%, and 22.64%, respectively. Incorporating the solar concentrator resulted in 3.54 and 5.88 times increase in electrical and thermal powers, respectively. With the growths in ṁ, the temperature of the PV decreases by 53°, and the electrical efficiency improved by 34.52%. Correlations encompassing the concentration ratio and mass flow rate for various types of heat transfer fluids are established to predict the technological limits of CPV/T-TEG systems under the meteorological conditions specific to Ain Salah.

The exosphere of Mars can be tracked by a high-spectral resolution telescope, such as the Line Emission Mapper

Abstract Mars provides our local analogue for unmagnetized terrestrial planets and is thus key to understanding the habitability of exoplanets. The lack of a global magnetic field means that the atmosphere interacts directly with the solar wind, causing significant loss of the atmosphere. While in situ measurements provide a wealth of detailed local information, they are limited in deriving the global picture. In contrast, remote X-ray observations can provide important global instantaneous coverage over multiple seasons and sampling different solar wind. Previous XMM-Newton observations have detected significant flux via the solar wind charge exchange emission (SWCX) mechanism from an extended planetary halo, and from atmospheric fluorescence. In contrast, Chandra observations only detected a low-luminosity disk and a faint halo. It is postulated that these observational differences are due to transient solar wind with increased heavy ion fractions. Here, we present simulated spectra for the proposed NASA mission Line Emission Mapper, of both halo and disk regions, under quiet and transient solar wind. We show that even under moderate solar wind conditions, both SWCX and fluorescence emission lines are readily detected above the background, providing new insights into the loss of planetary atmospheres and the molecular composition of less well-characterised atmospheric abundances.

Observed Diurnal Cycles of Near‐Surface Shear and Stratification in the Equatorial Atlantic and Their Wind Dependence

AbstractThe diurnal cycles of near‐surface velocity and temperature, also known as diurnal jet and diurnal warm layer (DWL), are ubiquitous in the tropical oceans, affecting the heat and momentum budget of the ocean surface layer, air‐sea interactions, and vertical mixing. Here, we analyze the presence and descent of near‐surface diurnal shear and stratification in the upper 20 m of the equatorial Atlantic as a function of wind speed using ocean current velocity and hydrographic data taken during two trans‐Atlantic cruises along the equator in October 2019 and May 2022, data from three types of surface drifters, and data from Prediction and Research Moored Array in the Tropical Atlantic (PIRATA) moorings along the equator. The observations during two seasons with similar mean wind speeds but varying surface heat fluxes reveal similar diurnal jets with an amplitude of about 0.11 m s−1 and similar DWLs when averaging along the equator. We find that higher wind speeds lead to earlier diurnal peaks, deeper penetration depths, and faster descent rates of DWL and diurnal jet. While the diurnal amplitude of stratification is maximum for minimal wind speeds, the diurnal amplitude of shear is maximum at 6 m depth for moderate wind speeds of about 5 m s−1. The inferred wind dependence of the descent rates of DWL and diurnal jet is consistent with the earlier onset of deep‐cycle turbulence for higher wind speeds. The DWL and the diurnal jet not only trigger deep‐cycle turbulence but are also observed to modify the wind power input and thus the amount of energy available for mixing.

A sequence of weather‐driven hydrodynamic events stimulates the formation of harmful algal blooms on an oligotrophic lake

AbstractHarmful algal blooms (HABs) are common in many eutrophic lakes and frequently associated with nutrient excesses, warm waters, and calm conditions. While HABs can also occur in oligotrophic waterbodies, bloom‐stimulating factors remain elusive for these ecosystems. Here, using a high‐frequency sensor platform supported by hydrodynamic modeling, we document a clearly linked sequence of three hydrodynamic events that immediately preceded each HAB event on Skaneateles Lake, NY during 2018. HABs were first preceded by interactions between internal waves in the thermal structure of the lake with the northern slope of the lakebed. These interactions disturbed sediments resulting in upwelling of nutrient‐rich sediment and possibly cyanobacterial cells into the lower water column. Next, moderate winds stimulated Langmuir circulation which facilitated the transport of material from the lower water column to well‐lit surface waters. Finally, the sequence culminated with a calm wind period, which is often classically associated with surface HAB formation. While individual steps in this sequence occurred independently and repeatedly throughout the year, the complete sequence occurred only eight times, immediately preceding each of the eight documented HABs. We empirically derive thresholds for and timing of the sequence to independently predict HAB occurrence and elevated cyanobacteria levels in the lake. The discovery of this specific and repeated event sequence and the identified thresholds provides the potential for forecasting of HABs days in advance. Ongoing climate change impacts, including increasing water column thermal stratification and changing wind speeds may alter the frequency, timing, and duration of this sequence and consequent HAB formation.

3D aeronomy of two mini-neptunes in the HD 63433 system and their in-transit absorption in Ly α and metastable He i lines

ABSTRACT The numerical simulation of the HD 63433 system is performed with the aim to study upper atmospheres of two mini-Neptunes, planets b and c, interacting with the stellar wind of the parent star. The obtained results demonstrate that both exoplanets form the extended envelopes with strong supersonic outflows. The synthetic absorption profiles in the Ly α line show that under moderate stellar wind conditions, similar to those of the normal solar wind, the energetic neutral atoms contribute to the absorption in the high-velocity blue wing of the line at a level of tens per cent. The absorption in metastable helium He i(23S) line appears rather weak and below the detection limit by current instruments. An important feature revealed by the simulations is that the tail of escaping atmospheric material of the inner planet disturbs the stellar wind at orbital location of the outer planet and might, therefore, affect its observation in Ly α line.

Revealing the influence of wind vortex shedding on the stressed-strained state of steel tower structures with solid cross-section

This work investigated the effect of vortex shedding during the action of wind on tower structures with a solid cross-section. Failure to take into account this influence, together with the manifestation of the phenomena of physical wear of structures during long-term operation, can lead to building accidents. The object of the research are tower structures with a solid cross-section, which are widely used in modern infrastructure ‒ advertising pylons with a transparent advertising structure with a height of about 12, 22, 25 m, and a flagpole with a height of 48 m. The most frequent manifestations of oscillations according to the first natural frequency and shape have been considered, which occur even with moderate winds and when a large number of oscillation cycles occur. In this work, the number of oscillating cycles per year was determined and estimated based on the archive of meteorological observations. It was found that the number of oscillating cycles due to the action of wind excitation for the example of the structures under study is from 2.6 to 14.4 million per year, which requires the mandatory limitation of stresses in the parts of structures during the design to enable their durability. The magnitude of forces from vortex shedding for the studied structures ranges from 2.9 to 43.5 % of the forces caused by the influence of the frontal wind, depending on the height of the structure. Thus, it was found that the influence of vortex shedding is very insignificant for structures up to 12–15 m high and increases for structures 20 m and higher. Rational forms of the cross-sections of structures were established to reduce the influence of vortex shedding ‒ these are cross-sections of a circular and a cross-section close to it. In a general formulation, these are sections for which peak stresses relative to forces in one plane fall into the neutral zone for stresses from forces in another plane. Recommendations have been also given on the simultaneous consideration of forces from the action of frontal wind on the structure and vortex shedding since both manifestations of wind action on tower structures cannot be separated

Analysis of tower structure for fatigue taking into account wind vortex shedding

Vortex shedding is manifested in all tower structures with a solid or lattice cross-section with relatively equal width and depth of the cross-section. The phenomenon is associated with the alternate breakdown of vortices from the edges of the structure, which cause it to oscillate under the influence of inertial masses in a plane perpendicular to the wind. The main condition for the manifestation of vortex shedding is the action of wind with a speed exceeding a certain critical one. As shown by calculations of a real tower structure, oscillations according to the first natural frequency and shape occur already under the influence of a moderate wind. This requires attention, assessment of the number of oscillation cycles and the implementation of criteria for taking into account the combined effect of frontal wind and vortex shedding on the structure and calculation of the structure for endurance. The paradox is that this phenomenon is not widely known in engineering practice, and instructions on the mandatory calculation of structures for vortex excitation appeared only with the implementation of amendment 2 to DBN B.1.2-2:2006 "Loads and influences. Design norms" in 2020. In this analyzed state of research on this issue, an available method for calculating vortex excitation, introduced in EN 1991-1-4:2005, is presented. The calculation and analysis of the McDonald's advertising totem with a height of 25.575 m, implemented in Kyiv in 2016, was performed. Calculations showed that this structure is characterized by oscillations due to vortex shedding. From the available sources of meteorological data, an approximate number of oscillation cycles was determined, criteria for calculating the structure's durability were determined, and generalizations were made that can be applied to all structures. In particular, it is pointed out the need to limit stresses beyond the endurance limit in two ranges - parametric resonance from the frontal wind, and sign-changing cyclic oscillations from vortex excitation. An analysis of the effective cross-sections and effective structural forms of building details when working under the action of a frontal wind with vortex shedding was carried out.

The role of topography on the local circulation and formation of fog at Perth Airport

Perth Airport is located on a coastal plain in the south-west of Australia, with the Indian Ocean to the west and the Darling Scarp running approximately parallel to the coast to the east. On average, there are approximately nine fog events per year at the airport, typically occurring during the cooler months in the early morning hours. Onshore winds bringing moisture from the Indian Ocean can combine with nocturnal cooling in stable atmospheres to encourage fog formation. A previous climatological study of fog at Perth Airport found that the majority of events had north to north-easterly 10-m winds at fog onset time. Two case studies are presented to gain a better understanding of the physical processes associated with the north to north-easterly near-surface flow and their influence on the development of fog. The hypothesis is that the escarpment is blocking the moist environmental flow, resulting in light northerly near-surface winds. This was tested through numerical experiments including altered terrain. The main finding from the case studies was that the northerly winds stem from a blocking of the airmass in the lower level of the atmosphere by the Darling Scarp in moderate wind situations. During calm or very light wind occasions, the winds below the surface inversion level can tend northerly regardless of topography. The trapped airmass and light winds in the near surface layer in combination with nocturnal surface cooling and moisture from the environmental flow, create conditions favourable for the development of fog at Perth Airport.

Enhanced energy extraction from wind driven PMSG using digital twin model of battery charging system

The pressing need to meet sustainability and climate objectives has prompted a call for expanding the use of renewable energy sources, improving the intelligence and flexibility of electricity grids, and increasing the adoption of electric vehicles and other electricity-powered products. In light of their numerous benefits, widespread electrification and digital technologies can form the basis of energy and climate policy. This research presents an innovative biased transformer and digital twin battery model to support the wind energy based electric vehicle battery charging system. During periods of low and moderate wind, the biased transformer is utilized to increase the voltage for charging electric vehicles. A digital twin of the battery system creates a window into battery charging and aging levels by evaluating the data gathered based on internal resistance. Furthermore, the State of Charge estimation model and different internal resistance estimation algorithms are also exploited. A novel method for precise State of Charge (SOC) estimation in third-gen battery models is presented, integrating Collaborative Gradient Boosting and Adaptive Extended Kalman Filter (AEKF). This approach, implemented in MATLAB Simulink, combines machine learning and adaptive filtering, enhancing accuracy and adaptability for efficient battery management. The functionalities and resilience of both hardware and software of the proposed system are validated under field operation.

Data-driven met-ocean model for offshore wind energy applications

In recent years, the global transition towards green energy, driven by environmental concerns and increasing electricity demands, has remarkably reshaped the energy landscape. The transformative potential of marine wind energy is particularly critical in securing a sustainable energy future. To achieve this objective, it is essential to have an accurate understanding of wind dynamics and their interactions with ocean waves for the proper design and operation of offshore wind turbines (OWTs). The accuracy of met-ocean models depends critically on their ability to correctly capture sea-surface drag over the multiscale ocean surface—a quantity typically not directly resolved in numerical models and challenging to acquire using either field or laboratory measurements. Although skin friction drag contributes considerably to the total wind stress, especially at moderate wind speeds, it is notoriously challenging to predict using physics-based approaches. The current work introduces a novel approach based on a convolutional neural network (CNN) model to predict the spatial distributions of skin friction drag over wind-generated surface waves using wave profiles, local wave slopes, local wave phases, and the scaled wind speed. The CNN model is trained using a set of high-resolution laboratory measurements of air-side velocity fields and their respective surface viscous stresses obtained over a range of wind-wave conditions. The results demonstrate the capability of our model to accurately estimate both the instantaneous and area-aggregate viscous stresses for unseen wind-wave regimes. The proposed CNN-based wall-layer model offers a viable pathway for estimating the local and averaged skin friction drag in met-ocean simulations.