High Turbulence Research Articles

Inertial particles in a turbulent/turbulent interface

Turbulent interfaces are ubiquitous in the nature and in many important canonical flows (wakes, jets, mixing layers, boundary layers). In nature, the sharp edges of atmospheric clouds are defined by a turbulent/non-turbulent interface, where the droplet-laden turbulent cloud interior mixes with the unladen outer air. This study presents statistics of sub-Kolmogorov-scale inertial particles, in a parameter range representative of cloud droplets, in a sheared turbulent–turbulent interface. The study focuses on the effect of the inhomogeneous turbulent field on the particles’ clustering properties and settling velocity modification. Wind tunnel experiments were carried out in a well-characterised facility where a grid containing 81 independent gas/liquid injectors generates both high intensity turbulence and a field of small inertial droplets. These atomisers, located at the entrance of the test section, contribute significantly to the carrier phase turbulence and are used to create the sheared turbulent/turbulent interface. Selecting which atomisers are on or off enables us to control the mean velocity profile and the gradient of turbulent intensity through the tunnel cross-section. The resulting carrier flow is characterised by a gradient of mean velocity, turbulent velocity rms, and a sharp interface separating two regions with different turbulent scales. Particles’ velocities and diameters were measured with a Phase Doppler Particle Analyser, at closely-spaced positions across the turbulent interface. In agreement with previous experimental studies on the topic, particles are shown to be transported from the turbulent side, with higher turbulence intensity, to the low-intensity side by large-scale-energetic eddies. Newly observed in our results is an enhancement of particle preferential concentration and settling velocity in the sheared interface region, caused by the interaction between particle trajectories and turbulent structures of different sizes.

Effect of inlet flow turbulence on hydro–acoustic coupling and flame–vortex interactions in a premixed dump combustor

The present work examines the effect of inlet flow turbulence on the flame–vortex modulations, hydro–acoustic coupling and recirculation zone dynamics at the onset of instability. The flow turbulence intensity varied using a custom-designed turbulence generator with different slot-width blockage plates placed upstream to the nominal flame-stabilization zone. The high-speed recordings of the CH*/OH* chemiluminescence and particle image velocimetry are used to deduce the relation between the flame–acoustic, flame–vortex and hydrodynamic–acoustic features during the unsteady combustion. The bifurcation analysis map revealed the effect of high inlet flow turbulence on postponing the onset of instability to higher inlet flow parameters. The initial observations showed potential changes in the acoustic behaviour and dynamical state of premixed turbulent combustion with an increase in inlet flow turbulence. The spatial Rayleigh index map illustrates a significant change in the acoustic driving region at high inlet flow turbulence based on the flame stabilization, heat release zone and flame–acoustic modulation in the shear layer and recirculation zone. The velocity spectral analysis and dynamic mode decomposition (DMD) spectrum suggested a correlation between the acoustic modulation and hydrodynamic instabilities, resulting in higher heat release rate oscillations. The high inlet flow turbulence modulates the vertical flapping motion of the flame front and flame roll-up in the recirculation region as evident by DMD spectrum and spatial modes. The flame–vortex dynamics during the dynamic transition events showed that the high inlet flow turbulence influenced the vortex shedding along the shear layer and recirculation zone dynamics. At low turbulence intensity, the vortex, in turn, supports the bulk flame movement through the induced velocity, which interacts with the free stream to create regions of low velocity. In contrast, the vortex in the shear layer and flame resides along the shear layer at higher turbulence. The paper concludes that at higher inlet flow turbulence, the recirculating flame reduces the hydro–acoustically modulated flow velocity fluctuations, which significantly affect the upstream flame propagation propensity.

Implementation of Anti-Abrasion Grid in Sumsel-5 580 t/h CFB Boiler (Reliability and Performance Evaluation)

CFB Boiler operated with turbulence model and fast fluidization. This model regime gives CFB boiler great heat distribution and increase boiler efficiency. Disadvantage of regime is due boiler furnace feed with coal, sand and limestone as bed material. Bed material with the high velocity and turbulence regime can be harmful for water and steam tube inside of furnace. Operational challenges such as abrasion and abrasion of boiler components will significantly affect their efficiency and increase possible force shutdown because of boiler tube leakage. This research investigated the implementation of anti-abrasion grids perpendicular to water wall tubes of Sumsel-5 CFB Boiler, installed horizontally and vertically to mitigate abrasion and enhance overall performance. The result showed that anti-abrasion grid installation could increase the lifespan of the CFB boiler, reduce the abrasion rate by more than 50%, and lead to enhanced boiler performance by 0,4%. Anti-abrasion grid installation could also reduce the maintenance cost due to water wall tube repair.

Accurate Method for Estimating Wall-Friction Based on Analytical Wall-Law Model

A novel method is proposed for accurately determining the local wall friction through the near-wall measurement of time-average velocity profile in a Type-A turbulent boundary layer (TBL). The method is based on the newly established analytical wall-law in Type-A TBL. The direct numerical simulations (DNS) data of turbulence on a zero-pressure-gradient flat-plate (ZPGFP) is used to demonstrate the accuracy and the robustness of the approach. To verify the reliability and applicability of the method, a two-dimensional particle image velocimetry (PIV) measurement was performed in a ZPGFP TBL with a low-to-moderate Reynolds number (Re). Via utilizing the algorithm of single-pixel ensemble correlation (SPEC), the velocity profiles in the ZPGFP TBL were resolved at a significantly improved spatial resolution, which greatly enhanced the measurement accuracy and permitted us to accurately capture the near-wall velocity information. The accuracy of the approach is then quantitatively validated for the high Reynolds number turbulence using the ZPGFP TBL data. The research demonstrates that the current method can provide the precise estimation of wall friction with a mean error of less than 2%, which not only possesses the advantage of its insensitivity to the absolute wall-normal distance of the measuring point, but also its capability of providing an accurate prediction of wall shear stress based on fairly sparse experimental data on the velocity profile. The current study demonstrates that the wall shear stress can be accurately estimated by a velocity even at a single-point either measured or calculated in the near-wall region.

Direct numerical simulations of pure and partially cracked ammonia/air turbulent premixed jet flames

Ammonia has been identified as a promising fuel to diminish greenhouse gas emission. However, ammonia combustion presents certain challenges including low reactivity and high NO emission. In the present study, three-dimensional direct numerical simulations (DNS) of ammonia/air premixed slot jet flames with varying Karlovitz numbers (Ka) and cracking ratios were performed. Three cases were considered, including two pure ammonia/air flames with different turbulence intensities and one partially cracked ammonia/air flame with high turbulence intensity. The effects of turbulence intensity and partial ammonia cracking on turbulence–flame interactions and NO emission characteristics of the flames were investigated. It was shown that the turbulent flame speed is higher for the flames with high turbulence intensity. In general, the flame displacement speed is negatively correlated with curvature in negative curvature regions, while the correlation is weak in the positive curvature regions for highly turbulent flames. Most flame area is consumed in negatively curved regions and produced in positively curved regions. It was found that the NO mass fraction is higher in the flame with partial ammonia cracking compared to the pure ammonia/air flames. The NO pathway analysis shows that the NH → NO pathway is enhanced, while the NO consumption pathway is suppressed in the partially cracked ammonia/air flame. The NO mass fraction is higher in regions of negative curvature than positive curvature. Interestingly, the NO mass fraction is found to be negatively correlated with the local equivalence ratio, which is consistent in both the DNS and the corresponding laminar premixed flames.

Asymmetry, Gap Opening, and a High Accretion Rate on DM Tau: A Hypothesis Based on the Interaction of Magnetized Disk Wind with Planets

Over 200 protoplanetary disk systems have been resolved by the Atacama Large Millimeter/submillimeter Array (ALMA), and the vast majority suggest the presence of planets. The dust gaps in transition disks are considered evidence of giant planets sculpting gas and dust under appropriate disk viscosity. However, the unusually high accretion rates in many T Tauri stars hosting transition disks challenge this theory. As the only disk currently observed with high turbulence, the high accretion rate (∼10−8.3 M ⊙ yr−1) observed in DM Tau indicates the presence of strong turbulence within the system. Considering the recent theoretical advancements in magnetized disk winds are challenging the traditional gap-opening theories and viscosity-driven accretion models, our study presents a pioneering simulation incorporating a simplified magnetized disk wind model to explain the observed features in DM Tau. Employing multifluid simulations with an embedded medium mass planet, we successfully replicate the gap formation and asymmetric structures evident in ALMA Band 6 and the recent Karl G. Jansky Very Large Array 7 mm observations. Our results suggest that when magnetized disk wind dominates the accretion mode of the system, it is entirely possible for a planet with a medium mass to exist within the gap inside 20 au of DM Tau. This means that DM Tau may not be as turbulent as imagined. However, viscosity within the disk should also contribute a little turbulence to maintain disk stability.

Predictive analytics on artificial intelligence in supply chain optimization

AI-powered predictive analytics is among the most important ways of optimizing supply chains. This paper on AI-powered predictive analytics will address improving the competitiveness and effectiveness of supply chain operations. Nevertheless, current methods are not always scalable or adaptable to complex supply networks and changing market environments. Therefore, this paper posits that Supply Chain Optimization using Artificial Intelligence (SCO-AI) systems can help with these concerns. SCO-AI employs real-time data analysis and advanced machine learning algorithms which results to reduced response time, enhanced logistics route optimization, improved demand planning as well as real-time inventory control. Thus, the idea herein suggested fits smoothly into existing supply chain frameworks for data-driven decisions that make companies remain agile in ever-changing market dynamics. SCO-AI implementation has seen significant improvements in inventory turnover rate, rates of on-time delivery as well as overall supply chain costs. In this period of high business turbulence, such kind of research builds up the robustness of a given supply chain while at the same time minimizing operational risks by means of simulations and case studies

Direct numerical simulation of transition under free-stream turbulence and the influence of large integral length scales

Under the action of free-stream turbulence (FST), elongated streamwise streaky structures are generated inside the boundary layer, and their amplitude and wavelength are crucial for the transition onset. While turbulence intensity is strongly correlated with the transitional Reynolds number, characteristic length scales of the FST are often considered to have a slight impact on the transition location. However, a recent experiment by Fransson and Shahinfar [J. Fluid Mech. 899, A23 (2020)] shows significant effects of FST scales. They found that, for higher free-stream turbulence levels and larger integral length scales, an increase in the length scale postpones transition, contrary to established literature. Here, by performing well-resolved numerical simulations, we aim at understanding why the FST integral length scale affects the transition location differently at low- and high turbulence levels. We found that the integral length scales in Fransson and Shahinfar's experiment are so large that the introduced wide streaks have substantially lower growth in the laminar region, upstream of the transition to turbulence, than the streaks induced by smaller integral length scales. The energy in the boundary layer subsequently propagate to smaller spanwise scales as a result of the nonlinear interaction. When the energy has reached smaller spanwise scales, larger amplitude streaks results in regions where the streak growth are larger. It takes longer for the energy from wider streaks to propagate to the spanwise scales associated with the breakdown to turbulence, than for those with smaller spanwise scales. Thus, there is a faster transition for FST with lower integral length scales in this case.

Enhancing the Stability of Small Rescue Boats: A Study on the Necessity and Impact of Hydraulic Interconnected Suspensions

Aiming to solve the problem that existing small rescue boats cannot realize the effective and stable rescue of human lives under high sea turbulence conditions, this paper proposes a parallel decoupled hydraulic interconnected suspension system for actual sea state. The system dynamics model is established, and its damping characteristics are analyzed by joint simulation. The results show that compared with the truss-type rescue ship, the suspension system can improve the transverse rocking resistance by 81.5% and the longitudinal rocking resistance by 25.0%, and the system has excellent transverse rocking resistance.

ANALYSIS OF THE USE OF BLOCKCHAIN AND SMART CONTRACT TECHNOLOGIES FOR MANAGEMENT AUTOMATION AND ENSURING BUSINESS RESILIENCE

Increasing competition, the need to enhance efficiency and transparency of business processes, as well as the requirements to ensure the security and reliability of operations, demand new tools and approaches for automating management and ensuring the sustainability of the enterprise. Currently, it is blockchain and smart contract technologies that are opening up vast opportunities for this. Therefore, the research is aimed at a comprehensive analysis of the features and directions of using blockchain and smart contract technologies for automating management and ensuring the sustainability of the enterprise. Within the research, it has been proven that the use of blockchain and smart contract technologies creates a flexible and secure process for developing conditions and strategies that allow an enterprise to function effectively and remain capable of ensuring its own progressive development even in conditions of high stochasticity, economic turbulence, or crises. It is concluded that among the main directions where the use of blockchain technologies for ensuring enterprise resilience is worthwhile, the following should be highlighted: supply chain management, balanced management, security management, and basic risk management, as well as managing relationships with customers and partners. In unity, these outlined directions establish the principles of automating enterprise management, enhance its ability to function effectively, and direct its progressive development. It is concluded that among the main directions where the use of smart contracts for ensuring enterprise resilience is beneficial, the following should be highlighted: access and security management, remote tracking of resource utilization, automation of production and commercial processes, improvement of customer service, and management of data processing workflows. In unity, these outlined directions establish the principles of enterprise management automation, guiding and expanding the enterprise's capabilities for progressive development. In the context of ensuring enterprise resilience, the goal of applying smart contracts and blockchain technologies can vary. However, the use of these outlined technological solutions should guarantee the enterprise's ability to withstand external and internal influences.

Building entrepreneurial resilience during crisis using generative AI: An empirical study on SMEs

Recently, Gen AI has garnered significant attention across various sectors of society, particularly capturing the interest of small business due to its capacity to allow them to reassess their business models with minimal investment. To understand how small and medium-sized firms have utilised Gen AI-based tools to cope with the market's high level of turbulence caused by the COVID-19 pandemic, geopolitical crises, and economic slowdown, researchers have conducted an empirical study. Although Gen AI is receiving more attention, there remains a dearth of empirical studies that investigate how it influences the entrepreneurial orientation of firms and their ability to cultivate entrepreneurial resilience amidst market turbulence. Most of the literature offers anecdotal evidence. To address this research gap, the authors have grounded their theoretical model and research hypotheses in the contingent view of dynamic capability. They tested the research hypotheses using cross-sectional data from a pre-tested survey instrument, which yielded 87 useable responses from small and medium enterprises in France. The authors used variance-based structural equation modelling with the commercial WarpPLS 7.0 software to test the theoretical model. The study's findings suggest that Gen AI and EO have a significant influence on building entrepreneurial resilience as higher-order and lower-order dynamic capabilities. However, market turbulence has a negative moderating effect on the path that joins entrepreneurial orientation and entrepreneurial resilience. The results suggest that the assumption that high market turbulence will have positive effects on dynamic capabilities and competitive advantage is not always true, and the linear assumption does not hold, which is consistent with some scholars' assumptions. The study's results offer significant contributions to the contingent view of dynamic capabilities and open new research avenues that require further investigation into the non-linear relationship of market turbulence.

Experimental and numerical study of improving flow and heat transfer in a serpentine cooling channel with topology-optimized TPMS porous structures

Serpentine cooling channels have been employed in various industrial applications to control the heat loads in the system by increasing heat transfer while lowering the total pressure loss. As additive manufacturing (AM) enables the fabrication of complex structures, more sophisticated cooling models have been proposed to improve the thermal performance of the serpentine channel. This work designs a high-performance serpentine cooling channel based on topology optimization and triply periodic minimal surface (TPMS). The transient liquid crystal thermography (TLC) is used to reveal the endwall heat transfer characteristics of the optimized serpentine channel infilled with the Diamond TPMS topology within the Reynolds number of 10,000–40,000. The overall and local flow structures are revealed by numerical simulation, and the results are compared with the baseline serpentine channel. The experimental results show that at the Reynolds number of 10,000, the topology-optimized model with the Diamond structure shows a higher wetted-area averaged Nusselt number in the second pass by 70.7 % while reducing the total pressure loss by 19.2 %, compared to the smooth channel. Within the studied Reynolds numbers, the heat transfer enhancement in the second pass is 2.30–2.39 times relative to a smooth channel. The numerical results show that the topology-optimized model significantly improves the thermal performance by up to 82.7 % compared to the baseline because the flow recirculation and the regions of low heat transfer are eliminated. The optimized channel also mitigates the negative effect of the Dean's vortices while keeping high turbulence and improving flow and heat transfer uniformity.

Ignition energy, explosion flame propagation, and particle movement process of coal dust cloud in vertical Hartmann tube

To discuss the ignition energy, explosion flame propagation, and particle movement process of coal dust in vertical glass tube, experimental analysis and numerical simulation methods are used to carry out research. The experimental research results show that the optimal ignition delay time is 1 s, under this condition, the dust cloud near the ignition electrode has the highest turbulence, making it easier to ignite. When the dust cloud mass concentration is 2500 g/m3, the ignition energy is the smallest, resulting in the highest risk of explosion. The simulation results show that the propagation speed of flame is 4 m/s, due to the small amount of suspended dust used, the intensity of the explosion is not significant. The further away from the explosion source, the more energy is lost, the lower the temperature of the flame. Within 30∼50 ms after the ignition, the temperature near the explosion source rapidly increases, from 900 K to 1300 K. During the period of 0.2–0.5 s after dust injection, most particles move upwards along the tube. At 1 s after the dust injection, most particles move downwards and gather near the ignition electrode, forming a suspended dust cloud that is easily ignited, which is consistent with the optimal ignition delay time of 1 s obtained from the experiment.

Role of turbulence in Dinophysis spp. growth, feeding, and toxin leakage in culture

Dinophysis, a mixotrophic dinoflagellate that is known to prey on the ciliate Mesodinium rubrum, and retain its chloroplasts, is responsible for diarrhetic shellfish poisoning (DSP) in humans and has been identified on all U.S. coasts. Monocultures of Dinophysis have been used to investigate the growth of Dinophysis species in response to variations in environmental conditions, however, little is known about the roles of system stability (turbulence) and mixotrophy in the growth and toxicity of Dinophysis species in the U.S.. To begin to address this gap in knowledge, culturing experiments were conducted with three species (four strains) of Dinophysis, that included predator-prey co-incubation (Dinophysis spp.+ M. rubrum) and prey-only (M. rubrum) flasks. Cultures were investigated for effects of low or high turbulence on Dinophysis spp. growth, feeding, and amounts of intra- and extracellular toxins: okadaic acid and derivatives (diarrhetic shellfish toxins, DSTs) and pectenotoxins (PTXs). Turbulence did not have a measurable effect on the rates of ingestion of M. rubrum prey by Dinophysis spp. for any of the four strains, however, effects on growth and particulate and dissolved toxins were observed. High turbulence (ε = 10−2 m2s−3) significantly slowed growth of both D. acuminata and D. ovum relative to still controls, but significantly stimulated growth of the D. caudata strain. Increasing turbulence also resulted in significantly higher intracellular toxin content in D. acuminata cultures (DSTs and PTXs), but significantly reduced intracellular toxin content (PTXs) in those of D. caudata. An increase in turbulence appeared to promote toxin leakage, as D. ovum had significantly more extracellular DSTs found in the medium under high turbulence when compared to the still control. Overall, significant responses to turbulence were observed, whereby the three strains from the “Dinophysis acuminata complex” displayed a stress response to turbulence, i.e., decreasing growth, increasing intracellular toxin content and/or increasing toxin leakage, while the D. caudata strain had an opposite response, appearing stimulated by, or more tolerant of, high turbulence.

Implications of Using Scalar Forcing to Sustain Reactant Mixture Stratification in Direct Numerical Simulations of Turbulent Combustion

A recently proposed scalar forcing scheme that maintains the mixture fraction mean, root-mean-square and probability density function in the unburned gas can lead to a statistically quasi-stationary state in direct numerical simulations of turbulent stratified combustion when combined with velocity forcing. Scalar forcing alongside turbulence forcing leads to greater values of turbulent burning velocity and flame surface area in comparison to unforced simulations for globally fuel-lean mixtures. The sustained unburned gas mixture inhomogeneity changes the percentage shares of back- and front-supported flame elements in comparison to unforced simulations, and this effect is particularly apparent for high turbulence intensities. Scalar forcing does not significantly affect the heat release rates due to different modes of combustion and the micro-mixing rate within the flame characterised by scalar dissipation rate of the reaction progress variable. Thus, scalar forcing has a significant potential for enabling detailed parametric studies as well as providing well-converged time-averaged statistics for stratified-mixture combustion using Direct Numerical Simulations in canonical configurations.

Investigation of the effect of free-stream turbulence on paired vertical-axis wind turbines using wind tunnel testing and an actuator-line model

The aerodynamic interaction of vertical-axis wind turbines (VAWTs) in paired configurations can be advantageous in wind farms. However, these turbines operate in the atmospheric boundary layer which is characterised by high turbulence and may also face high-turbulence levels associated with downstream wakes. Therefore, the main goal of this study is to explore the impact of turbulence intensity on the efficiency of paired VAWTs, employing a combination of wind tunnel experiments and an actuator-line model (ALM) integrated in a URANS-based OpenFOAM solver. The present ALM employs aerodynamic coefficients derived from experimental dynamic measurements conducted on a pitching aerofoil. The wind tunnel tests suggest that paired VAWTs operating in turbulent inflow can experience advantages arising from both the mutual aerodynamic interaction between them and the effect of turbulence on the aerodynamic conditions on their aerofoils. Additionally, the ALM sheds light on the mechanisms that contribute to the enhanced power output of isolated and paired VAWTs in turbulent inflow conditions.

Aerodynamic conditions measured at a rotor blade of large wind turbine prototype

In this paper we present high resolution pressure distributions measured on the surface of a rotor blade of an 8 MW offshore prototype. We investigate two time intervals of approximately 10 minute duration acquired in April 2022. During the first time interval the turbine is operated at rated power, during the second time interval the turbine is operated below rated power. We see a clear increase and decrease of pressure values on the pressure side and suction side of the rotor blade, respectively. Also, 1P frequency oscillations are found in all sensors except during idling state. We find a decreasing signal to noise ratio in these oscillations with increasing distance from leading edge towards trailing edge, indicating higher turbulence in the air flow. Additionally, pressure changes during pitching movements can be observed. These data present the first data set of pressure distribution measured over a longer time period on a state-of-the-art sized offshore wind turbine prototype and therefore, provide important input for model validation and further understanding of the aerodynamic conditions at a rotor blade.

Experimental and numerical investigation on the potential of wake mixing by dynamic yaw for wind farm power optimization

This study investigates open-loop dynamic yaw control as a strategy for enhancing wind farm performance through wake mixing. The focus is on understanding the potential for enhanced wake mixing under different turbulence intensities, and the mechanisms triggering mixing. Experimental tests are conducted using scaled wind tunnel experiments with two model wind turbines. The wake flow is analysed by large eddy simulations (LES). Dynamic yawing is prescribed by sinusoidally varying the yaw angle at different excitation frequencies. The study reveals that dynamic yaw control, particularly at low inflow turbulence, leads to increased wake mixing. The resulting enhanced wind farm power capture has a rather flat maximum around an optimal Strouhal number. This is in contrast to high inflow turbulence, where the effectiveness of the control strategy is significantly reduced. The meandering motion of the wake induced by dynamic yaw excitation is identified as the key mechanism for improved wake recovery.

Airborne wind energy systems flying optimal trajectories in turbulent wind using flight path tracking

Airborne Wind Energy Systems (AWES) consist of tethered wings harvesting power from the wind. Rigid-wing (aircraft) pumping-mode AWES are considered here: they generate power during the reel-out phase and consume a fraction of this power during the reel-in phase. Those devices fly complex trajectories that require advanced control strategies. In the present work, we aim to develop a Large Eddy Simulation (LES) framework and improve the fidelity of existing models. The toolbox AWEbox is used for reference trajectories generation and control. Here the device is operated with a closed-loop control using a 6-DOF aircraft model. The aircraft is modeled using an actuator line (AL) for the wing, and the effects of the control surface are incorporated using their geometry and lift slope. The AL-based model is used to assess the robustness of the nonlinear model predictive controller against turbulence and to compare the performance between idealized conditions in AWEbox and turbulent wind conditions in the LES. The controller demonstrates high efficiency in tracking the reference trajectory and extracting the maximum power, even at high turbulence levels.

Wind Turbine Loads in the Near Wake

This work is analyzing the the engineering wake models Frandsen and TNO for small inter-turbine distances. Therefore, loads generated by actuator line LES (AL-LES) wind fields will be compared with the loads generated by the mentioned engineering models. The results are checked for plausibility by comparing the current results with the available literature. Load comparisons for non-dimensional distances x/D ranging from 1.75 to 4 and for seven different wind speeds in order to consider the influence of the thrust coefficient were made. For each speed a low and a high turbulence intensity case is considered. Two latest generation turbines are investigated (one with a diameter of 138 m and one with a diameter of 175 m).Our studies reveal that the fatigue loads computed with the Frandsen and TNO model are conservative compared to the loads generated by AL-LES wind fields. The Wöhler averaged (m=10 and a sector of 120°) flap wise blade root bending moments are at least 150% higher for the TNO and Frandsen model compared to the loads generated by AL-LES wind fields for distances lower than 2.3D and C T values higher than 0.7. This indicates that current sector management rules applied by means of the results of the Frandsen and TNO model are too restrictive. A possible way to decrease the conservatism without posing at risk the structural integrity of the turbines is the following: The wake added turbulence intensity can be kept constant for regions in the parameter space with very high conservatism (e.g. for distances smaller than 2.3D and C T values higher than 0.7).