bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validation of a Lattice Boltzmann Solver Against Wind Turbine Response and Wake Measurements
Authors: Korb Henry , Asmuth Henrik , Ivanell Stefan 
Published: May 2023

Abstract
Two of the major limitations facing the adoption of large-eddy simulation (LES) to the industry today are a lack of validation against full-scale measurements and the high computational cost. The lattice Boltzmann method is an approach to conduct LES that is suitable for parallelization on graphics processing units, leading to reduction in energy-to-solution by multiple orders of magnitude compared to Navier-Stokes solvers. We validate the lattice Boltzmann solver VirtualFluids against the measurements published in the SWiFT benchmark and the results obtained with LES by the participants in the benchmark. We compare inflow, turbine response and wake quantities and show that our method yields similar results. While the other LES methods vary in the required energy by one order of magnitude, our methodology is always about one to two orders of magnitude more efficient. The benchmark allows for a comparison to a large number of models, however, the scale of the turbine is not representative of modern turbines and therefore important challenges of modern turbines, such as blade deflection, could not be validated.
Quantifying and clustering the wake-induced perturbations within a wind farm for load analysis
Authors: Lovera A. , Fekhari E. , Jézéquel B. , Dupoiron M. , Guiton M. , Ardillon E. 
Published: May 2023

Abstract
The main objective of the HIPERWIND project is to reduce the Levelized Cost Of Energy by controlling the uncertainties in a chain of numerical models simulating an offshore wind farm. This paper studies the wake-induced perturbations of the ambient wind conditions inside a wind farm. A theoretical floating offshore wind farm off the coast of South Brittany in France is considered as a test case, and a numerical model simulating the wake of this farm is exploited. This model gives an analytical prediction of wake deficit and added turbulence, also considering the influence of the floaters’ position due to mean wind forces. An uncertainty propagation on the wake model is performed, considering the multivariate joint distribution of ambient wind conditions as input. This results, for each turbine, in a wake-modified probabilistic distribution on the wind speed and turbulence intensity averaged over the rotor. A new approach for clustering these wake-modified distributions is proposed in this paper to regroup the wind turbines exposed to similar environmental conditions, leading to a similar structural response. This analysis is essential to ensure the practical feasibility of the reliability analysis of an overall project with the computational cost of aero-servo-hydro-elastic simulations of offshore wind turbines. Several methods classically used for clustering are compared. Finally, four clusters only are sufficient to represent the whole set of turbines in the wind farm.
Sensitivity of Lillgrund Wind Farm Power Performance to Turbine Controller
Authors: Troldborg N , Andersen S J 
Published: May 2023

Abstract
The impact of the choice of the individual wind turbine controller on the power production of a wind farm is studied by means of large eddy simulations (LES) combined with aero-servo-elastic actuator disc representations of the rotors. The investigation includes both two typical controllers for pitch-regulated variable speed wind turbines and a simplified control strategy based on tabulated rotor speed and pitch as a function of the average velocity at the rotor. The simulations show that the power output of the individual wind turbines is strongly affected by choosing either a standard or simplified control strategy when they operate in the deep wake of upstream turbines. On the other hand, the sensitivity to control strategy is less significant for wind directions where the effective stream-wise distance between the turbines is larger.
Proper Orthogonal Decomposition (POD) of the Wake Flow Field of a Model Wind Turbine and a Porous Disc under Different Freestream Turbulence Intensity Conditions
Authors: Öztürk Buğrahan , Hassanein Abdelrahman , Tuğrul Akpolat M , Abdulrahim Anas , Perçin Mustafa , Uzol Oğuz 
Published: May 2023

Abstract
The effects of freestream turbulence intensity on the wake development of a model wind turbine and a porous disc are investigated through Proper Orthogonal Decomposition (POD) analysis. The capability of porous discs for reproducing far-wake characteristics of a model wind turbine is examined through coherent structures both in the near-wake and far-wake regions. Instantaneous velocity fields are obtained through wake measurements using two-dimensional two-component particle image velocimetry (2D2C PIV). These velocity fields are considered snapshots of the spatial domain. Results show inherent differences between coherent structures of a model wind turbine and porous disc in the near-wake region, especially when the freestream turbulent intensity level is low. However, these differences reduce, and coherent structures become more comparable when the freestream turbulence intensity level is higher. It is shown that the first five streamwise components of POD modes are paired for the model wind turbine and the porous disc cases under high freestream turbulence intensity conditions in the far-wake region.
Near wake of the X-Rotor vertical-axis wind turbine
Authors: Bensason David , Sciacchitano Andrea , Ferreira Carlos 
Published: May 2023

Abstract
In the present study, the near wake of a novel vertical-axis wind turbine known as the X-Rotor is experimentally investigated. Particle image velocimetry is used to measure the phase-locked flowfield at several streamwise locations within the rotor’s volume of rotation. The results show a clear impact of coned blades on the streamwise and axial induction fields as well as the local presence of vorticity structures. A notable counteraction of the average expansion of the wake in the axial direction is observed stemming from the shed and tip vorticity of the coned blades. As a result, an axial contraction and radial expansion in the wake can be observed across several phase and cross-stream combinations as well as a consistent asymmetry in streamwise flow. These results encourage the development and validation of numerical models that can account for the three-dimensional induction field of the X-Rotor as well as a further study into the far wake and farm-level installation of vertical-axis wind turbines.
Full-scale validation of optimal axial induction control of a row of turbines at Lillgrund wind farm
Authors: Bossanyi Ervin , Larsen Gunner C. , Pedersen Mads M. 
Published: May 2023

Abstract
We present a full-scale validation study of an optimal power open-loop wind farm control schedule (WFCS) using a full row of turbines (Row-A) at the Lillgrund offshore wind farm as the demonstration case. The derived WFCS is conditioned on the ambient wind speed and wind direction. The WFCS’s are developed using the DNV and DTU numerical models LongSim and Fuga. Prior to implementation, the developed optimal controllers are tested by comparing LongSim results, based on Fuga optimized input, with Fuga optimized results and vice versa. These models are very different in their nature — Fuga being a linearized RANS CFD solver, and LongSim being based on a range of engineering wake models and allowing for unsteady wind farm flow modelling — but nevertheless the overall computed Row-A power gains are reasonably similar. This gives confidence to the developed WFCS’s, even though the two models predict significantly different distributions of the power gains over wind speeds and directions. Based on the numerical analysis, simplified WFCS’s for implementation in the Row-A turbines are developed and tested against the more detailed optimized controller. The test predicts only a small reduction of performance enhancement of the simplified controller compared to the detailed controller, and on this basis it is decided to use the simplified controller for the full-scale turbine implementation. The test, toggling between base control and optimal control in 50-minute successive time slots, has been running since 09-05-2022 and is still ongoing. A huge amount of data is needed to obtain robust statistics for the comparison of measured and numerical data.
Nonlinear Dynamical Analysis of Composite Boring Bar with Nano-carbon Materials
Authors: Zhang Jinfeng , Jia Junlei , Feng Chao , Zhong Peisi 
Published: May 2023

Abstract
Preventing resonance in boring bar vibration is the key to achieve high quality and efficiency. In this paper, using the three-dimensional nonlinear dynamic model of boring process, the cutter bar is simplified as a rotating non planar bending axis, starting from the constitutive relationship and stress displacement relationship of composite materials. Based on Hamilton principle, the nonlinear motion differential equation of cutting process is established. The nonlinear partial differential equations of bending vibration are discretized by Galerkin method. Using the multi-scale method, the frequency response functions of the system in the primary resonance and super resonance are obtained. Using this model, the effects of the length diameter ratio of nano-carbon materials and the content of nano-carbon materials on the vibration frequency response of the boring bar are studied. The results show that the steady vibration amplitude of the cutter bar can be reduced by adding nano-carbon materials to the fiber reinforced polymer composite (FRP) beam.
Flap-lag flutter of high-speed rotating blade section of wind turbine
Authors: Liu Haixiu , Zhang Wenhe , Liu Tingrui 
Published: May 2023

Abstract
This study is to investigate the stall flutter of high-speed rotating blade section of small-scale blades subjected to combined flap-lag motion. The work is motivated by destructive flapwise vibrations of small-scale blades. The aeroelastic governing equations combine a spring-mass-damper equivalent of the structure and a nonlinear aerodynamic model suitable for pure pitching motion. The nonlinear resulting equations are solved by linearization and time-marching approach. The stall flutter stability characteristics are investigated, with flutter suppression discussed.
Study of the Ejection Process of Cold Ejection System with Flexible Cylinder by Corpuscular Method
Authors: Yang Baosheng , Su ZhengYu , Yang Lina , Jiang Yi , Zhao Zhen 
Published: May 2023

Abstract
Cold ejection is widely used in the realm of ejection, but conventional ejection systems can’t adapt to the modern war due to obvious infrared characteristics and high energy consumption, so new ejection system is desired. This work demonstrates a new way of flexible ejection, which is based on control method and corpuscular Method. Firstly, a finite element model of the flexible cylinder ejection system is established. Then, the corpuscular method is applied to study the influence of length and cross-section diameters of the cylinder on the dynamic of ejection process. It is found that the length of flexible cylinder will prolong the time of ejection from 0.72s to 1.01s with length increase from 7.2m to 10.4m. However, the diameter decreases the ejection time. Meanwhile, the velocity increases from 14.37m/s to 15.46m/s with cross-section diameter of cylinder increases from 0.60m to 0.75m. And the maximum overload is bigger 25.9 % than minimum.
Simulation of Flexible Dual-mode Surface Acoustic Wave Resonator for Strain Sensor Application
Authors: Huang Shitian , Luo Wenbo , Lv Lu , Yao Shuai , Wu Chuangui , Zhang Wanli 
Published: May 2023

Abstract
Based on the requirement of flexible electronic devices (FED)such as surface acoustic wave (SAW) sensors, finite element models for material analysis and SAW resonator design were established. Dual-mode of Rayleigh and Horizontal Shear mode on 0ºY cut LiNbO3 thin film was discovered. The influence of BCB thickness and PI substrate on resonant mode was analyzed. The flexible SAW resonator owned high sensitivity both in Rayleigh mode and Horizontal shear mode under tensile stress and compressive stress by simulation.
Dynamic Simulation and Research of Land-Based Missile Tilt Launch Platform
Authors: Wen Xianghua , Jiang Yi , Yan Song , Zhu Qizhang , Ren Ruoyu 
Published: May 2023

Abstract
In order to study the influence of the structural factors of the launch device on the missile tilt projectile dynamics, a dynamic model of the missile tilt launch platform was established based on the finite element method. The effects of shock absorber stiffness, angle between shock absorber and horizontal plane and tilt of the launch device were studied on the missile and launch platform’s ejection response characteristics. The research results show that the greater the rigidity of the shock absorber, the smaller the angle between the shock absorber and the horizontal plane, and the smaller the vibration amplitude of the initial disturbance of the missile and the launch cylinder; when the tilt angle of the launch device is within 6 °, the angle change has a smaller impact on the speed of the missile outlet, and there is a sufficient safety distance between the missile and the launch canister during the launch process. The larger the vibration amplitude of the initial disturbance and the launch tube. The research results can provide a theoretical reference for the design and optimization of the tilted launch platform.
Research on requirement fusion of imaging reconnaissance satellites
Authors: Zhao Yulong , Zhang Yuan , Xu Can , Wang Yan 
Published: May 2023

Abstract
Aiming at the problem of how to improve the requirement satisfaction of multi-point target imaging reconnaissance tasks and the utilization efficiency of satellite resources, a multi-point target imaging reconnaissance requirement fusion method based on genetic optimization is proposed in this paper. Firstly, the basic constraints that can be fused between multi-point targets are analysed, and on this basis, a point-target synthetic observation model is constructed. Secondly, considering the constraints of observation time window, observation angle and transition time between synthetic tasks, a genetic algorithm-based multi-point target requirements fusion method is designed. Finally, through the simulation analysis, it is concluded that with the continuous increase of user requirements, the fusion method based on genetic optimization can still achieve better task satisfaction to the user’s imaging requirements, which greatly improves the use efficiency of imaging satellites.
Combustion Surface Calculation Method of Solid Rocket Propellant Based on Parameterized Volume Boolean Operation
Authors: Sun Ruiyang , Jiang Yi 
Published: May 2023

Abstract
In order to solve the problem of long time consuming and low efficiency in solving the complex combustion surface of solid rocket propellant, a combustion surface calculation method based on parameterized volume Boolean operation was proposed. After the solid model of propellant was created by using 3D modeling software, the parameterized burning surface model was used to perform Boolean difference calculation between the obtained burning surface growth entity and the propellant entity. Through Sensitivity Analysis function, the variation range of parameterized value was set, so as to obtain the burning face value under different burning thickness. In this paper, star shaped charge column is selected to calculate the combustion surface, and the feasibility of the method is verified. This method provides a basis for subsequent combustion surface calculation.
A High Isolation Dual-band WiFi MIMO Antenna Design
Authors: Yuan Kang , Nie Qilei , Zhang Songtao , Peng Lihu , Wang Qinghai , Liu Geng 
Published: May 2023

Abstract
In this paper, a dual-band WiFi MIMO antenna with high isolation is designed. The antenna is F-Type structure, and the resonant points of high frequency and low frequency are mainly controlled by two branches of ‘F’. In order to improve the isolation between antennas, multiple symmetrically distributed slots are introduced on the ground, by adjusting the size and spacing of each group of slots, the effect of 2.4GHz & 5G dual-band decoupling is realized. Through HFSS simulation and optimization, antenna in frequency of 2.4-2.5GHz & 5.2-5.825GHz, S11 meet-10db bandwidth requirements, the isolation between the two ports is higher than 25dB, meet the design requirements.
A Game Coordination Optimization Algorithm
Authors: Zhu Yuyu , Wu Qing’e , Xiao Na , Wang Wenjing 
Published: May 2023

Abstract
In order to solve the problems of information flow and traffic jams, this paper proposes a game coordination optimization algorithm, and gives a coordination optimization model for the communication signal area. A game coordination strategy algorithm is studied using multi-agent technology. This model can make all local area networks and routing ports fully cooperate, so that the communication signals of a certain area can be coordinated and optimized. At the same time, the application of the game coordination optimization algorithm in power grid intelligent communication, control and resource optimization is given. By comparing the communication effect under different coordination probabilities, the simulation results show that the communication effect under high coordination probability has obvious advantages such as high fidelity, low distortion, fast communication speed, and small communication volume. The development of these studies can in turn accelerate the application of game and agent algorithms in various fields.
Application and Implementation of Artificial Intelligence Technology for Intelligent Vehicle
Authors: Guo Yong , Wu Shikai , Wang Yu , Wen ChongBin , Luo Le , Fu Qiang 
Published: May 2023

Abstract
With the development of artificial intelligence (AI) and the advancement of industrial technology, electric vehicles have become the main tools for people’s travel mobility. In order to cope with the faster rhythms of life and to meet people’s aspirations to live a better life, the integration of AI technology and automobiles is becoming closer and more popular. In this study, the transplantation of TensorFlow and Keras architecture on the embedded platform is implemented. An intelligent tracking car is designed and completed. It takes one i.MX RT1064 as the core processor, two electromagnetic rods as the tracking sensors, a steering gear and a motor as the motion control system, and has the application of neural network algorithm in the training and operation stages. The application of convolutional neural networks to the electromagnetic tracking of intelligent car is realized. Through the research of this smart car model, it helps to deeply understand the key technologies and automotive automation control systems of smart car manufacturing, and lay a solid foundation for designing practical smart cars in the future
Experimental and simulation research on the electrical characteristics of 1553B bus system
Authors: Feng Shuai , Wang Lei , Wang Yan , Hu Yusang , Cai Biao , Yu Dan 
Published: May 2023

Abstract
An experimental system of 1553B bus is build, and several key parameters of the system are measured. A simulation method for the electrical characteristics of 1553B system using Matlab/Simulink is proposed. The experimental results and the simulation results are compared, and the comparison shows the effectiveness and correctness of the simulation method. Then, the electrical characteristics of 1553B bus system with different structural configurations are simulated, and qualitative suggestions for the design of the 1553B bus system are given.
Mechanical and microstructure evaluation of novel hybrid TiB2/B4C aluminium metal matrix composite
Authors: Senthilnathan T , Balachandar K 
Published: May 2023

Abstract
In the current study, a novel approach that integrated in situ and ex situ reinforcement techniques was used to develop a hybrid AA7475 aluminium metal matrix composite (MMC). The primary objective of this study was to explore the viability of producing in situ TiB2 particles and adding ex situ B4C particles as reinforcements in the same melt of the aluminium alloy AA7475, with the intention of using these ceramic fillers to improve the mechanical properties of bare AA7475. For in situ particle synthesis, salts such as K2TiF6 and KBF4 were used and for ex situ, B4C particles are utilized. The aluminium MMC was prepared using stir casting method and characterized using ASTM standards. For comparison, composite with only in situ TiB2 particles and composite with only ex situ B4C particles were also fabricated. According to the results, the highest tensile strength of 156.57 MPa was achieved for the hybrid composite made using 5wt% of B4C and TiB2. Similarly, the highest hardness of 144.67 HV was observed for the same. However, the presence of both TiB2 and B4C improved the hardness together. The microstructure shows highly refined phases of the matrix and also the formation of precipitates and reinforcements clearly. The EDAX and XRD confirm the intermetallics formation and dispersion of particles within the matrix material. This aluminium composite with improved properties could be used in automotive, aircraft and in defense sectors where lightweight and high strength materials are required.