bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of the capacity factor of stationary wind turbines and weather-routed energy ships in the far-offshore
Authors: Jamil Roshamida ABD , Chaigneau Alisée , Gilloteaux Jean-Christophe , Lelong Philippe , Babarit AuréLien 
Published: October 2019

Abstract
Offshore wind energy technology has developed rapidly over the last decade. It is expected to significantly contribute to the further increase of renewable energy in the global energy production in the future. However, even with floating wind turbines, only a fraction of the global offshore wind energy potential can be harvested because grid-connection, moorings, installation and maintenance costs increase tremendously as the distance to shore and the water depth increase. Thus, new technologies enabling harvesting the far offshore wind energy resource are required. To tackle this challenge, mobile energy ship concepts have been proposed. In those concepts, electricity is produced by a water turbine attached underneath the hull of a ship propelled by the wind using sails. It includes an on-board energy storage system since energy ships are not grid-connected. Thus, the ships route schedules could be dynamically optimized taking into account weather forecast in order to maximize their capacity factors (CF). The aim of this study is to investigate how high the capacity factors of energy ships could be when using weather-routing and compare them to that of stationary wind turbines that would be deployed in the same areas. To that end, a modified version of the weather-routing software QtVlm was used. Velocity and power production polar plots of an energy ship that was designed at LHEEA were used as input to QtVlm. Results show that capacity factors over 80% can be achieved with energy ships and stationary offshore wind turbines deployed in the North Atlantic Ocean.
Processing of sonic anemometer measurements for offshore wind turbine applications
Authors: Nybø A , Nielsen F G , Reuder J 
Published: October 2019

Abstract
Quality assured measurements from offshore masts may provide valuable information of the characteristics of the offshore wind field, which is of high relevance for simulations of offshore wind turbines’ dynamic response. In order to obtain these high quality data sets, a processing procedure tailored to offshore wind turbine applications must be followed. In this study, existing quality control routines applied in literature are evaluated, and a complete procedure is developed for sonic anemometer measurements. This processing procedure is applied to measurements at three heights from 16 months of measurements at FINO1. The processing procedure results in a data set of more than 6 000 30-minute periods of high quality time series showing a large variety in terms of wind speed and turbulence intensity. Together with an assessment of the stationarity, this processed data set is ready for use in offshore wind turbine research.
Experimental Investigation of a Downwind Coned Wind Turbine Rotor under Yawed Conditions: Preliminary Results
Authors: Schulz C W , Wieczorek K , Netzband S , Abdel-Maksoud M 
Published: October 2019

Abstract
The growing number of Floating Offshore Wind Turbine (FOWT) concepts that utilize a single point mooring and therefore rely on the self-alignment capabilities of the wind turbine (e.g. SCD nezzy or SelfAligner by CRUSE Offshore) demands an extension of the simulation methods used for their development. A crucial issue for these concepts is the accurate prediction of forces and moments, which contribute to the self-alignment. In contrast to the well-studied behaviour of torque and thrust, yaw moment and lateral forces on a rotor under yawed conditions have not been in focus of previous experimental tests for the validation of aerodynamic simulation tools. In the present work, a model turbine equipped with a 6-axis force/moment sensor to capture the complete load on the rotor is presented. A detailed study of the two-bladed model turbine’s aerodynamic behaviour under yawed conditions was carried out within a range of yaw angles between -55 to + 55° with steps of 1 – 2.5°.
Verification of Floating Offshore Wind Linearization Functionality in OpenFAST
Authors: Johnson N , Jonkman J , Wright A , Hayman G , Robertson A 
Published: October 2019

Abstract
The wind engineering community relies on multiphysics engineering software to run nonlinear time-domain simulations, e.g., for design standards-based loads analysis. Although most physics involved in wind energy are nonlinear, linearization of the underlying nonlinear system equations is often advantageous to understand the system properties and exploit well-established methods and tools for analyzing linear systems. Previous work in this area has focused on the development of the new linearization functionality of the open-source engineering tool OpenFAST for floating offshore wind turbines, as well as the concepts and mathematical background needed to understand and apply it correctly. This paper focuses on the verification of this new linearization functionality, which is carried out by comparing results to previous stable versions of FAST. A nonlinear time-domain simulation for a floating offshore platform is also compared to the time-domain response of the linearized state-space model. The linearized results show good alignment between OpenFAST and previous versions of FAST, as well as with the time-domain simulations, thereby showing the accuracy of the new features in OpenFAST.
How does risk aversion shape overplanting in the design of offshore wind farms?
Authors: Mora Esteve Borràs , Spelling James , van der Weijde Adriaan H. 
Published: October 2019

Abstract
Offshore wind farms are subjected to a maximum export capacity set in their connection agreement with the Transmission System Operator (TSO). Generators can export up to their contracted maximum export capacity, with any additional generation curtailed by the TSO. However, given the fact that the majority of the time offshore wind farms are not generating at full power, overplanting wind farms by installing a higher wind farm capacity compared to the fixed electrical infrastructure can result in better overall economics despite power output being curtailed at generations’ peaks. The objective of this paper is to provide a framework to assess overplanting in the design of offshore wind farms when the underlying variables, such as wind speed and availability rates among others, are uncertain. The paper integrates site characteristics, technology specificities and financing constraints grounded in the mathematical framework of uncertainty quantification at the heart of the decision-making process. Generally speaking, the role of determining the optimal amount of overplanting comes down to the risk appetite of the developer, which in this paper is represented by a linear combination of the risk aversion and risk neutrality setting. A case study for a commercial offshore wind farm shows a 2% optimal overplanting for a Monte Carlo simulation, whereas this is found at 4% for a double Monte Carlo loop simulation regardless of the risk appetite considered. Furthermore, overplanting the farm by any value from 2% to 8% gives a better result than with no overplanting for a risk neutral setting. This paper will be of interest to developers, policy-makers and regulatory bodies confronted with uncertainty in overplanting the design of offshore wind farms.
Winding Reinforced UHPC Sandwich Structures for Lightweight Jackets for Offshore Megastructures
Authors: Markowski J , Lohaus L 
Published: October 2019

Abstract
The paper presents a new type of cross-section for truss elements in an offshore construction’s sub structure framework. By combining modern materials, such as ultra-high performance concrete (UHPC) and carbon fibre reinforced polymers in a hollow section, significant weight savings compared to conventional steel structures can be achieved. An extensive experimental programme has been carried out in order to describe the construction’s load-bearing behaviour. The article presents an overview of the development process of the design, the methodological implementation of the experimental investigations and the results.
Virtual synchronous machine control for wind turbines: a review
Authors: Lu L , Cutululis N A 
Published: October 2019

Abstract
Virtual synchronous machine (VSM) control has been put up and developing for the past ten years, but not much work has been done specially focusing on its application on wind turbines (WTs). This paper gives a thorough review of the work that has been done until now about application of VSM control on WTs. Aspects on control schemes, energy storage (ES), frequency and voltage control capabilities, different grid conditions etc. are summarized separately. Further research work in this field is emphasized.
Numerical prediction of hydrodynamic coefficients for a semi-sub platform by using large eddy simulation with volume of fluid method and Richardson extrapolation
Authors: Pan Jia , Ishihara Takeshi 
Published: October 2019

Abstract
Hydrodynamic coefficients for predicting hydrodynamic loading is significant for the design of offshore wind turbine floaters. In this paper, hydrodynamic coefficients for a semi-submersible floating offshore wind turbine are investigated experimentally and numerically. In the water tank test, added mass and drag coefficients of the semi-submersible model are identified by the forced oscillation tests. In numerical simulation, large eddy simulation (LES) with volume of fluid method (VOF) is adopted to predict added mass and drag coefficients. Firstly, numerical errors in the predicted hydrodynamic coefficients are systematically studied, and Richardson extrapolation is employed to obtain the grid independent solution. The predicted added mass and drag coefficients varying with KC number are then validated by the water tank tests and the mechanism of the hydrodynamic force are clarified by vortex shedding patterns. The hydrodynamic coefficients for each element are also investigated. Finally, effect of free surface on the hydrodynamic forces is discussed and the predicted added mass and drag coefficients are compared with those obtained from the water tank tests.
Implementation of potential flow hydrodynamics to time-domain analysis of flexible platforms of floating offshore wind turbines
Authors: Oh Sho , Ishii Kimiko , Iijima Kazuhiro , Suzuki Hideyuki 
Published: October 2019

Abstract
In the design of supporting platforms of floating offshore wind turbines, global response analysis is essential to predict the response under various loads from wave, wind, moorings and the wind turbines. However, the literature of the global analysis of floating offshore wind turbines combining flexible modelling of the supporting platform and the potential flow theory for hydrodynamic evaluation is limited. In this study, the framework implementing the potential flow hydrodynamics to the time-domain analysis of the three-dimensional frame model was developed using modal decomposition for the hydrodynamic evaluations. The method utilized the assumption that the number of modes can be limited to those with larger contributions, which can lead to the reduction of the calculation cost. A spar-type floating offshore wind turbine was modelled to verify the implementation of the developed formulations. Results showed that the implemented method is effective in predicting the dynamic motion and deformation of floating offshore wind turbines under combined wind and wave loads. For the cases of the irregular waves, the results obtained with potential flow hydrodynamics showed smaller responses than the results from the Morison’s equation in the natural frequencies of rigid body motion, which might be attributed to the steady and low frequency external forces introduced in the Morison’s equation by considering the instantaneous position of the floater.
Spatial met-ocean data analysis for the North Sea using copulas: application in lumping of offshore wind turbine fatigue load cases
Authors: Koochekali Alahyar , Muskulus Michael 
Published: October 2019

Abstract
Knowledge about stochastic environmental loads and the response of the substructure are essential in fatigue damage calculations for offshore wind turbines. Site-specific and high-quality met-ocean data that contains joint measurements of wind and waves however, are not always available. An approach based on copulas was used to generate lumped joint met-ocean data in a location where only marginals (i.e., individual, univariate probability distributions) are known. Empirical copulas were calculated for different stations in the North Sea for pairs of wind speed and wave height variables. These copulas are then combined with marginals from another station to generate lumped data. The generated data is compared with the known lumped joint data, and the difference of two methods is measured. The lumped values are used to estimate fatigue damage based on simple formulas. The results show that the joint behaviour of wind speed and wave height follows a similar pattern around the North Sea. In addition, the mean difference of generated lumped wind speeds based on this technique from lumped wind speeds based on real measurements is less than 5%. The mean difference of the fatigue damage caused by the generated lumped wind speeds relative to lumped wind speeds based on real measurements is less than 5% at two locations, and less than 15% in another location. This suggests that the approach is promising for estimating joint met-ocean data at new locations in the North Sea where only marginals are available, which is of major interest for wind farm planning and design.
Tribology Effect of Copper Based Composites for High-Speed Train Braking Application
Authors: Han Xiaoming , Yang Junying , Fu Rong , Su Linlin , Gao Fei 
Published: October 2019

Abstract
This paper disclosed the effect of third body on tribological performance of friction pair of copper-matrix materials and H13 steel using a fixed speed test from 3.14 m/s to 31.4 m/s at 0.5MPa. Results showed that the third body increase improved and stabilized friction coefficient. When the third body decreased, the friction coefficient decreased accordingly, especially at lower speed. This was because the particle third body of low-speed was weakly bound to the matrix, so the number of particles was easy to decrease.
Mechanical Properties and Strength Prediction of Ti Microalloyed Low Carbon Steel with Different Ti Content
Authors: Ren Jiakuan , Liu Zhenyu 
Published: October 2019

Abstract
The effects of Ti on microstructures, recrystallization and mechanical properties of microalloyed low carbon steels were studied. Hall-Petch relationship and Ashby-Orowan equation were applied to analyse the reason for the variation of strength. The results show that the recrystallization activation energy increases parabolically as the Ti content increases. Besides, the yield strength, tensile strength and the yield ratio increase in varying degrees with the increasing of Ti content, while the elongation decreases. The fine grain strengthening makes the greatest contribution to the strength, and the precipitation strengthening of TiC particles is the main reason why the strength of test steel increases significantly when the Ti content exceeds 0.042%. In addition, the strength prediction model was established for Ti microalloyed low carbon steel. The relative error of predicted yield strength and tensile strength of Q345B steel are within ± 8% and ± 7% respectively.
Simulation Research on Vibration Cutting Mechanism of Metal Matrix Composites
Authors: Yang Liang , Xu Chunguang , Fu Bohua , Zhang Mingzhao 
Published: October 2019

Abstract
Particle-reinforced metal composite materials have been widely used in the industry due to their excellent abrasion resistance and high strength, but they are typical hard-to-machine materials. A finite element model of the material matrix and enhanced particles have been established by the parametric modeling in this paper. Different from the previous development process, the particle is randomly distributed in this study, so the particle distribution has been better simulated than ever. The study shows that vibration-cutting particle-reinforced composites have reduced the phenomenon of particle suspension on the machined surface compared to conventional cutting, and the high-elastic-modulus reinforcing particles have been subjected to high stress, and the matrix between the particles have acted as a stress-transmitting “channel”. When the particle’s diameter is 20μm and the volume fraction is 30%, there is a stress transmitting channel in a certain range away from the tool tip. When the cutter contacts the particles, the vibration cutting will cause the initial crack near the particle, which cut off part of the stress transmitting channels, make the stress concentrated on the tool tip and lead to the material easier to remove.
Analysis of Sulfide Morphology in Non-quenched and Tempered Steel
Authors: Zhao Menghao , Ai Kenan , Li Zhiwei , Zhang Dong , Shen Ping , Fu Jianxun 
Published: October 2019

Abstract
Non-tempered steel without quenching and tempering heat treatment, saving energy and protecting the environment. Sulfide form is an important indicator of its production level. To explore the gap between the levels of sulphide control in 3 steel mills, metallographic microscope, scanning electron microscope and small sample electrolysis technology were used to analysis and comparison of sulfides in non-quenched and tempered steel produced by plant A (Germany), plant B (domestic), and plant C (domestic). The ratings of Class A inclusions in the three plants are: plant A is coarse grade 2.5 and fine grade 2.0, the sulfide are short rod shape; plant B is coarse grade 2.5 and fine grade 2.5, most of the inclusions are short rods, a few are long strips, and there are inclusions with MnTe; plant C is coarse grade 2.5 and fine grade 3.0, inclusions are generally long strips. The non-quenched and tempered steel inclusions produced by plant A are evenly distributed, and the sulfide form is well controlled.
Development of CPP Based Low Temperature Heat Sealing Film Material
Authors: Xiong Ligui , Tu Zhigang , Zhang Shangxian , Zhang Liqiong 
Published: October 2019

Abstract
The casting polypropylene (cpp) heat sealing film was prepared by adding the homemade smooth masterbatch, in the storage period of 30 days measured the surface tension is greater than 38 mN/m, the non-corona surface friction coefficient between 0.1 ∼ 0.2, corona surface is 0.5, the longitudinal tensile strength reached 60 MPa, transverse tensile strength reached 27 MPa, the films have high surface tension, low friction coefficient, high mechanical strength properties. Measured at the same time its initial heat sealing temperature, heat sealing strength and optical properties are better than the national standard, to maintain film comprehensive properties are stable during the storage period.
Preparation of Coral-like SnO2 Hierarchical Nanostructures and Its Application in Ethanol Gas-sensing Performance
Authors: Yan Shaohui , Zhang Jie , Huang Yibo , Lu Yan 
Published: October 2019

Abstract
Coral-like SnO2 hierarchical nanostructures were successfully fabricated by a simple hydrothermal route. By means of a comprehensive analysis of microstructures and morphologies of the hierarchical SnO2, we found that the coral-like nanostructures were comprised of irregular nanorods and nanosheets. Considering the essential advantages of hierarchical architectures, its gas sensitivity and the formation mechanism have been further explored. The sensor response to 100 ppm ethanol is about 25 at the optimum working temperature of 240 °C, and the response and recovery time are about 17 s and 7 s, respectively. Based on the experimental results, a possible morphology-dependent sensing mechanism are speculated.
Effects of Application of BB Fertilizer on the Yield, Quality and Economic Benefits of Citrus
Authors: Huang Dongfeng , Pan Zhucai , Qiu Xiaoxuan 
Published: October 2019

Abstract
The effects of four different fertilization treatments [i.e., Conventional fertilization, 45% imported compound fertilizer, Sacofu compound fertilizer (N-P2O5-K2O=20-10-10), BB fertilizer for citrus (N-P2O5-K2O=19-8-13)]on yield, quality and economic benefit of Newhall navel orange were studied through three-year field plot experiment. The results showed that compared with conventional fertilization treatment, the application of Citrus BB fertilizer could not only increase the yield of Newhall navel orange by 13.65%, increase the soluble solids (TSS) content by 51.50%, soluble sugar (WSS) content by 56.64%, vitamin C (Vc) content by 8.87%, reducing the titratable acid (TA) content by 22.83%, increase the solid-acid ratio of navel orange fruit by 96.31%, sugar-acid ratio by 102.97%, but also enhance the economic benefit by 15496 yuan/hm2. Therefore, the special BB fertilizer for citrus is suitable for further popularization and application in citrus orchards on hilly red soil hills in Fujian Province and even in southern China, where the climate and soil conditions are similar to those in Fujian Province.
Taste Correction and Safety Evaluation of Rhodiola Extraction
Authors: Zhao Shouqing , Wang Shanshan , Xue Changsong , Xia Guangqing 
Published: October 2019

Abstract

Objective To explore tannins removal of Rhodiola extraction and evaluate its safety. Method: Content of Tannins was treated with cheese, tannins removal was used by chitosan embedding, safety evaluation was tested by acute toxicity. The pharmacodynamics were detected by in vivo and in vitro antioxidant methods. Results: 20g/L Rhodiola extraction added 1g chitosan under 50°C embedding 2h, tannis was removed effectively and taste improved greatly. The results of acute toxicity tests in mice showed that the daily dose of 29.73 g was safe on the basis of 70kg adult weight. Antioxidant activity in vitro was evaluated by DPPH, super-oxide anion and hydroxyl radical scavenging assays showed at concentration of 0.1% indicated better results, while results in vivo showed at concentration of 1.2% decreased p53, p21 gene expression. Conclusion: A reasonable process for removing tannins from were determined Rhodiola extraction and taste of Rhodiola extraction is safe under the removal extraction technique. Results of antioxidant proved that Rhodiola extraction is effective.
Modeling Design of Instrument Panel
Authors: Chen Wei 
Published: October 2019

Abstract
The basic requirements of instrumentation modeling, composition and layout, representation of functional areas, color, text, graphic symbols and signage, materials and coloring technology are discussed. The panel modelling should meet the following basic requirements, that is, the needs of product function, the needs of product uses, quick recognition, adaptability, artistry, and easy installation, adjustment and maintenance; The composition and layout of the panel are mainly panel composition of characteristic rectangular and panel composition of non-characteristic rectangular; The functional area of the panel can be divided into six types: wireframes, brackets, color blocks, spaces, segmentation lines and volume and surface; The color of the panel should consider its main color and matching color; Words, graphic symbols and signs on the panel, as well as the materials and coloring technology used in the panel are also factors that must be considered. The selection of materials is very important.