Article
Engineering, Marine
Jiahuan Lin, Huawei Duan, Baoming Xu, Yangwei Wang, Jun Zhang
Summary: This study proposes the use of an XAM system and WTSM method to redesign the blades of an offshore floating wind turbine, aiming to address the issue of the Froude-scaled model's inability to accurately reproduce the thrust performance of the reference wind turbine. The results show that the redesigned blades match well with the reference blades in terms of thrust performance at different pitch angles.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Thermodynamics
Yefeng Cai, Haisheng Zhao, Xin Li, Yuanchuan Liu
Summary: This paper proposes a reliable criterion based on the velocity field of FOWT to distinguish its operating states (VRS or PWS) and considers the aerodynamic characteristics and flow mechanism of the FOWT in detail.
Article
Green & Sustainable Science & Technology
Weiyuan Shi, Jin Jiang, Ke Sun, Quanyong Ju
Summary: The study focuses on the effects of pitch motion on the NREL 5MW wind turbine using Computational Fluid Dynamics (CFD) method. It investigates the aerodynamic characteristics and power output changes of the blades under different conditions. Results show a significant impact of pitch motion on the performance of the wind turbine, highlighting the need for comprehensive consideration.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2021)
Article
Green & Sustainable Science & Technology
Yang Zhou, Qing Xiao, Yuanchuan Liu, Atilla Incecik, Christophe Peyrard, Decheng Wan, Guang Pan, Sunwei Li
Summary: The present study investigates the effect of turbulent wind and shear wind on the structure of a floating offshore wind turbine using a high-fidelity computational fluid dynamics method. The study demonstrates that turbulent wind causes fluctuations in rotor thrust and power outputs, and results in faster wake diffusion compared to time-independent inflow wind. Wind shear exacerbates the decrease in local minimum thrust/power. However, under the current wind inflow conditions, neither turbulent wind nor wind shear significantly affect the inline surge force, dynamic motion, and mooring tension of the floater.
Article
Green & Sustainable Science & Technology
Ziwen Chen, Xiaodong Wang, Yize Guo, Shun Kang
Summary: This study investigates the aerodynamic characteristics of floating offshore wind turbines under different motions using computational fluid dynamics simulations. It is found that increasing amplitude and frequency can aggravate the fluctuation of the overall aerodynamic performance of wind turbines. Additionally, complex platform motions adversely affect the power generation of floating offshore wind turbines.
Article
Engineering, Mechanical
Tao Chen, Xiao Jiang, Haipeng Wang, Qian Li, Mingzhou Li, Zhou Wu
Summary: The study found that the installation angles of the leading-edge slat have a significant impact on the lift coefficient and torque, improving the performance of wind turbine blades.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE
(2021)
Article
Engineering, Marine
Binrong Wen, Zehao Liang, Hang Zhang, Ke Fan, Ye Wang, Da Li, Xinliang Tian, Zhike Peng
Summary: This paper presents a Multi-drive Aerodynamic Loading Simulator (MALS) designed for model tests of Floating Wind Turbines (FWTs). The MALS, equipped with high-performance UAV propellers, can generate desired aerodynamic thrusts accurately. Extensive performance evaluation tests demonstrate that the MALS meets the requirements of practical wind turbines. Furthermore, a hybrid model test system based on the MALS is constructed for studying the dynamic characteristics of FWT systems.
Article
Thermodynamics
Baifeng Ji, Kuanwei Zhong, Qian Xiong, Penghui Qiu, Xu Zhang, Liang Wang
Summary: In this study, different turbulence models were used to numerically simulate the aerodynamic characteristics of wind turbines, and the results were compared with experimental data. The findings suggest that the choice of turbulence model and inlet wind speed can affect the accuracy of predicting the aerodynamic characteristics of the blades.
Article
Energy & Fuels
Paulo Gonzaga, Henrik Toft, Keith Worden, Nikolaos Dervilis, Lars Bernhammer, Nevena Stevanovic, Alejandro Gonzales
Summary: This paper focuses on modeling the effect of structural and aerodynamic uncertainties in wind turbine blades. It uses wind tunnel measurements and Monte Carlo simulations to define and propagate these uncertainties. The aim is to provide a framework for dealing with uncertainties in wind turbine blade design and understanding their effects on turbine behavior.
Article
Engineering, Civil
Hongyu Wang, Bin Chen
Summary: Wind turbine blades are highly susceptible to leading edge erosion, which significantly reduces their aerodynamic performance and power generation efficiency. Current acoustic-based erosion detection methods face major challenges. In this paper, the computational fluid dynamics method is used to investigate the aerodynamic noise mechanism of eroded blades. The Zonal Detached Delay Eddy Simulation turbulence model is applied to obtain the three-dimensional turbulent flow field. Far-field aerodynamic noise analysis is then performed using the Ffowcs Williams and Hawkings approach. Simulations are conducted for erosion conditions of a 5-MW wind turbine determined by the length and depth at the leading edge. Results show that erosion causes unsteady pressure pulsations near the leading edge, a decrease in surface pressure difference in the tip area, an increase in airflow separation region, and a forward movement of the separation point. Additionally, the eroded blade exhibits higher acoustic levels compared to the normal blade. The noise directivity analysis reveals asymmetry of the noise pattern in the upwind and downwind directions due to erosion.
JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS
(2023)
Article
Engineering, Civil
Wonsuk Han, Homin Kim, Eunkuk Son, Soogab Lee
Summary: This study investigates the impact of wake steering on wind turbines using the unsteady vortex lattice method (UVLM) and the curled wake model. The results show that the counter-rotating vortices significantly affect the aerodynamics of wind turbines, including the effective angle of attack and wake deflection.
JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS
(2023)
Article
Mechanics
Guanbin Sheen, Mingwei Yin, Xianyu Wang, Hexi Baoyin
Summary: This article uses the unsteady vortex lattice method to validate and analyze the aerodynamic characteristics of the intermeshing rotor in hover. The results show the existence of low-order frequency harmonic components and phase lag phenomenon in dual rotor loads. Additionally, the left/right rotor loads have harmonic components of 1, 2, and 3 k omega.
Article
Green & Sustainable Science & Technology
Hui Tong, Ying Wang
Summary: This study conducted experiments on a wind tunnel test platform to simulate the operation of blades on a vertical axis wind turbine (VAWT), concluding that the maximum lift force of a blade with an amplitude of 0.06c is nearly 60% higher than that of a rigid blade. Additionally, changing parameters such as the initial angle of attack resulted in different aerodynamic characteristic curves for the blade.
Article
Energy & Fuels
Ivan Castro-Fernandez, Ricardo Borobia-Moreno, Rauno Cavallaro, Gonzalo Sanchez-Arriaga
Summary: The study investigated the validity of using a low-computational-cost model for the aerodynamic characterization of Airborne Wind Energy Systems. The comparison between experimental and theoretical aerodynamic coefficients showed good agreement in lift and lateral force coefficients, but discrepancies in drag coefficients. Uncertainties in experimental data made the comparison of aerodynamic torque coefficients more challenging.
Article
Engineering, Aerospace
Wei Gao, Yishu Liu, Qifu Li, Bei Lu
Summary: A rapid modeling approach, based on the unsteady vortex lattice method and potential flow theory, is developed for aerodynamic computation of multi-lifting surfaces. The approach allows for quick integration and meshing of multiple lifting surfaces with different geometric parameters and grid divisions. Physical influence between lifting surfaces and wake-surface interaction are modeled, and different built-in vortex core models are used. Trajectory data is used to replace pre-calculated downwash superposition for boundary condition integration, and instantaneous boundary condition is generated directly from the kinematic states and mesh messages of the model concerned. Considering the direct coupling effect between aerodynamics and rigid body dynamics, a function for free flight is built for medium-fidelity dynamic simulations and aerodynamic data identifications. The proposed modeling and simulation process is highly efficient and can be easily applied to models with any number of lifting surfaces and arbitrary motion modes.
Article
Green & Sustainable Science & Technology
Cameron Bracken, Nathalie Voisin, Casey D. Burleyson, Allison M. Campbell, Z. Jason Hou, Daniel Broman
Summary: This study presents a methodology and dataset for examining compound wind and solar energy droughts, as well as the first standardized benchmark of energy droughts across the Continental United States (CONUS) for a 2020 infrastructure. The results show that compound wind and solar droughts have distinct spatial and temporal patterns across the CONUS, and the characteristics of energy droughts are regional. The study also finds that compound high load events occur more often during compound wind and solar droughts than expected.
Article
Green & Sustainable Science & Technology
Ning Zhang, Yanghao Yu, Jiawei Wu, Ershun Du, Shuming Zhang, Jinyu Xiao
Summary: This paper provides insights into the optimal configuration of CSP plants with different penetrations of wind power by proposing an unconstrained optimization model. The results suggest that large solar multiples and TES are preferred in order to maximize profit, especially when combined with high penetrations of wind and photovoltaic plants. Additionally, the study demonstrates the economy and feasibility of installing electric heaters (EH) in CSP plants, which show a linear correlation with the penetration of variable energy resources.
Article
Green & Sustainable Science & Technology
M. Szubel, K. Papis-Fraczek, S. Podlasek
Article
Green & Sustainable Science & Technology
J. Silva, J. C. Goncalves, C. Rocha, J. Vilaca, L. M. Madeira
Summary: This study investigated the methanation of CO2 in biogas and compared two different methanation reactors. The results showed that the cooled reactor without CO2 separation achieved a CO2 conversion rate of 91.8%, while the adiabatic reactors achieved conversion rates of 59.6% and 67.2%, resulting in an overall conversion rate of 93.0%. Economic analysis revealed negative net present worth values, indicating the need for government monetary incentives.
Article
Green & Sustainable Science & Technology
Yang Liu, Yonglan Xi, Xiaomei Ye, Yingpeng Zhang, Chengcheng Wang, Zhaoyan Jia, Chunhui Cao, Ting Han, Jing Du, Xiangping Kong, Zhongbing Chen
Summary: This study investigated the effect of using nanofiber membrane composites containing Prussian blue-like compound nanoparticles (PNPs) to relieve ammonia nitrogen inhibition of rural organic household waste during high-solid anaerobic digestion and increase methane production. The results showed that adding NMCs with 15% PNPs can lower the concentrations of volatile fatty acids and ammonia nitrogen, and increase methane yield.
Article
Green & Sustainable Science & Technology
Zhong Ge, Xiaodong Wang, Jian Li, Jian Xu, Jianbin Xie, Zhiyong Xie, Ruiqu Ma
Summary: This study evaluates the thermodynamic, exergy, and economic performance of a double-stage organic flash cycle (DOFC) using ten eco-friendly hydrofluoroolefins. The influences of key parameters on performance are analyzed, and the advantages of DOFC over single-stage type are quantified.
Article
Green & Sustainable Science & Technology
Nicolas Kirchner-Bossi, Fernando Porte-Agel
Summary: This study investigates the optimization of power density in wind farms and its sensitivity to the available area size. A novel genetic algorithm (PDGA) is introduced to optimize power density and turbine layout. The results show that the PDGA-driven solutions significantly reduce the levelized cost of energy (LCOE) compared to the default layout, and exhibit a convex relationship between area and LCOE or power density.
Article
Green & Sustainable Science & Technology
Chunxiao Zhang, Dongdong Li, Lin Wang, Qingpo Yang, Yutao Guo, Wei Zhang, Chao Shen, Jihong Pu
Summary: In this study, a novel reversible liquid-filled energy-saving window that effectively regulates indoor solar radiation heat gain is proposed. Experimental results show that this window can effectively reduce indoor temperature during both summer and winter seasons, while having minimal impact on indoor illuminance.
Article
Green & Sustainable Science & Technology
Alessandro L. Aguiar, Martinho Marta-Almeida, Mauro Cirano, Janini Pereira, Leticia Cotrim da Cunha
Summary: This study analyzed the Brazilian Equatorial Shelf using a high-resolution ocean model and found significant tidal variations in the area. Several hypothetical barrages were proposed with higher annual power generation than existing barrages. The study also evaluated the installation effort of these barrages.
Article
Green & Sustainable Science & Technology
Francesco Superchi, Nathan Giovannini, Antonis Moustakis, George Pechlivanoglou, Alessandro Bianchini
Summary: This study focuses on the optimization of a hybrid power station on the Tilos island in Greece, aiming to increase energy export and revenue by optimizing energy fluxes. Different scenarios are proposed to examine the impact of different agreements with the grid operator on the optimal solution.
Article
Green & Sustainable Science & Technology
Peimaneh Shirazi, Amirmohammad Behzadi, Pouria Ahmadi, Sasan Sadrizadeh
Summary: This research presents two novel energy production/storage/usage systems to reduce energy consumption and environmental effects in buildings. A biomass-fired model and a solar-driven system integrated with photovoltaic thermal (PVT) panels and a heat pump were designed and assessed. The results indicate that the solar-based system has an acceptable energy cost and the PVT-based system with a heat pump is environmentally superior. The biomass-fired system shows excellent efficiency.
Article
Green & Sustainable Science & Technology
Zihao Qi, Yingling Cai, Yunxiang Cui
Summary: This study aims to investigate the operational characteristics of the solar-ground source heat pump system (SGSHPS) in Shanghai under different operation modes. It concludes that tandem operation mode 1 is the optimal mode for winter operation in terms of energy efficiency.
Article
Green & Sustainable Science & Technology
L. Bartolucci, S. Cordiner, A. Di Carlo, A. Gallifuoco, P. Mele, V. Mulone
Summary: Spent coffee grounds are a valuable biogenic waste that can be used as a source of biofuels and valuable chemicals through pyrolysis and solvent extraction processes. The study found that heavy organic bio-oil derived from coffee grounds can be used as a carbon-rich biofuel, while solvent extraction can extract xantines and p-benzoquinone, which are important chemicals for various industries. The results highlight the promising potential of solvent extraction in improving the economic viability of coffee grounds pyrolysis-based biorefineries.
Article
Green & Sustainable Science & Technology
Luiza de Queiroz Correa, Diego Bagnis, Pedro Rabelo Melo Franco, Esly Ferreira da Costa Junior, Andrea Oliveira Souza da Costa
Summary: Building-integrated photovoltaics, especially organic solar technology, are important for reducing greenhouse gas emissions in the building sector. This study analyzed the performance of organic panels laminated in glass in a vertical installation in Latin America. Results showed that glass lamination and vertical orientation preserved the panels' performance and led to higher energy generation in winter.
Article
Green & Sustainable Science & Technology
Zhipei Hu, Shuo Jiang, Zhigao Sun, Jun Li
Summary: This study proposes innovative fin arrangements to enhance the thermal performance of latent heat storage units. Through optimization of fin distribution and prediction of transient melting behaviors, it is found that fin structures significantly influence heat transfer characteristics and melting behaviors.