Ajay Veludurthi¹, Venkateshwarlu Bolleddu^2,*

Energy Engineering, Vol.117, No.2, pp. 49-61, 2020, DOI:10.32604/EE.2020.010666 - 23 April 2020

Abstract This work focused on modal and harmonic analysis of small wind turbine blades taken from the NACA 63415 series. The sandwich structure type composite blade is fabricated from GFRP and epoxy with Uni-vinyl hard foams of different alignments as stiffeners. In this work, the modal and harmonic analysis of different varieties of blades like solid, hallow and rectangular alignment blades is carried out by the finite element method using ANSYS 18.1 software. From Finite Element Analysis, the natural frequencies, amplitudes and mode shapes are obtained. Based on the working principle of wind turbine blades, the More >

Shuzhuang Zhang¹, Hao Luo¹, Zhigang Wu¹, Yanbin Sun^{2, *}, Yuhang Wang², Tingting Yuan³

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 213-222, 2020, DOI:10.32604/cmc.2020.07496 - 30 March 2020

Abstract With the rapid increase of link speed and network throughput in recent years, much more attention has been paid to the work of obtaining statistics over speed traffic streams. It is a challenging problem to identify heavy hitters in high-speed and dynamically changing data streams with less memory and computational overhead with high measurement accuracy. In this paper, we combine Bloom Filter with exponential histogram to query streams in the sliding window so as to identify heavy hitters. This method is called EBF sketches. Our sketch structure allows for effective summarization of streams over time-based More >

Haytham Ayoub, Ehab Hussein Bani-Hani^*

Energy Engineering, Vol.117, No.1, pp. 41-47, 2020, DOI:10.32604/EE.2020.010412 - 28 February 2020

Abstract Offshore wind turbine is analyzed theoretically and experimentally for improving wind energy harvesting. The energy produced is calculated at different wind speeds. The wind speed curve is generated by measuring the wind speed on daily base for one year. Curves that show the power extraction for experimental study and from the theoretical calculations are generated. The energy production investigation is expanded over a period of 15 years after comparing the annual energy production in theory and practice. The study shows the cost of electricity over the same time period assuming different interest rates. Three time… More >

Bingji Lan¹, Kanghao Yan^{1, *}

CMC-Computers, Materials & Continua, Vol.62, No.3, pp. 1303-1315, 2020, DOI:10.32604/cmc.2020.06584

Abstract In order to study the wind-induced vibration control effect of the viscous damper on the large-scale substation frame, this paper takes the large-scale 1000 kV substation frame of western Inner Mongolia as an example. The time-history sample of pulsating wind load is simulated by harmonic superposition method based on Matlab software. 6 kinds of viscous damper arrangement schemes have been designed, and SAP2000 finite element software is used for fine modeling and input wind speed time history load for nonlinear time history analysis. The displacement and acceleration of a typical node are the indicators of… More >

Yadong Zhang^{1, *}, Jiye Zhang²

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 105-120, 2020, DOI:10.32604/fdmp.2020.07959 - 01 February 2020

Abstract The object of research of this paper is the DSA380 high-speed pantograph. The near-field unsteady flow around the pantograph was investigated using large eddy simulation (LES) while the far-field aerodynamic noise was analysed in the frame of the Ffowcs Williams-Hawkings (FW-H) acoustic analogy. According to the results, the contact strip, base frame and knuckle are the main aerodynamic noise sources, with vortex shedding, flow separation and recombination around the pantograph being related key physical factors. The aerodynamic noise radiates outwards in the form of spherical waves when the distance of the noise receiving point is… More >

Haiqing Li¹, Mengge Yu^{1, *}, Qian Zhang¹, Heng Wen¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 77-90, 2020, DOI:10.32604/fdmp.2020.07797 - 01 February 2020

Abstract The performances of high-speed trains in the presence of coupling effects with crosswind and rain have attracted great attention in recent years. The objective of the present paper was to investigate the aerodynamic characteristics of a high-speed train under such conditions in the framework of an Eulerian-Lagrangian approach. An aerodynamic model of a high-speed train was first set up, and the side force coefficient obtained from numerical simulation was compared with that provided by wind tunnel experiments to verify the accuracy of the approach. Then, the effects of the yaw angle, the resultant wind speed, More >

Mengge Yu^{1, 2}, Zhenkuan Pan^{3, *}, Jiali Liu⁴, Haiqing Li¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 55-66, 2020, DOI:10.32604/fdmp.2020.07774 - 01 February 2020

Abstract The operational safety characteristics of trains exposed to a strong wind have caused great concern in recent years. In the present paper, the effect of the strong gust wind on a high-speed train is investigated. A typical gust wind model for any wind angle, named “Chinese hat gust wind model”, was first constructed, and an algorithm for computing the aerodynamic loads was elaborated accordingly. A vehicle system dynamic model was then set up in order to investigate the vehicle system dynamic characteristics. The assessment of the operational safety has been conducted by means of characteristic… More >

Yundong Han¹, Dawei Chen¹, Shaoqing Liu¹, Gang Xu²

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 1-19, 2020, DOI:10.32604/fdmp.2020.06525 - 01 February 2020

Abstract A series of tests have been conducted using a Cryogenic Wind Tunnel to study the effect of Reynolds number (Re) on the aerodynamic force and surface pressure experienced by a high speed train. The test Reynolds number has been varied from 1 million to 10 million, which is the highest Reynolds number a wind tunnel has ever achieved for a train test. According to our results, the drag coefficient of the leading car decreases with higher Reynolds number for yaw angles up to 30º. The drag force coefficient drops about 0.06 when Re is raised… More >

Tian Li^{1, *}, Zhiyuan Dai¹, Weihua Zhang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.2, pp. 555-570, 2020, DOI:10.32604/cmes.2020.08101 - 01 February 2020

Abstract Detached eddy simulation has been widely applied to simulate the flow around trains in recent years. The Reynolds-averaged Navier-Stokes (RANS) model for delayed detached eddy simulation (DDES) is an essential user input. The effect of the RANS model for DDES on the aerodynamic characteristics of a train in crosswinds is investigated in this study. Three different DDES models are used, based on the Spalart-Allmaras model (SA), the realizable k-ε model (RKE), and the shear stress transport k-ω model (SST). Results show that all DDES models can give relatively accurate predictions of pressure coefficient on almost all More >

Xing Deng^{1, 2}, Haijian Shao^{1, *}, Chunlong Hu¹, Dengbiao Jiang¹, Yingtao Jiang³

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 273-301, 2020, DOI:10.32604/cmes.2020.08768 - 01 January 2020

Abstract Accurate wind power forecasting in wind farm can effectively reduce the enormous impact on grid operation safety when high permeability intermittent power supply is connected to the power grid. Aiming to provide reference strategies for relevant researchers as well as practical applications, this paper attempts to provide the literature investigation and methods analysis of deep learning, enforcement learning and transfer learning in wind speed and wind power forecasting modeling. Usually, wind speed and wind power forecasting around a wind farm requires the calculation of the next moment of the definite state, which is usually achieved… More >