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 >

Nian Wang, Mingjie Zhang, Sulaiman Alsaleem, Lesley M. Wright, Je-Chin Han^*

Frontiers in Heat and Mass Transfer, Vol.13, pp. 1-13, 2019, DOI:10.5098/hmt.13.9

Abstract This study investigates turbine blade, leading edge cooling from normal or tangential impinging jets. These jets impinging on a semi-cylindrical, inner surface are constrained to discharge in a single direction. The downstream jets are affected by the crossflow originating from the upstream jets. To understand the thermal flow physics, numerical simulations are performed using the realizable k- turbulence model. Both the experimental and numerical results show crossflow is more detrimental to normal impinging jets than the tangential jets. Furthermore, with a significant temperature drop across the jet plate, designers must correctly interpret jet impingement results. More >

A. Joshuva^1,*, V. Sugumaran²

Structural Durability & Health Monitoring, Vol.13, No.4, pp. 399-416, 2019, DOI:10.32604/sdhm.2019.03014

Abstract Wind energy is considered as a alternative renewable energy source due to its low operating cost when compared with other sources. The wind turbine is an essential system used to change kinetic energy into electrical energy. Wind turbine blades, in particular, require a competitive condition inspection approach as it is a significant component of the wind turbine system that costs around 20-25 percent of the total turbine cost. The main objective of this study is to differentiate between various blade faults which affect the wind turbine blade under operating conditions using a machine learning approach… More >

Yinhu Qiao^1,*, Chunyan Zhang¹, Jiang Han²

Sound & Vibration, Vol.53, No.1, pp. 14-24, 2019, DOI:10.32604/sv.2019.04120

Abstract This paper presents a theoretical analysis of vibration control technology of wind turbine blades made of piezoelectric intelligent structures. The design of the blade structure, which is made from piezoelectric material, is approximately equivalent to a flat shell structure. The differential equations of piezoelectric shallow shells for vibration control are derived based on piezoelectric laminated shell theory. On this basis, wind turbine blades are simplified as elastic piezoelectric laminated shells. We establish the electromechanical coupling system dynamic model of intelligent structures and the dynamic equation of composite piezoelectric flat shell structures by analyzing simulations of More >

Shunhua Chen^1,*, Shinobu Yoshimura¹, Kaworu Yodo², Naoto Mitsume¹, Yasunori Yusa³, Tomonori Yamada¹, Chisachi Kato⁴, Shori Orimo⁴, Yoshinobu Yamade⁵, Akiyoshi Iida⁶

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.3, pp. 60-60, 2019, DOI:10.32604/icces.2019.05361

Abstract With the pressing requirement of wind energy capacity, the wind turbine blade size has been getting larger and larger in recent decades. For such a large-size blade, it is of prime importance to accurately evaluate the mechanical response under various wind loading conditions. In this work, we present a computational framework to achieve this end. Firstly, a finite element model for a 5MW blade is established according to the well-known NREL report. A composite laminated element is adopted to describe the blade structure. The effectiveness of this model is validated by means of eigenfrequency analysis.… More >

Yasunori Yusa^1,*, Tomoshi Miyamura², Tomonori Yamada³, Shinobu Yoshimura³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.3, pp. 58-58, 2019, DOI:10.32604/icces.2019.05231

Abstract In a wind turbine blade, laminated plates consisting of fiber reinforced plastic materials are generally used due to its high specific strength. We have been developing a large-scale finite element solver to analyze the wind turbine blade structure. For such a structure, the laminated finite element is frequently used in modeling. Each laminated finite element has multiple layers, each of which is an orthotropic body in order to model the layered fiber reinforced materials with different fiber directions. Also, since a realistic wind turbine blade structure generally requires a large number of finite elements for… More >

A. Joshuva¹, V. Sugumaran²

Structural Durability & Health Monitoring, Vol.13, No.2, pp. 181-203, 2019, DOI:10.32604/sdhm.2019.00287

Abstract Wind turbine blades are generally manufactured using fiber type material because of their cost effectiveness and light weight property however, blade get damaged due to wind gusts, bad weather conditions, unpredictable aerodynamic forces, lightning strikes and gravitational loads which causes crack on the surface of wind turbine blade. It is very much essential to identify the damage on blade before it crashes catastrophically which might possibly destroy the complete wind turbine. In this paper, a fifteen tree classification based machine learning algorithms were modelled for identifying and detecting the crack on wind turbine blades. The More >

Ferri CM, VV Jouve, AM Sáenz

Phyton-International Journal of Experimental Botany, Vol.86, pp. 190-198, 2017, DOI:10.32604/phyton.2017.86.190

Abstract The defoliation frequency determines above and below ground biomass accumulation, pasture structure and nutritive value. Two defoliation experiments with Panicum coloratum were performed, from September to March. One of them was conducted in pots under greenhouse conditions, and the other one in field plots for three growing seasons (EC) at the Faculty of Agronomy, La Pampa, Argentina (36˚ 46' S; 64˚ 16' W). Defoliation frequency treatments were four cutting intervals (IC; 3, 4, 6 and 8 weeks). In greenhouse experiment, live leaf blade accumulation rates (TAL), tiller appearance (TAM) and death (TMM) rates, live leaf blade… More >

A. Joshuva¹, V. Sugumaran²

Structural Durability & Health Monitoring, Vol.11, No.1, pp. 69-90, 2017, DOI:10.3970/sdhm.2017.012.069

Abstract Renewable energy sources are considered much in energy fields because of the contemporary energy calamities. Among the important alternatives being considered, wind energy is a durable competitor because of its dependability due to the development of the innovations, comparative cost effectiveness and great framework. To yield wind energy more proficiently, the structure of wind turbines has turned out to be substantially bigger, creating conservation and renovation works troublesome. Due to various ecological conditions, wind turbine blades are subjected to vibration and it leads to failure. If the failure is not diagnosed early, it will lead… More >

G. Frulla¹, P. Gili¹, M. Visone², V. D’Oriano^2,3, M. Lappa⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.3, pp. 257-277, 2015, DOI:10.3970/fdmp.2015.011.257

Abstract A practical engineering approach to the design of a 60 kW wind generator with improved performances is presented. The proposed approach relies on the use of a specific, "ad hoc'' developed software, OPTIWR (Optimization Software), expressly conceived to define an "optimum'' rotor configuration in the framework of the blade-element-momentum theory. Starting from an initial input geometric configuration (corresponding to an already existing 50 kW turbine) and for given values of the wind velocity V_wind and of the advance ratio X = V_wind/ΩR (where Ω is the blade rotational speed and R is the propeller radius), this software… More >