Lin Wang¹, Chunguo An², Nini Wang², Yaming Ping¹, Kun Wang¹, Ming Gao^1,*, Suoying He¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.3, pp. 585-600, 2020, DOI:10.32604/fdmp.2020.09611

Abstract Numerical simulation are conducted to explore the characteristics of the axial inflow and related aerodynamic noise for a large-scale adjustable fan with the installation angle changing from −12° to 12°. In such a range the maximum static (gauge) pressure at the inlet changes from −2280 Pa to 382 Pa, and the minimum static pressure decreases from −3389 Pa to −8000 Pa. As for the axial intermediate flow surface, one low pressure zone is located at the junction of the suction surface and the hub, another is located at the suction surface close to the casing position. At the outlet boundary,… More >

Ajay Veludurthi¹, Venkateshwarlu Bolleddu^2,*

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

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 boundary conditions are applied. The… 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 through histogram features. In this… More >

TARSILA MARIA DA SILVA MORAES¹, CLAUDIA FRANCA BARROS², SEBASTIÃO JOSÉ DA SILVA NETO³, VALDIRENE MOREIRA GOMES⁴, MAURA DA CUNHA^1*

BIOCELL, Vol.33, No.3, pp. 155-165, 2009, DOI:10.32604/biocell.2009.33.155

Abstract Simira is a predominantly woody Neotropical genus comprising 41 taxa, 16 of which occur in Brazil and eight of them in the southeastern region of Brazil. Leaf blades of Simira eliezeriana Peixoto, S. glaziovii (K. Schum.) Steyerm., S. grazielae Peixoto, S. pikia (K. Schum.) Steyerm., S. rubra (Mart.) Steyerm., S. sampaioana (Standl.) Steyerm. were collected in the southeastern region of Brazil and fixed according to usual methods for light and electron microscopy. The leaf blades show typical characteristics of the Rubiaceae family as dorsiventral mesophyll and paracytic stomata. The presence of two bundle sheaths that extend to the upper epidermal… 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 length (LL) and above… 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 active vibration control. Simulation results… More >

Wei LIU, Jiacong YIN, Pu CHEN, Xianyue SU

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 127-128, 2011, DOI:10.3970/icces.2011.017.127

Abstract In this paper, parametric modeling technique is employed to fast build the three-dimensional finite element shell model of a preliminarily designed large composite wind turbine blade, which is subsequently used in the dynamic analysis and static elastic aeroelastic stability analysis of the blade. In the dynamic analysis, natural frequencies and corresponding modal shapes are obtained for the blade in the case of being still as well as being rotating with rated revolution. For the rotating blade, the stress stiffening effect and spin-softening effect due to the centrifugal forces are taken into account. The static elastic aeroelastic stability analysis, i.e. buckling… More >

R. A. Tough^1,2, A. M. Tousi², J. Ghaffari²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.14, No.1, pp. 1-22, 2010, DOI:10.3970/icces.2010.014.001

Abstract In this paper, micro-turbine centrifugal impeller with three different blade angles was investigated by using Computational Fluid Dynamics (CFD) method. The other basic geometric parameters are held constant. The influence of the blade angles change on the observed values was determined from numerical solution of the flow in the impeller with help of the FLUENT software. The numerical simulation focused on the air flow from compressor impeller inlet to exit, and the performance of impeller is predicted. The numerical solution was performed for original impeller geometry and for two other cases, in which blade inlet angle and backward sweep was… 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. Secondly, a one-way partitioned FSI… 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 discretization, we adopted a domain… More >