Mass-Optimized Design of Guyed Wind Turbine Tower Using Struts

Continuing upscaling trends in turbine height, rotor diameter, and rated power have resulted in massive, expensive tower structures. A modified guyed tower concept with struts (GTS) is proposed for saving material, and the basic design is made for a 2.5MW turbine. The tower and cable dimensions are optimized for lowest system cost given yield constraints. DACE (design and analysis of computer experiments) methods of sampling and surrogate model optimization are used for efficient parameter study and optimization of the ABAQUS finite element model using DAKOTA software. The resulting design is highly effective in transferring turbine loads from the tower to the cables. A mass savings of 41% is calculated vs. conventional structures, and further investigation of the GTS is recommended for both onshore and offshore applications. Additionally, the concept of retowering older turbines is introduced and proposed as an economic alternative to the common practice of repowering old wind farms with larger, new machines. The GTS is specifically suited to this application. Lastly, the design methodology developed for this study is shown to be effective and efficient; it can be applied for the massoptimization of similar cablesupported truss structures.

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Mechanical Stability of Hybrid Corrugated Sandwich Plates under Fluid-Structure-Thermal Coupling for Novel Thermal Protection Systems

Applied Sciences ◽

10.3390/app10082790 ◽

2020 ◽

Vol 10 (8) ◽

pp. 2790

Author(s):

Wenzheng Zhuang ◽

Chao Yang ◽

Zhigang Wu

Keyword(s):

Mechanical Stability ◽

Thermal Protection ◽

Element Model ◽

Parameter Study ◽

The Novel ◽

Thermal Coupling ◽

Mechanical Instability ◽

Fluid Structure ◽

Thermal Protection Systems ◽

Protection Systems

Hybrid corrugated sandwich (HCS) plates have become a promising candidate for novel thermal protection systems (TPS) due to their multi-functionality of load bearing and thermal protection. For hypersonic vehicles, the novel TPS that performs some structural functions is a potential method of saving weight, which is significant in reducing expensive design/manufacture cost. Considering the novel TPS exposed to severe thermal and aerodynamic environments, the mechanical stability of the HCS plates under fluid-structure-thermal coupling is crucial for preliminary design of the TPS. In this paper, an innovative layerwise finite element model of the HCS plates is presented, and coupled fluid-structure-thermal analysis is performed with a parameter study. The proposed method is validated to be accurate and efficient against commercial software simulation. Results have shown that the mechanical instability of the HCS plates can be induced by fluid-structure coupling and further accelerated by thermal effect. The influences of geometric parameters on thermal buckling and dynamic stability present opposite tendencies, indicating a tradeoff is required for the TPS design. The present analytical model and numerical results provide design guidance in the practical application of the novel TPS.

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Design of a New 45 kWe High-Flux Solar Simulator for High-Temperature Solar Thermal and Thermo-Chemical Research

Volume 5: Energy Systems Analysis, Thermodynamics and Sustainability; NanoEngineering for Energy; Engineering to Address Climate Change, Parts A and B ◽

10.1115/imece2010-40492 ◽

2010 ◽

Author(s):

Katherine R. Krueger ◽

Jane H. Davidson ◽

Wojciech Lipin´ski

Keyword(s):

High Temperature ◽

Focal Plane ◽

Flux Distribution ◽

Solar Thermal ◽

Optimized Design ◽

High Flux ◽

Chemical Research ◽

Solar Simulator ◽

Peak Flux ◽

The Common

In this paper, we present a systematic procedure to design a solar simulator for high-temperature concentrated solar thermal and thermo-chemical research. The 45 kWe simulator consists of seven identical radiation units of common focus, each comprised of a 6.5 kWe xenon arc lamp close-coupled to a precision reflector in the shape of a truncated ellipsoid. The size and shape of each reflector is optimized by a Monte Carlo ray tracing analysis to achieve multiple design objectives, including high transfer efficiency of radiation from the lamps to the common focal plane and desired flux distribution. Based on the numerical results, the final optimized design will deliver 7.5 kW over a 6-cm diameter circular disc located in the focal plane, with a peak flux approaching 3.7 MW/m2.

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Free Vibration Analysis for Tapered Cross-Section Steel-Concrete Composite Material Beam

Materials Science Forum ◽

10.4028/www.scientific.net/msf.893.380 ◽

2017 ◽

Vol 893 ◽

pp. 380-383

Author(s):

Jun Xia ◽

Z. Shen ◽

Kun Liu

Keyword(s):

Finite Element ◽

Composite Material ◽

Cross Section ◽

Vibration Analysis ◽

Free Vibration Analysis ◽

Element Model ◽

Composite Beams ◽

Shear Connection ◽

The Common ◽

Interlayer Slip

The tapered cross-section beams made of steel-concrete composite material are widely used in engineering constructions and their dynamic behavior is strongly influenced by the type of shear connection jointing the two different materials. The 1D high order finite element model for tapered cross-section steel-concrete composite material beam with interlayer slip was established in this paper. The Numerical results for vibration nature frequencies of the composite beams with two typical boundary conditions were compared with ANSYS using 2D plane stress element. The 1D element is more efficient and economical for the common tapered cross-section steel-concrete composite material beams in engineering.

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Optimized Design of Computer Experiments: A Review

Computational Methods for Engineering Technology ◽

10.4203/csets.35.13 ◽

2015 ◽

pp. 325-344

Author(s):

E. Mysakova ◽

A. Pospisilova ◽

M. Leps

Keyword(s):

Computer Experiments ◽

Optimized Design ◽

Design Of Computer Experiments

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On the optimized design of next-generation wind farms

European Journal of Operational Research ◽

10.1016/j.ejor.2020.10.048 ◽

2020 ◽

Author(s):

Martina Fischetti

Keyword(s):

Wind Farms ◽

Optimized Design ◽

Next Generation

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The Research for Extension Software Data Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.121-122.849 ◽

2010 ◽

Vol 121-122 ◽

pp. 849-853

Author(s):

Xiao Mao Wu ◽

Hui Ming Guo ◽

Yong Quan Yu

Keyword(s):

Data Structure ◽

Software Design ◽

Element Model ◽

Structure Model ◽

The Common ◽

Matter Element Model

In this paper, we analyze the data structure of design of matter-element model from the level of software design, combined with the features of the common used data structure and matter-element model in Extenics, finally propose a new data structure model, which adapt to computation, reasoning and transformation using matter-element model.

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Parameter study on a finite element model of the middle ear / Parameterstudie an einem Finite-Elemente-Modell des Mittelohrs

Biomedical Engineering / Biomedizinische Technik ◽

10.1515/bmt.2010.006 ◽

2010 ◽

Vol 55 (1) ◽

pp. 19-26 ◽

Cited By ~ 9

Author(s):

Marc Hoffstetter ◽

Florian Schardt ◽

Thomas Lenarz ◽

Sabine Wacker ◽

Erich Wintermantel

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Middle Ear ◽

Element Model ◽

Parameter Study ◽

Finite Elemente

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Experimental behaviour of concrete box culverts — comparison with current codes of practice

Canadian Geotechnical Journal ◽

10.1139/cgj-2018-0506 ◽

2019 ◽

Vol 56 (7) ◽

pp. 970-982 ◽

Cited By ~ 2

Author(s):

Nuno Cristelo ◽

Carlos Félix ◽

Joaquim Figueiras

Keyword(s):

Numerical Models ◽

Earth Pressure ◽

Element Model ◽

Structural Deformation ◽

Elastic Model ◽

Optimized Design ◽

Underground Structures ◽

State Highway ◽

Codes Of Practice ◽

Earth Pressures

It is now accepted that current expeditious models for determining earth pressures on flexible underground structures under compacted layers do not include several technical nuances of the soil–structure interaction. Thus, these models are not capable of delivering an optimized design. The present paper compares the results from the well-known American Association of State Highway and Transportation Officials (AASHTO) model with two different numerical models — a user-friendly elastic model and a more robust finite element model — and with results retrieved from a full-scale monitoring of a concrete box culvert, 5.5 m high and 3.77 m width, over which a 15 m high embankment was built. This structure was instrumented selectively, over a period of almost 1 year, during which several parameters were recorded, including earth pressures and structural deformation. Results have shown that the two most significant drawbacks associated with the use of the AASHTO model are the inadequate evaluation of vertical pressure on the top slab and the coefficient of earth pressure, which results in a significant overestimation of the lateral pressures and, consequently, in an overall inefficient design of the structure.

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Optimal design of shear vertical wave electromagnetic acoustic transducers in resonant mode

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209374 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 639-647

Author(s):

Zhichao Cai ◽

Zhenyong Zhao ◽

Lan Chen ◽

Guiyun Tian

Keyword(s):

Permanent Magnets ◽

Signal To Noise Ratio ◽

Acoustic Resonance ◽

Element Model ◽

Response Characteristic ◽

Resonant Mode ◽

Thickness Measurement ◽

Frequency Interval ◽

Resonant Amplitude ◽

The Common

In this paper, a new electromagnetic acoustic resonance (EMAR) transducer is proposed for precise thickness measurement in specimen. The new EMAR is composed of a mirror symmetric coil (MSC) and a pair of Nd-Fe-B permanent magnets with the different polarity for enhancing the generation and detection of resonant signals. Firstly, a finite element model was established to simulate the distributions of Lorentz force produced by new EMAR and the resonant process of shear waves. Furthermore, the relationship between the frequency response characteristic of the new EMAR and the common EMAR were explored. Finally, to verify the performance of the EMAR, several experiments were performed. Compared with the common EMAR transducer, the resonant amplitude of the new EMAR transducer was increased by 121.74% and the signal-to-noise ratio was increased by 28.35%, and the resonance frequency interval of the new EMAR was twice that of the common mode in the frequency domain simulation experiment, this advantage effectively reduced the error rate of measurement. The results show that the new EMAR transducer with mirror coil structure has higher accuracy in thickness detection of specimens.

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