Three-Dimensional Aeroelastic Model for Successive Analyses of High-Aspect-Ratio Wings

Abstract Next-generation civil aircraft and atmospheric satellites will have high-aspect-ratio wings. Such a design necessitates successive analysis of static, frequency, and time-domain dynamic responses based on a three-dimensional nonlinear beam model. In this study, a new successive-analysis framework based on an absolute nodal coordinate formulation with mean artificial strains (ANCF-MAS) is developed. While retaining the advantages of other 3D ANCF approaches, such as constancy of the mass matrix and absence of velocity-dependent terms, ANCF-MAS uses the elastic force of the mean artificial strains to remove cross-sectional deformations that cause locking problems. The equation becomes a differential equation with an easily linearized elastic force that enables not only static and dynamic analyses but also frequency analysis using standard eigenvalue solvers. The solutions converge to the analytical frequencies without suffering from locking problems. A proposed successive-analysis method with model-order reduction reveals that the frequencies vary with the nonlinear static deformation because of the 3D deformation coupling. This reduced-order model agrees well with nonlinear models even when the wing experiences a large nonlinear dynamic deformation.

Download Full-text

Accelerating ion diffusion with unique three-dimensionally interconnected nanopores for self-membrane high-performance pseudocapacitors

Nanoscale ◽

10.1039/c7nr06234f ◽

2017 ◽

Vol 9 (46) ◽

pp. 18311-18317 ◽

Cited By ~ 5

Author(s):

Yuan Gao ◽

Yuanjing Lin ◽

Zehua Peng ◽

Qingfeng Zhou ◽

Zhiyong Fan

Keyword(s):

Aspect Ratio ◽

Surface Area ◽

Structural Stability ◽

High Aspect Ratio ◽

High Performance ◽

Three Dimensional ◽

Rate Capability ◽

Large Surface Area ◽

Nanoporous Structure ◽

Ion Diffusion

Three-dimensional interconnected nanoporous structure (3-D INPOS) possesses high aspect ratio, large surface area, as well as good structural stability. Profiting from its unique interconnected architecture, the 3-D INPOS pseudocapacitor achieves a largely enhanced capacitance and rate capability.

Download Full-text

Self-ordered nanospike porous alumina fabricated under a new regime by an anodizing process in alkaline media

Scientific Reports ◽

10.1038/s41598-021-86696-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mana Iwai ◽

Tatsuya Kikuchi ◽

Ryosuke O. Suzuki

Keyword(s):

Aspect Ratio ◽

High Aspect Ratio ◽

Porous Alumina ◽

Three Dimensional ◽

Alkaline Media ◽

Alkaline Electrolyte ◽

Subsequent Formation ◽

Interpore Distance ◽

Wide Range ◽

Ordered Porous

AbstractHigh-aspect ratio ordered nanomaterial arrays exhibit several unique physicochemical and optical properties. Porous anodic aluminum oxide (AAO) is one of the most typical ordered porous structures and can be easily fabricated by applying an electrochemical anodizing process to Al. However, the dimensional and structural controllability of conventional porous AAOs is limited to a narrow range because there are only a few electrolytes that work in this process. Here, we provide a novel anodizing method using an alkaline electrolyte, sodium tetraborate (Na2B4O7), for the fabrication of a high-aspect ratio, self-ordered nanospike porous AAO structure. This self-ordered porous AAO structure possesses a wide range of the interpore distance under a new anodizing regime, and highly ordered porous AAO structures can be fabricated using pre-nanotexturing of Al. The vertical pore walls of porous AAOs have unique nanospikes measuring several tens of nanometers in periodicity, and we demonstrate that AAO can be used as a template for the fabrication of nanomaterials with a large surface area. We also reveal that stable anodizing without the occurrence of oxide burning and the subsequent formation of uniform self-ordered AAO structures can be achieved on complicated three-dimensional substrates.

Download Full-text

High-aspect-ratio structure formation techniques for three-dimensional metal-oxide-semiconductor transistors

Microelectronic Engineering ◽

10.1016/j.mee.2006.01.270 ◽

2006 ◽

Vol 83 (4-9) ◽

pp. 1740-1744 ◽

Cited By ~ 1

Author(s):

Hideo Sunami ◽

Shunpei Matsumura ◽

Koji Yoshikawa ◽

Kiyoshi Okuyama

Keyword(s):

Aspect Ratio ◽

Metal Oxide ◽

Structure Formation ◽

High Aspect Ratio ◽

Three Dimensional ◽

Metal Oxide Semiconductor ◽

Oxide Semiconductor ◽

High Aspect Ratio Structure

Download Full-text

High-Aspect-Ratio Copper Via Filling Used for Three-Dimensional Chip Stacking

Journal of The Electrochemical Society ◽

10.1149/1.1572154 ◽

2003 ◽

Vol 150 (6) ◽

pp. G355 ◽

Cited By ~ 111

Author(s):

Jian-Jun Sun ◽

Kazuo Kondo ◽

Takuji Okamura ◽

SeungJin Oh ◽

Manabu Tomisaka ◽

...

Keyword(s):

Aspect Ratio ◽

High Aspect Ratio ◽

Three Dimensional

Download Full-text

Computational Fluid Dynamic Modelling of High Aspect Ratio Cross-Sectional Jets I: The Effect of Orifice Shape on Jet Behaviour

Emerging Technology in Fluids, Structures, and Fluid Structure Interactions ◽

10.1115/pvp2003-1950 ◽

2003 ◽

Author(s):

Sarah J. Wakes

Keyword(s):

Aspect Ratio ◽

High Aspect Ratio ◽

Cfd Simulation ◽

Fluid Dynamic ◽

Dynamic Modelling ◽

Common Belief ◽

Cross Sectional ◽

Numerical Work ◽

Hydrocarbon Production ◽

Gas Dispersion

High aspect ratio cross-sectional jets (HAR jets) are significant for many industrial applications including offshore hydrocarbon production safety, manufacturing processes, aeronautics and others. Little interest has been paid to such jets as the common belief was that within an acceptable distance from the jet orifice the behaviour emulates that of an axisymmetric jet. Previous experimental and preliminary numerical work [1–4] has shown that this is not necessarily correct. Work has been done to investigate numerically the effect the orifice shape has on the behaviour of the jets. This will be in terms of the curvature of the orifice in comparison to the same aspect ratio with a straight rectangular shape. Simulations have been carried out relating to experimental work [1] as comparison and verification. The spreading of the jet will be assessed as it can have significance in terms of safety, performance and effectiveness. This work enhances previous work [3] and allows an assessment of whether such a curvature in the inlet significantly effects the jet behaviour for two pipe pressures. The choice of turbulence model will also be assessed in terms of the standard two-equation k-ε model and it’s variants the RNG and Realisable models. Later work will investigate the use of Large Eddy Simulation within the context of the geometry used here. This important information will allow for greater understanding for the modelling of such jets in a CFD simulation within a complex industrial problem such as gas dispersion with a hydrocarbon production area. It is realized that the fluid does not emerge as a single velocity from the pipe into the flange and hence to form the inlet for the jet. Therefore the effect of the flow within the pipe and how this effects the emerging jet behaviour is investigated in part II of this paper [5].

Download Full-text

Strong and Reversible Adhesion of Interlocked 3D-Microarchitectures

Coatings ◽

10.3390/coatings9010048 ◽

2019 ◽

Vol 9 (1) ◽

pp. 48 ◽

Cited By ~ 1

Author(s):

Minho Seong ◽

Hyun-Ha Park ◽

Insol Hwang ◽

Hoon Eui Jeong

Keyword(s):

Aspect Ratio ◽

Structural Stability ◽

High Aspect Ratio ◽

Three Dimensional ◽

Normal Direction ◽

One Dimensional ◽

Reversible Adhesion ◽

Adhesion Behavior ◽

Organic Nanomaterials ◽

Good Agreement

Diverse physical interlocking devices have recently been developed based on one-dimensional (1D), high-aspect-ratio inorganic and organic nanomaterials. Although these 1D nanomaterial-based interlocking devices can provide reliable and repeatable shear adhesion, their adhesion in the normal direction is typically very weak. In addition, the high-aspect-ratio, slender structures are mechanically less durable. In this study, we demonstrate a highly flexible and robust interlocking system that exhibits strong and reversible adhesion based on physical interlocking between three-dimensional (3D) microscale architectures. The 3D microstructures have protruding tips on their cylindrical stems, which enable tight mechanical binding between the microstructures. Based on the unique 3D architectures, the interlocking adhesives exhibit remarkable adhesion strengths in both the normal and shear directions. In addition, their adhesion is highly reversible due to the robust mechanical and structural stability of the microstructures. An analytical model is proposed to explain the measured adhesion behavior, which is in good agreement with the experimental results.

Download Full-text