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Chinese Journal of Aeronautics 2018年第6期31卷 1273-1286页

作者： Lulu LIU Zhenhua ZHAO Wei CHEN Gang LUO Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics

In this paper, ballistic impact tests on wrapped multi-layer Kevlar 49 woven fabric systems were carried out with a flat blade projectile to investigate the impact response during a fan blade out event. The influences of the number of Kevlar layers and pre-tension were discussed particularly. Test results were used to analyze failure modes and energy absorption characteristics of multi-ply Kevlar fabrics. Results show that there are two kinds of impact damage for fabrics： global deformation mainly involving stretching of yarns in the impact region and fabric wrinkle from both sides to the impact zone, and local damage characterized by yarn fracture, yarn pull-out, and yarn unraveling. The energy absorption capability of Kevlar 49 woven fabrics improves with the number of fabric layers. The energy absorbed by multi-layer fabrics increases slightly at the beginning and then decreases substantially with pre-tension. The work in this paper can provide guidance for designing light-weight multi-layer fabrics containment systems.

关键词： Energy absorption Fabrics Gas turbines Impact resistance multi-layers Pre-tension

Optimization Design of the multi-Layer Cross-Sectional Layout of An Umbilical Based on the GA-GLM

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China Ocean Engineering 2024年第2期38卷 247-254页

作者： YANG Zhi-xun YIN Xu FAN Zhi-rui YAN Jun LU Yu-cheng SU Qi MAO Yandong WANG Hua-lin Institute of marine machinery College of Mechanical and Electrical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDepartment of Engineering MechanicsDalian University of TechnologyDalian 116024China Ningbo Institube of Dalian University of Technology Ningbo 315040China

Marine umbilical is one of the key equipment for subsea oil and gas exploitation,which is usually integrated by a great number of different functional components with *** layout of these components directly affects manufacturing,operation and storage performances of the *** the multi-layer cross-sectional layout design of the umbilical,a quantifiable multi-objective optimization model is established according to the operation and storage *** the manufacturing factors,the multi-layering strategy based on contact point identification is introduced for a great number of functional ***,the GA-GLM global optimization algorithm is proposed combining the genetic algorithm and the generalized multiplier method,and the selection operator of the genetic algorithm is improved based on the steepest descent *** algorithm is used to find the optimal solution in the global space,which can converge from any initial layout to the feasible layout *** feasible layout solution is taken as the initial value of the generalized multiplier method for fast and accurate ***,taking umbilicals with a great number of components as examples,the results show that the cross-sectional performance of the umbilical obtained by optimization algorithm is better and the solution efficiency is ***,the multi-layering strategy is effective and *** design method proposed in this paper can quickly obtain the optimal multi-layer cross-sectional layout,which replaces the manual design,and provides useful reference and guidance for the umbilical industry.

关键词： umbilical cross-sectional layout multi-layers GA-GLM optimization

Laboratory investigation on hydraulic fracture propagation in sandstone-mudstone-shale layers

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Petroleum Science 2022年第4期19卷 1664-1673页

作者： Jiang-Chuan He Kuang-Sheng Zhang Han-Bin Liu Mei-Rong Tang Xue-Lin Zheng Guang-Qing Zhang PetroChina Changqing Oilfield Company Xi′an710018ShaanxiChina College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China

During the stimulating unconventional reservoirs, the vertical propagation of hydraulic fractures is crucial for enlarging the stimulated reservoir volume, especially in multi-layers of sandstone, mudstone and shale(sand-mud-shale). To investigate the effects of lithological interface and fracturing fluid viscosity on the fracture propagation vertically in the multi-layers, hydraulic fracturing experiments in laboratory were performed on the outcrop samples of 30 cm × 30 cm × 30 cm collected from Yanchang Formation in Ordos Basin. The results show that hydraulic fractures are multi-branched and zig-zagged when they initiate in shale, simple when they commence in sandstone or mudstone. Hydraulic fractures created with low-viscosity fracturing fluid can only cross sandstone from mudstone, but those induced by high-viscosity fracturing fluid can cross the sand-mud-shale layers. Furthermore, the high-viscosity fracturing fluid reduces the fractures complexity in shale, facilitating vertical fracture propagation. The injection pressure fluctuates slightly as the hydraulic fracture extends from shale to sandstone or mudstone, otherwise it fluctuates significantly. From the laboratory investigation, a hydraulic fracturing scheme for Chang 7 Member was proposed, with its feasibility proved in field tests.

关键词： Sandstone-mudstone-shale multi-layers Hydraulic fracturing experiments Lithological interface

Hydrogen storage properties of preferentially orientated Mg-Ni multilayer film prepared by magnetron sputtering

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Rare Metals 2006年第Z1期25卷 295-299页

作者： YE Suyun OUYANG Liuzhang ZHU Min College of Mechanical Engineering South China University of Technology Guangzhou 510640 China College of Mechanical Engineering South China University of Technology Guangzhou 510640 China College of Mechanical Engineering South China University of Technology Guangzhou 510640 China

Mg-Ni multi-layer thin film was deposited on (001) Si wafer by magnetron sputtering with dual-target. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis reveal that the microstructure of the Mg-Ni multilayer thin film is composed of fine-crystalline Ni layer and crystalline [001] Mg layer. Hydrogenation process of the films were carried out by using the automatic gas reaction controller. The films undergone hydrogenation for different time were analyzed by XRD. The results show that hydrogenation properties of Mg with different preferential orientations are different. (002) diffraction peak of Mg disappears in compensating the appearing of the peaks of Mg2NiH4 and MgH2 in hydrogenation at 533 K, while the (101) peak still remains. The result reveals that the Mg film with (001) preferential orientation absorbs hydrogen at certain temperature easier than that of the Mg film with (101) orientation. This phenomenon can be explained in the view point of the energy change for the nucleation and growth of hydride in different crystal plane.

关键词： hydrogen storage Mg-Ni film multi-layers magnetron sputtering

Acoustic Modeling of a 3-Layered Panel Incorporating Electro-Rheological/ Magneto-Rheological (EMR) Fluids

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Open Journal of Acoustics 2014年第1期4卷 1-12页

作者： Nader Mohammadi Department of Mechanical Engineering Islamic Azad University Parand Branch Tehran Iran

Applications of Electro-Rheological (ER) or Magneto-Rheological (MR) fluids as typical smart materials have been widely investigated over the past decades (since their introduction in 40’s). The special applications of these materials as a means of noise suppression are not yet investigated. Constrained Layer Damping (CLD) sheets can be realized by incorporating EMR (ER/MR) materials. In this way, a multilayered damping sheet is obtained with adaptive (tunable) stiffness and damping characteristics. These properties are easily changed in proportion to the electric (magnetic) field applied upon the EMR layer. This notion has been introduced for semi-active vibration control problems. Herein, such panels incorporating EMR material are proposed for adaptive acoustic treatments. Modeling (simulation) of a 3-layered panel with the middle layer being EMR with adjustable properties is carried out in this paper. The tunability of transmission/absorption characteristics of these composite sheets enables us making smart panels for adaptive noise and acoustic treatments. An adaptive performance can be achieved via changing the properties of such panels, on line, according to some sensor outputs. The main objective is to develop proper models to predict the Transmission Loss (TL) of such panels. Also, the TL of this panel is compared with the middle layer of a Newtonian fluid.

关键词： ER/MR Fluid multi-layers Panel Transmission Loss

Study of Optical Specifications of HfO2/Y2O3, Sc2O3+ MgO, and Ta2O5+ TiO2Used as Resonator Reflector for Nd:YAG Laser (1064 nm)

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Journal of Applied Mathematics and Physics 2020年第5期8卷 888-895页

作者： Esmat A.Amhed Mahasin A.Ahmed College of Electrical Engineering&IT Department of Electrical Engineering Onaizah CollegesKSA Department of Mathematics College of ScienceSudan University of Science and TechnologyKhartoumRepublic of Sudan

A theoretical design of a multi-layer for Nd:YAG mirrors resonator is described in this work. An output coupler was designed and fabricated by successive thin layers to achieve very high transmittance at optical wavelengths around 1064 nm for Nd:YAG mirrors resonator. The different film optical filters were used to control the transmittance and reflectance. The three samples of dielectric materials composed of HfO2/Y2O3, Sc2O3 + MgO, and Ta2O5 + TiO2 were used and compared with each other in transmittance, reflectance, full width at half maximum (FWHM), physical thickness, optical thickness, geometric thickness, and incident angles by the software [1].

关键词： Optical Filters Nd-YAG Laser Resonator multi-layers Thin Films