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Acta Oceanologica Sinica 2013年第9期32卷 11-20页

作者： NAM SungHyun PARK Young-Gyu Naval Systems development center Agency for Defense Development Ocean Circulation and Climate research Division Korea Institute of Ocean Science and Technology

Using a simple damped slab model, it was possible to show that a local wind induced 88% （15 of 17） of the near-inertial oscillations （NIO） observed in the mixed layer near the east coast of Korea from 1999 to 2004. The model, however, overestimated the energy level in about two-thirds of the simulated cases, because the slab model was forced with winds whose characteristic period was shorter than the damping time scale of the model at 1.5 d. At the observation site, due to typhoons and orographic effects, high-frequency wind forcing is quite common, as is the overestimation of the energy level in the slab model results. In short, a simple slab model with a damping time-scale of about 1.5 d would be enough to show that the local wind was the main energy source of the near-inertial energy in this area, but the model could not be used to accurately estimate the amount of the work done by the wind to the mixed layer.

关键词： near-inertial oscillations near-inertial waves slab model high-frequency wind forcing eastcoast of Korea

Plasma preparation and low-temperature sintering of spherical TiC –Fe composite powder

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1328-1333页

作者： Jian-jun Wang Jun-jie Hao Zhi-meng Guo Song Wang Institute for Advanced Materials and technology University of Science and Technology Beijing research and development center CSR Qingdao Sifang Co. Ltd.

A spherical Fe matrix composite powder containing a high volume fraction （82vo1%） of fine TiC reinforcement was produced using a novel process combining in situ synthesis and plasma techniques. The composite powder exhibited good sphericity and a dense structure, and the fine sub-micron TiC particles were homogeneously distributed in the α-Fe matrix. A TiC-Fe cermet was prepared from the as-prepared spherical composite powder using powder metallurgy at a low sintering temperature; the product exhibited a hardness of HRA 88.5 and a flexural strength of 1360 MPa. The grain size of the fine-grained TiC and special surface structure of the spherical powder played the key roles in the fabrication process.

关键词： powder technology cermets radio frequency plasma sintering numerical simulation

Microstructure and mechanical behavior of Inconel 625 alloy processed by selective laser melting at high temperature up to 1000℃

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Rare Metals 2020年第10期39卷 1181-1189页

作者： Xiao-An Hu Gao-Le Zhao Fen-Cheng Liu Wei-Xiong Liu School of Aircraft Engineering Nanchang Hangkong UniversityNanchang 330063China Airbreathing Hypersonic technology research center China Aerodynamic Research and Development CenterMianyang 621000China

Mechanical behavior of Inconel 625 alloy manufactured by selective laser melting(SLM)was experimentally *** tests were performed at various temperatures(20,540,760,815,870,950 and 1000℃).The microstructures and fracture mechanism were investigated using optical microscopy(OM),scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).The SLM Inconel 625 exhibits excellent plastic deformation at low ***,significant embrittlement for the SLM Inconel 625 was found at elevated temperatures compared to low temperature and traditional forging *** microstructure studies,the non-homogenous microstructure is a key factor causing the intergranular cracking mode at elevated ***,carbides were found to form at the grain boundary at elevated *** carbides could weaken the strength of the grain boundary at elevated temperatures,which decreased the tensile strength and ductility of the alloy processed by SLM.

关键词： Nickel-based superalloy Selective laser melting Embrittlement High temperature Microstructure

Active disturbance rejection distributed secondary control for DC microgrids

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High Voltage 2024年第1期9卷 241-251页

作者： Jianlin Li Honghao You Shuo Liu Xingchen Li Ziyang Ding Fei Zou National User-Side Energy Storage Innovation research and development center North China University of TechnologyBeijingChina

A novel control scheme is presented to eliminate the negative effects of communication disturbances,which introduces active disturbance rejection control(ADRC)in the control strategy design to achieve the objectives of the restoration of the bus voltage and the sharing of the power even in the presence of disturbances and delays in ***,its dynamic disturbance decoupling feature is used to realise the decoupling between power and voltage,so that the proposed controller only exchanges power information with its neighbours,reducing the communication burden and simplifying control *** control performance of the strategy is verified by employing steady-state *** impact of controller parameters is studied by establishing a small signal ***,both simulation cases and experimental tests prove the feasibility of this scheme.

关键词： Active disturbance establishing

Experimental research of air-throttling ignition for a scramjet at Ma 6.5

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Chinese Journal of Aeronautics 2017年第3期30卷 932-938页

作者： Weixin DENG Jialing LE Shunhua YANG Wanzhou ZHANG Ye TIAN Science and technology on Scramjet Lab Hypersonies Aerodynamics Institute China Aerodynamics Research and Development Center Mianyang 621000 China

An experimental investigation on ignition characteristics with air-throttling in an ethylene-fueled scramjet under flight Ma 6.5 conditions was *** dynamic process of air-throttling ignition was explored *** influences of throttling parameters,i.e.,throttling mass rate and duration,were *** the throttling mass rate was 45% of the inflow mass rate,ambient ethylene could be ignited *** delay time from ignition to throttling was about 45–55 *** was a threshold of throttling duration under a certain throttling mass *** was shorter than 100 ms when the throttling mass rate was 45%.While a 45%throttling mass rate would make the shock train propagate upstream to the isolator entry in about10–15 ms,four lower throttling mass rates were tested,including 30%,25%,20%,and 10%.All of these throttling mass rates could ignite ***,combustion performances varied with them.A higher throttling mass rate made more ethylene combust and produced higher wall *** these experiments,some aspects of the relationships between ignition,flame stabilization,combustion efficiency,and air-throttling parameters were brought to *** results could also be a benchmark for CFD validation.

关键词： Air-throttling Combustion Flame stabilization Ignition Scramjet Shock

Reliability design optimization of composite structures based on PSO together with FEA

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Chinese Journal of Aeronautics 2013年第2期26卷 343-349页

作者： Chen Jianqiao Tang Yuanfu Ge Rui An Qunli Guo Xiwei Department of Mechanics Huazhong University of Science and Technology research and development center Wuhan Iron and Steel (Group) Corp.

The present work aims to develop a method for reliability-based optimum design of composite structures. A procedure combining particle swarm optimization （PSO） and finite element analysis （FEA） has been proposed. Numerical examples for the reliability design optimization （RDO） of a laminate and a composite cylindrical shell are worked out to demonstrate the effectiveness of the method. Then a design for composite pressure vessels is studied. The advantages and necessity of RDO over the conventional equi-strength design are addressed. Examples show that the proposed method has good stability and is efficient in dealing with the probabilistic optimal design of composite structures. It may serve as an effective tool to optimize other complicated structures with uncertainties.

关键词： Composite structures FEA PSO Reliability analysis Reliability design optimization

Influence of syngas components and ash particles on the radiative heat transfer in a radiant syngas cooler

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Chinese Journal of Chemical Engineering 2024年第4期68卷 203-215页

作者： Chen Han Youmin Situ Huaxing Zhu Jianliang Xu Zhenghua Dai Guangsuo Yu Haifeng Liu National Energy Coal Gasification technology research and development center East China University of Science and TechnologyShanghai 200237China Shanghai Engineering research center of Coal Gasification East China University of Science and TechnologyShanghai 200237China

Radiant syngas cooler(RSC)is widely used as a waste heat recovery equipment in industrial *** this work,an RSC with radiation screens is established and the impact of gaseous radiative property models,gas components,and ash particles on heat transfer is investigated by the numerical simulation *** the syngas components and the pressure environment of the RSC,a modified weighted-sum-of-gray-gases model was *** modified model shows high accuracy in *** computational fluid dynamics simulation,the calculated steam production is only 0.63%in error with the industrial *** with Smith's model,the temperature decay along the axial direction calculated by the modified model is *** components are of great significance to heat recovery capacity,especially when the absorbing gas fraction is less than 10%.After considering the influence of particles,the outlet temperature and the proportion of radiative heat transfer are less affected,but the difference in steam output reaches 2.7 t·h^(-1).The particle deposition on the wall greatly reduces the heat recovery performance of an RSC.

关键词： Radiant syngas cooler Weighted-sum-of-gray-gases model Numerical simulation Particle radiation

Deuterium depth distribution study in Yb

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Chinese Physics C 2017年第5期41卷 104-108页

作者：关兴彩路咏凯何厚军赵江涛王强方开洪蒙萱王铁山 Jirohta Kasagi School of nuclear Science and technology Lanzhou University research center for Electron Photon Science Tohoku University

The deuterium depth distribution for a 20 keV/D D_3~＋beam implanted into ytterbium（Yb） at a temperature between 300 and 340 K was studied using the D（d,p）T *** analyzing the proton yields,the deuterium depth distribution from the front surface to 500 nm depth was *** results indicate that an equilibrium deuterium distribution region from the front surface to a depth approximately equal to the mean range of implanted deuterons was formed in Yb during the *** deduced deuterium concentration in the equilibrium deuterium distribution region was D/Yb = 22%.

关键词： proton implanted implantation isotopes deduced saturated saturation details nuclei transformed

Influences of regeneration atmospheres on structural transformation and renderability of fluidized catalytic cracking catalyst

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Chinese Journal of Chemical Engineering 2023年第11期63卷 71-80页

作者： Haigang Zhang Zhongjie Shen Jianhong Gong Haifeng Liu National Energy Coal Gasification technology research and development center and Shanghai Engineering research center of Coal Gasification East China University of Science and TechnologyShanghai 200237China Sinopec research Institute of Petroleum Processing Beijing 100083China

The regeneration of fluidized catalytic cracking(FCC)catalysts is an essential process in petroleum *** current study focused the regeneration reaction characteristics of spent fluidized catalytic cracking catalyst(SFCC)at different atmospheres with influences on pore evolution and activity,for a potential way to reduce emission,produce moderate chemical product(CO),and maintain catalyst *** results show that regeneration in air indicates a satisfaction on removing coke on the catalyst surface while giving a poor effect on eliminating the coke inside *** is attributed that the combustion in air led to a higher temperature and further transformed kaolinite phase to silicaaluminum spinel crystals,which tended to collapse and block small pores or expand large pores,with similar results observed in pure O_(2)***,catalysts regenerated in O_(2)/CO_(2)diminished the combustion damage to the pore structure,of which the micro porosity after regeneration increased by 32.4% and the total acid volume rose to 27.1%.The regeneration in pure CO_(2)displayed low conversion rate due to the endothermic reaction and low *** coexistence of gasification and partial oxidation can promote regeneration and maintain the original structure and good ***,a mechanism of the regeneration reaction at different atmospheres was revealed.

关键词： Fluidized catalytic cracking Coke deposit Regeneration Pore structure Gasification and combustion

High-order fully implicit SIMPLE-based model for fully implicit simulation of upward two-phase flow

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nuclear Science and Techniques 2018年第8期29卷 155-169页

作者： A.Hajizadeh H.Kazeminejad S.Talebi research School of Reactor Nuclear Science and Technology Research Institute research School of Radiation Applications Nuclear Science and Technology Research Institute Department of Energy Engineering and Physics Amirkabir University of Technology (Tehran Polytechnic)

The drift-flux model has a practical importance in two-phase flow *** this study,a finite volume solution is developed for a transient four-equation drift-flux model through the staggered mesh,leading to the development of a fully implicit discretization *** main advantage of the fully implicit method is its unconditional ***'s scheme is a popular method of choice for the solution of a nonlinear system of equations arising from fully implicit discretization of field ***,the lack of convergence robustness and the construction of Jacobian matrix have created several difficulties for the *** this paper,a fully implicit model is developed based on the SIMPLE algorithm for two-phase flow *** drawbacks of Newton's method are avoided in the developed *** limiter functions are considered,and the stabilized method is developed under steady and transient *** results obtained by the numerical modeling are in good agreement with the experimental *** expected,the results prove that the developed model is not restricted by any stability limit.

关键词：流动模型二阶模拟有限体积非线性飘移开发方程