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期刊论文 11

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2022 3

2020 1

2015 1

2013 1

2011 1

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SPH 1

“五维”拥堵指数 1

个人热管理 1

二维非线性动力学 1

双功能非对称织物 1

固体氧化物燃料电池 1

导电机理 1

数值模拟 1

热传导 1

热传导模型 1

热辐射 1

电导率 1

电极 1

电解质 1

织物 1

负荷度评价 1

路网实时动态评价 1

递延传导效应 1

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Ion conduction path in composite solid electrolytes for lithium metal batteries: from polymer rich to

Zhouyu ZHANG, Hao CHEN, Zhenglin HU, Shoubin ZHOU, Lan ZHANG, Jiayan LUO

《能源前沿（英文）》 2022年第16卷第5期页码 706-733 doi: 10.1007/s11708-022-0833-9

摘要： Solid-state electrolytes (SSEs) can address the safety issue of organic electrolyte in rechargeable lithium batteries. Unfortunately, neither polymer nor ceramic SSEs used alone can meet the demand although great progress has been made in the past few years. Composite solid electrolytes (CSEs) composed of flexible polymers and brittle but more conducting ceramics can take advantage of the individual system for solid-state lithium metal batteries (SSLMBs). CSEs can be largely divided into two categories by the mass fraction of the components: “polymer rich” (PR) and “ceramic rich” (CR) systems with different internal structures and electrochemical properties. This review provides a comprehensive and in-depth understanding of recent advances and limitations of both PR and CR electrolytes, with a special focus on the ion conduction path based on polymer-ceramic interaction mechanisms and structural designs of ceramic fillers/frameworks. In addition, it highlights the PR and CR which bring the leverage between the electrochemical property and the mechanical property. Moreover, it further prospects the possible route for future development of CSEs according to their rational design, which is expected to accelerate the practical application of SSLMBs.

关键词： composite solid electrolytes active filler/framework ion conduction path interphase compatibility multilayer design

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An invariant descriptor for conjugate forced convection-conduction cooling of 3D protruding heaters in

Thiago ANTONINI ALVES,Paulo H. D. SANTOS,Murilo A. BARBUR

《机械工程前沿（英文）》 2015年第10卷第3期页码 263-276 doi: 10.1007/s11465-015-0345-y

摘要：

In this research, the temperatures of three-dimensional (3D) protruding heaters mounted on a conductive substrate in a horizontal rectangular channel with laminar airflow are related to the independent power dissipation in each heater by using a matrix G⁺ with invariant coefficients, which are dimensionless. These coefficients are defined in this study as the conjugate influence coefficients (g⁺) caused by the forced convection-conduction nature of the heaters’ cooling process. The temperature increase of each heater in the channel is quantified to clearly identify the contributions attributed to the self-heating and power dissipation in the other heaters (both upstream and downstream). The conjugate coefficients are invariant with the heat generation rate in the array of heaters when assuming a defined geometry, invariable fluid and flow rate, and constant substrate and heater conductivities. The results are numerically obtained by considering three 3D protruding heaters on a two-dimensional (2D) array by ANSYS/Fluent^TM 15.0 software. The conservation equations are solved by a coupled procedure within a single calculation domain comprising of solid and fluid regions and by considering a steady state laminar airflow with constant properties. Some examples are shown, indicating the effects of substrate thermal conductivity and Reynolds number on conjugate influence coefficients.

关键词： channel flow conjugate forced convection-conduction cooling conjugate influence coefficients discrete heating invariant descriptor thermal management

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Numerical study of conduction and radiation heat losses from vacuum annulus in parabolic trough receivers

Dongqiang LEI, Yucong REN, Zhifeng WANG

《能源前沿（英文）》 2022年第16卷第6期页码 1048-1059 doi: 10.1007/s11708-020-0670-7

摘要： Parabolic trough receiver is a key component to convert solar energy into thermal energy in the parabolic trough solar system. The heat loss of the receiver has an important influence on the thermal efficiency and the operating cost of the power station. In this paper, conduction and radiation heat losses are analyzed respectively to identify the heat loss mechanism of the receiver. A 2-D heat transfer model is established by using the direct simulation Monte Carlo method for rarefied gas flow and heat transfer within the annulus of the receiver to predict the conduction heat loss caused by residual gases. The numerical results conform to the experimental results, and show the temperature of the glass envelope and heat loss for various conditions in detail. The effects of annulus pressure, gas species, temperature of heat transfer fluid, and annulus size on the conduction and radiation heat losses are systematically analyzed. Besides, the main factors that cause heat loss are analyzed, providing a theoretical basis for guiding the improvement of receiver, as well as the operation and maintenance strategy to reduce heat loss.

关键词： parabolic trough receiver vacuum annulus rarefied gas DSMC (direct simulation Monte Carlo) heat loss

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Sensitivity analysis and numerical experiments on transient test of compact heat exchanger surfaces

REN Hesheng, LAI Lingjun, CUI Yongzheng

《能源前沿（英文）》 2008年第2卷第4期页码 374-380 doi: 10.1007/s11708-008-0079-1

摘要： A single-blow transient testing technique considering the effect of longitudinal heat conduction is suggested for determining the average convection heat transfer coefficient of compact heat exchanger surface. By matching the measured outlet fluid temperature variation with similar theoretical curves, the dimensionless longitudinal conduction parameter , the time constant of the inlet fluid temperature , and the number of heat transfer units can be determined simultaneously using the Levenberg-Marquardt nonlinear parameter estimation method. Both sensitivity analysis and numerical experiments with simulated measurements containing random errors show that the method in the present investigation provides satisfactory accuracy of the estimated parameter , which characterizes the heat transfer performance of compact heat exchanger surfaces.

关键词： coefficient dimensionless longitudinal longitudinal temperature conduction

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SPH原理、发展现状及热传导问题模型

王玉恒,刘峰,宋凤梅

《中国工程科学》 2008年第10卷第11期页码 47-51

摘要：

对光滑粒子流体动力学方法（smoothed particle hydrodynamics,SPH）的基本技术原理及发展现状进行了综述，利用SPH方法对两个典型二维非线性动力学算例进行了数值模拟。同时，利用国外学者提出的方法初步探索了有关热传导问题的SPH模型。

关键词： SPH 二维非线性动力学热传导模型数值模拟

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Monte Carlo simulation of the PEMFC catalyst layer

WANG Hongxing, CAO Pengzhen, WANG Yuxin

《化学科学与工程前沿（英文）》 2007年第1卷第2期页码 146-150 doi: 10.1007/s11705-007-0027-3

摘要： The performance of the polymer electrolyte membrane fuel cell (PEMFC) is greatly controlled by the structure of the catalyst layer. Low catalyst utilization is still a significant obstacle to the commercialization of the PEMFC. In order to get a fundamental understanding of the electrode structure and to find the limiting factor in the low catalyst utilization, it is necessary to develop the mechanical model on the effect of catalyst layer structure on the catalyst utilization and the performance of the PEMFC. In this work, the structure of the catalyst layer is studied based on the lattice model with the Monte Carlo simulation. The model can predict the effects of some catalyst layer components, such as Pt/C catalyst, electrolyte and gas pores, on the utilization of the catalyst and the cell performance. The simulation result shows that the aggregation of conduction grains can greatly affect the degree of catalyst utilization. The better the dispersion of the conduction grains, the larger the total effective area of the catalyst is. To achieve higher utilization, catalyst layer components must be distributed by means of engineered design, which can prevent aggregation.

关键词： catalyst utilization PEMFC commercialization Pt/C catalyst conduction

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用于个人降温和保暖的具有定制热传导和热辐射特性的双功能非对称织物 Article

Yucan Peng, Hiang Kwee Lee, David S. Wu, Yi Cui

《工程（英文）》 2022年第10卷第3期页码 167-173 doi: 10.1016/j.eng.2021.04.016

摘要：

为了让人体感到热舒适，同时节约能源，个人热管理正逐渐成为一种颇有前景的策略。通过更好地控制人体散热，个人热管理可以实现有效的个人降温和保暖。本文提出了一种简单的表面改性方法，在商用织物的基础上定制热传导和热辐射特性，以便更好地管理从人体到环境的整个传热路径。本文对一种同时具有降温和保暖效果的双功能非对称织物（BAF）进行论证。凭借粗糙度不对称和表面改性等优点，BAF在降温模式下通过增强热传导和热辐射表现出显著的降温效果；在保暖模式下，两条路径的散热都减少，从而实现个人保暖。结果表明，在BAF的降温和保暖模式下测得的皮肤温差可达4.6 ℃，表明一件BAF衣服可以扩大人体的热舒适区。希望本研究可为用于个人热管理的织物的设计提供新的视角，并为现有的用于个人降温和保暖的织物的简单改性提供新的解决方案。

关键词：织物个人热管理双功能非对称织物热传导热辐射

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Modeling of ion conductivity in Nafion membranes

YANG Zhen, PENG Xiaofeng, WANG Buxuan, DUAN Yuanyuan, LEE Duujong

《能源前沿（英文）》 2007年第1卷第1期页码 58-66 doi: 10.1007/s11708-007-0005-y

摘要： A theoretical investigation was conducted to describe the ion transport behavior in a Nafion Membrane of proton exchange membrane fuel cells (PEMFC). By analyzing the surface energy configuration of the ionic clusters in a Nafion membrane, an equivalent field intensity, , was introduced to facilitate the analysis of surface resistance against ion conduction in the central region of clusters. An expression was derived for ionic conductivity incorporating the influence of surface resistance. A face-centered cubic (FCC) lattice model for a spatial cluster distribution was used to modify the effect of water content on ionic conductivity in the polymeric matrix, i.e., the regions between clusters. Compared with the available empirical correlations, the new expression showed much better agreement with the available experimental results, which indicates the rationality to consider the structural influence on ion conduction in water-swollen Nafion membranes.

关键词： face-centered polymeric theoretical investigation conduction equivalent

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固体氧化物燃料电池的电解质及电极材料的电导率研究方法

贺贝贝,潘鑫,夏长荣

《中国工程科学》 2013年第15卷第2期页码 57-65

摘要：

论述了晶体材料，重点是固体氧化物燃料电池组件的导电机理，介绍了影响电导率的几个因素。针对不同的电解质和电极材料，讨论了几种常用的测量电解质和电极总电导率、电子电导率以及离子电导率的方法，并指出在测量中需要注意的问题。

关键词：导电机理电解质电极电导率固体氧化物燃料电池

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An isogeometric numerical study of partially and fully implicit schemes for transient adjoint shape sensitivity analysis

Zhen-Pei WANG, Zhifeng XIE, Leong Hien POH

《机械工程前沿（英文）》 2020年第15卷第2期页码 279-293 doi: 10.1007/s11465-019-0575-5

摘要： In structural design optimization involving transient responses, time integration scheme plays a crucial role in sensitivity analysis because it affects the accuracy and stability of transient analysis. In this work, the influence of time integration scheme is studied numerically for the adjoint shape sensitivity analysis of two benchmark transient heat conduction problems within the framework of isogeometric analysis. It is found that (i) the explicit approach ( = 0) and semi-implicit approach with <0.5 impose a strict stability condition of the transient analysis; (ii) the implicit approach ( =1) and semi-implicit approach with > 0.5 are generally preferred for their unconditional stability; and (iii) Crank–Nicolson type approach ( =0.5) may induce a large error for large time-step sizes due to the oscillatory solutions. The numerical results also show that the time-step size does not have to be chosen to satisfy the critical conditions for all of the eigen-frequencies. It is recommended to use for unconditional stability, such that the oscillation condition is much less critical than the Crank–Nicolson scheme, and the accuracy is higher than a fully implicit approach.

关键词： isogeometric shape optimization design-dependent boundary condition transient heat conduction implicit time integration adjoint method

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城市道路网运行实时动态评价理论和技术研究

全永燊,郭继孚,温慧敏,孙建平

《中国工程科学》 2011年第13卷第1期页码 43-48

摘要：

从道路网运行的基本特性入手，着重分析了路网运行的随机波动性、递延传导效应和周期规律性。在此基础上，剖析了迄今国内外一直沿用的道路“负荷度”路网评价理论的局限性，提出一套适用于路网整体实时动态评价的理论和技术方法，解决了无盲区实时数据采集与处理、路网运行时空动态分析、评价指标阈值标定等关键技术难题，为交通战略规划、实时动态路网功况诊断等提供了全新的技术手段，北京市的实证研究初步证明了所提出的理论和技术体系科学、有效、实用。

关键词：路网实时动态评价负荷度评价递延传导效应 “五维”拥堵指数