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FY-3湿度仪 1

主支式厨房排烟道 1

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抛物型缓坡方程；波浪破碎区；辐射应力；沿岸流；污染物 1

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Ag/PMMA hollow waveguide for solar energy transmission

He LAN, Jianjun HAN, Hongping CHEN, Xiujian ZHAO

《化学科学与工程前沿（英文）》 2011年第5卷第3期页码 303-307 doi: 10.1007/s11705-010-0565-y

摘要： This paper describes an elaborate study on obtaining Ag/PMMA (polymethyl methacrylate) leaky hollow waveguide which has a large aperture and low loss in transmitting solar energy. Through analyses and comparison, a quartz capillary with the inner diameter of 2 mm was chosen as hollow waveguide. We used the xenon light source, which has the similar spectrum as the sunlight to test and analyze the performance of the Ag/PMMA leakage hollow waveguide. The results are consistent with the transmitted theory of the dielectric/metal leaky type well. Meanwhile, the Ag/PMMA leaky-type hollow waveguide in this work had good qualities. Therefore, it will be a satisfactory medium for solar energy transmission.

关键词： hollow waveguide transmit the solar energy Ag/PMMA multiple film parabolic collector

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Effects of critical geometric parameters on the optical performance of a conical cavity receiver

Hu XIAO, Yanping ZHANG, Cong YOU, Chongzhe ZOU, Quentin FALCOZ

《能源前沿（英文）》 2019年第13卷第4期页码 673-683 doi: 10.1007/s11708-019-0630-2

摘要： The optical performance of a receiver has a great influence on the efficiency and stability of a solar thermal power system. Most of the literature focuses on the optical performance of receivers with different geometric shapes, but less research is conducted on the effects of critical geometric parameters. In this paper, the commercial software TracePro was used to investigate the effects of some factors on a conical cavity receiver, such as the conical angle, the number of loops of the helical tube, and the distance between the focal point of the collector and the aperture. These factors affect the optical efficiency, the maximum heat flux density, and the light distribution in the conical cavity. The optical performance of the conical receiver was studied and analyzed using the Monte Carlo ray tracing method. To make a reliable simulation, the helical tube was attached to the inner wall of the cavity in the proposed model. The results showed that the amount of light rays reaching the helical tube increases with the increasing of the conical angle, while the optical efficiency decreases and the maximum heat flux density increases. The increase in the number of loops contributed to an increase in the optical efficiency and a uniform light distribution. The conical cavity receiver had an optimal optical performance when the focal point of the collector was near the aperture.

关键词： parabolic collector conical cavity receiver critical geometric parameters optical performance

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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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Potential of performance improvement of concentrated solar power plants by optimizing the parabolic trough

Honglun YANG, Qiliang WANG, Jingyu CAO, Gang PEI, Jing LI

《能源前沿（英文）》 2020年第14卷第4期页码 867-881 doi: 10.1007/s11708-020-0707-y

摘要： This paper proposes a comprehensive thermodynamic and economic model to predict and compare the performance of concentrated solar power plants with traditional and novel receivers with different configurations involving operating temperatures and locations. The simulation results reveal that power plants with novel receivers exhibit a superior thermodynamic and economic performance compared with traditional receivers. The annual electricity productions of power plants with novel receivers in Phoenix, Sevilla, and Tuotuohe are 8.5%, 10.5%, and 14.4% higher than those with traditional receivers at the outlet temperature of 550°C. The levelized cost of electricity of power plants with double-selective-coated receivers can be decreased by 6.9%, 8.5%, and 11.6%. In Phoenix, the optimal operating temperature of the power plants is improved from 500°C to 560°C by employing a novel receiver. Furthermore, the sensitivity analysis of the receiver heat loss, solar absorption, and freeze protection temperature is also conducted to analyze the general rule of influence of the receiver performance on power plants performance. Solar absorption has a positive contribution to annual electricity productions, whereas heat loss and freeze protection temperature have a negative effect on electricity outputs. The results indicate that the novel receiver coupled with low melting temperature molten salt is the best configuration for improving the overall performance of the power plants.

关键词： concentrated solar power parabolic trough receiver heat loss solar energy annual performance

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Elastic analysis of heterogeneous thick-walled spherical pressure vessels with parabolic varying properties

Keyhan KARAMI, Majid ABEDI, Mohammad ZAMANI NEJAD, Mohammad Hassan LOTFIAN

《机械工程前沿（英文）》 2012年第7卷第4期页码 433-438 doi: 10.1007/s11465-012-0336-1

摘要：

On the basis of plane elasticity theory (PET), the displacement and stress components in a thick-walled spherical pressure vessels made of heterogeneous materials subjected to internal and external pressure is developed. The mechanical properties except the Poisson’s ratio are assumed to obey the parabolic variations throughout the thickness. Effect of material inhomogeneity on the elastic deformations and stresses is investigated. The analytical solutions and the solutions carried out through the FEM have a good agreement. The values used in this study are arbitrary chosen to demonstrate the effect of inhomogeneity on displacements, and stresses distributions.

关键词： thick-walled spherical vessels heterogeneous materials FGM FEM parabolic varying properties

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Thermal and hydraulic characteristics of a large-scaled parabolic trough solar field (PTSF) under cloud

Linrui MA, Zhifeng WANG, Ershu XU, Li XU

《能源前沿（英文）》 2020年第14卷第2期页码 283-297 doi: 10.1007/s11708-019-0649-4

摘要： To better understand the characteristics of a large-scaled parabolic trough solar field (PTSF) under cloud passages, a novel method which combines a closed-loop thermal hydraulic model (CLTHM) and cloud vector (CV) is developed. Besides, the CLTHM is established and validated based on a pilot plant. Moreover, some key parameters which are used to characterize a typical PTSF and CV are presented for further simulation. Furthermore, two sets of results simulated by the CLTHM are compared and discussed. One set deals with cloud passages by the CV, while the other by the traditionally distributed weather stations (DWSs). Because of considering the solar irradiance distribution in a more detailed and realistically way, compared with the distributed weather station (DWS) simulation, all essential parameters, such as the total flowrate, flow distribution, outlet temperature, thermal and exergetic efficiency, and exergetic destruction tend to be more precise and smoother in the CV simulation. For example, for the runner outlet temperature, which is the most crucial parameter for a running PTSF, the maximum relative error reaches −15% in the comparison. In addition, the mechanism of thermal and hydraulic unbalance caused by cloud passages are explained based on the simulation.

关键词： parabolic trough solar field (PTSF) thermal hydraulic model cloud passages transients

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Numerical simulation and experiment research of radiation performance in a dish solar collector system

Yong SHUAI, Xinlin XIA, Heping TAN

《能源前沿（英文）》 2010年第4卷第4期页码 488-495 doi: 10.1007/s11708-010-0007-z

摘要： The Monte Carlo ray-tracing method is applied and coupled with optical properties to predict the radiation performance of solar concentrator/cavity receiver systems. Several different cavity geometries are compared on the radiation performance. A flux density distribution measurement system for dish parabolic concentrators is developed. The contours of the flux distribution for target placements at different distances from the dish vertex of a solar concentrator are taken by using an indirect method with a Lambert and a charge coupled device (CCD) camera. Further, the measured flux distributions are compared with a Monte Carlo-predicted distribution. The results can be a valuable reference for the design and assemblage of the solar collector system.

关键词： Monte Carlo method solar energy radiation performance cavity receiver

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抛物形缓坡方程的数值研究

沈永明,郑永红,吴修广

《中国工程科学》 2004年第6卷第3期页码 30-35

摘要：

对2种典型的抛物形缓坡方程进行比较系统的数值研究。通过对4种典型地形上的波浪变形的数值模拟，详细讨论了网格节点数对数值解精度的影响、模型对初始入射角的敏感程度、非线性项对数值结果的影响等。研究结果可为实际应用抛物形缓坡方程研究大区域复杂地形上的波浪传播提供一定的理论指导。

关键词：抛物形缓坡方程数值研究波浪

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Effect of light scattering on the performance of a direct absorption solar collector

Kwang Hyun WON, Bong Jae LEE

《能源前沿（英文）》 2018年第12卷第1期页码 169-177 doi: 10.1007/s11708-018-0527-5

摘要： Recently, a solar thermal collector often employs nanoparticle suspension to absorb the solar radiation directly by a working fluid as well as to enhance its thermal performance. The collector efficiency of a direct absorption solar collector (DASC) is very sensitive to optical properties of the working fluid, such as absorption and scattering coefficients. Most of the existing studies have neglected particle scattering by assuming that the size of nanoparticle suspension is much smaller than the wavelength of solar radiation (i.e., Rayleigh scattering is applicable). If the nanoparticle suspension is made of metal, however, the scattering cross-section of metallic nanoparticles could be comparable to their absorption cross-section depending on the particle size, especially when the localized surface plasmon (LSP) is excited. Therefore, for the DASC utilizing a plasmonic nanofluid supporting the LSP, light scattering from metallic particle suspension must be taken into account in the thermal analysis. The present study investigates the scattering effect on the thermal performance of the DASC employing plasmonic nanofluid as a working fluid. In the analysis, the Monte Carlo method is employed to numerically solve the radiative transfer equation considering the volume scattering inside the nanofluid. It is found that the light scattering can improve the collector performance if the scattering coefficient of nanofluid is carefully engineered depending on its value of the absorption coefficient.

关键词： direct absorption solar collector plasmonic nanofluid light scattering

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Optical performance analysis of an innovative linear focus secondary trough solar concentrating system

Xiliang ZHANG, Zhiying CUI, Jianhan ZHANG, Fengwu BAI, Zhifeng WANG

《能源前沿（英文）》 2019年第13卷第3期页码 590-596 doi: 10.1007/s11708-018-0602-y

摘要： The parabolic trough solar concentrating system has been well developed and widely used in commercial solar thermal power plants. However, the conventional system has its drawbacks when connecting receiver tube parts and enhancing the concentration ratio. To overcome those inherent disadvantages, in this paper, an innovative concept of linear focus secondary trough concentrating system was proposed, which consists of a fixed parabolic trough concentrator, one or more heliostats, and a fixed tube receiver. The proposed system not only avoids the end loss and connection problem on the receiver during the tracking process but also opens up the possibility to increase the concentration ratio by enlarging aperture. The design scheme of the proposed system was elaborated in detail in this paper. Besides, the optical performance of the semi and the whole secondary solar trough concentrator was evaluated by using the ray tracing method. This innovative solar concentrating system shows a high application value as a solar energy experimental device.

关键词： secondary parabolic trough solar concentrator ray tracing method linear focus concentration ratio optical performance

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Characteristics and application of road absorbing solar energy

Zhihua ZHOU, Shan HU, Xiaoyan ZHANG, Jian ZUO

《能源前沿（英文）》 2013年第7卷第4期页码 525-534 doi: 10.1007/s11708-013-0278-2

摘要： If the heat of road surface can be stored in summer, the road surface temperature will be decreased to prevent permanent deformation of pavement. Besides, if the heat stored is released, it can supply heat for buildings or raise the road surface temperature for snow melting in winter. A road-solar energy system was built in this study, and the heat transfer mechanism and effect of the system were analyzed according to the monitored solar radiant heat, the solar energy absorbed by road and the heat stored by soil. The results showed that the road surface temperature was mainly affected by solar radiation, but the effect is hysteretic in nature. The temperature of the solar road surface was 3°C–6°C lower than that of the ordinary road surface. The temperature of the solar road along the vertical direction was 2°C–5°C lower than that of the ordinary road. The temperature difference increased as the distance to the heat transfer tubes decreased. The average solar collector efficiency of the system was 14.4%, and the average solar absorptivity of road surface was 36%.

关键词： solar energy road-solar energy system road surface temperature solar absorptivity of road surface solar collector efficiency of system

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近岸波浪破碎区污染物运动的数值模拟

唐军,沈永明,邱大洪

《中国工程科学》 2007年第9卷第12期页码 63-68

摘要：波浪斜向近岸传播中由波浪破碎作用所引起的近岸波流体系是近岸非常重要的环境水动力因素，对该区域污染物的运动分布起着重要的影响作用。结合近岸波浪传播的抛物型缓坡方程、近岸波流场数学模型及污染物在近岸波流作用下运动的数学模型，对近岸斜向入射波浪破碎所产生的沿岸波流场中污染物的分布运动过程进行了数值模拟，并结合实验结果对数值模拟结果进行了分析验证。

关键词：抛物型缓坡方程；波浪破碎区；辐射应力；沿岸流；污染物

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风云三号微波湿度仪天线设计与分析

王宏建,李靖,刘和光,张升伟

《中国工程科学》 2009年第11卷第4期页码 39-45

摘要：

风云三号（FY-3）湿度仪天线接收各种目标的微波辐射能量，因此天线好坏对整个微波湿度仪系统性能及应用影响极大。FY-3湿度仪天线具有高增益、低噪声和高的波束效率，采用偏馈抛物面天线形式，天线频率分别达到150 GHz和183 GHz，是目前国内有效载荷的最高频率，其成功研制填补了我国航天微波遥感的空白，也使我国航天器天线技术进入一个新的领域、实现了一次较大的技术跨越。文章从天线的系统工作模式、组成、设计要点、关键技术及验证等方面阐述该天线子系统的技术设计与创新。

关键词： FY-3湿度仪偏馈抛物面天线波纹喇叭遥感

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主支式排烟道中主烟道横截面尺寸的确定

黄锐,杨立中,范维澄

《中国工程科学》 2001年第3卷第11期页码 45-48

摘要：

高层住宅主支式排烟道的主烟道中烟气流动可看作是一维定常垂直摩擦管流。通过计算管流流动相与颗粒相的物理参数沿管程分布情况，确定了颗粒相流动情况，进而判断烟气排放情况。这受到排烟系统高度、烟道管径，及材料组成等因素的影响，通过预设排烟系统高度并保证良好排放情况，求得主烟道管径应满足的条件。这使得布设排烟道时可以找到一个较好的横截面尺寸，既满足烟气排放条件，又节约修建材料。

关键词：多相流主支式厨房排烟道计算模型