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无热子空心阴极点火过程的放电维持失衡机理研究

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推进技术 2024年第8期45卷 257-267页

作者：苗鹏于博康小录王伟宗上海空间推进研究所上海201112 北京航空航天大学宇航学院北京100191

无热子空心阴极(HHC)的放电维持失衡是目前制约其工程应用的主要问题。为研究上述问题的核心机理,本文建立一种等离子体放电与固体传热耦合的非稳态数值模型,基于电子路径的网格划分方法,该模型可将放电过程和传热过程的时间步长同时设... 详细信息

无热子空心阴极(HHC)的放电维持失衡是目前制约其工程应用的主要问题。为研究上述问题的核心机理,本文建立一种等离子体放电与固体传热耦合的非稳态数值模型,基于电子路径的网格划分方法,该模型可将放电过程和传热过程的时间步长同时设定在1 ms量级,同时提升计算效率和精度。在真空舱内开展HHC的发射体测温与阳极电流诊断试验,以试验数据对数值模型进行验证和修正,修正后的模型计算误差为:发射体温度2.5%~8.4%;阳极电流5.6%~12.9%。在此基础上,通过数值模型针对HHC在不同工况下的点火过程进行数值模拟,发现HHC是否存在电子发射衰弱区是引起放电维持失衡的主要机制,而降低气体流率、降低触持极管-阴极管间隙距离以及增加阴极管材料的传热能力,是增加电子发射衰弱区存在可能性的因素。

关键词：电推进无热子空心阴极放电维持失衡放电与传热耦合模型非稳态数值模拟电子发射衰弱区

Effects of the critical breakdown path on the ignition performance in heaterless hollow cathodes

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Plasma Science and Technology 2020年第6期22卷 164-179页

作者： Bo YU Yanda LEE xiaolu kang Qing ZHAO Center for Information Geoscience School of Resources and EnvironmentUniversity of Electronic Science and Technology of ChinaChengdu 611731People's Republic of China Shanghai Institute of Space Propulsion Shanghai 201112People's Republic of China

The critical breakdown path(CBP)has a significant impact on the breakdown voltage curve and the ignition time of heaterless hollow cathodes(HHCs).To determine the pattern of the variation in the CBP position and its impact on ignition performance,a numerical model named the CBP evaluation(CBPE)was established in this paper to calculate the CBP of a *** CBPE model can be used to screen various potential breakdown paths to identify those that are most likely to satisfy the Townsend breakdown conditions,which are denoted as *** verify the calculation accuracy of the CBPE model,4.5 A-level HHC ignition tests were conducted on HHCs with three different *** comparing the test results and the calculated results of the breakdown voltage,the calculation errors of the CBPE under three HHC conditions ranged from 1.6%to 5.8%,and the trends of the calculated results were consistent with those of the test *** ignition test also showed the characteristics of the breakdown voltage curve and the ignition time for the three *** on the CBPE model,an in-depth analysis was conducted on the mechanism of the patterns revealed by the *** main conclusions are presented as follows:(1)the CBP always shifts from the long path to the short path in the HHCs with an increasing gas flow rate;and(2)the ignition time of the HHCs depends on the position of the CBP because different CBP positions can cause different mechanisms of heat transfer from the plasma to the *** study can guide the optimization of the CBP position and the corresponding ignition times of HHCs.

关键词： breakdown path heaterless hollow cathode breakdown voltage ignition time numerical calculation

Optical analysis method for fast plasma characterization of high-speed miniaturized synthetic jet

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Chinese Optics Letters 2022年第7期20卷 41-46页

作者： Ye Yuan Yan Zhang Cheng Guo xiaolu kang Zhong Yan Xiaoping Huang Qing Zhao School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 610054China Shanghai Institute of Space Propulsion Shanghai Engineering Research Center of Space EngineShanghai 201112China

In this paper,a new optical analysis method for plasma characterization is *** characteristics are obtained directly by measuring the plasma luminous color,rather than the complex spectral diagnosis method,which is difficult to obtain at high *** using the light transmittance curve of the human cornea,the RGB coordinates are calculated from the measured plasma spectrum *** characteristics are diagnosed using the Boltzmann plot method and the Stark broadening *** corresponding relationship of the electron temperature,electron density data points,and luminous color is established and *** research results indicate that this optical analysis method is feasible and promising for fast plasma characterization.

关键词： optical analysis method plasma characteristics spectral diagnosis high-speed miniaturized actuator

Evaluation and projection of marine heatwaves in the South China Sea: insights from CMIP6 multi-model ensemble

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Acta Oceanologica Sinica 2024年第7期43卷 15-25页

作者： Kai Liu kang Xu Tongxin Han Congwen Zhu Nina Li Anboyu Guo xiaolu Huang National Marine Environmental Forecasting Center Beijing 100081China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China National Meteorological Center China Meteorological AdministrationBeijing 100081China Inner Mongolia Autonomous Region Meteorological Observatory Huhhot 010051China

This study evaluates the performance of 16 models sourced from the coupled model intercomparison project phase 6(CMIP6)in simulating marine heatwaves(MHWs)in the South China Sea(SCS)during the historical period(1982−2014),and also investigates future changes in SCS MHWs based on simulations from three shared socioeconomic pathway(SSP)scenarios(SSP126,SSP245,and SSP585)using CMIP6 *** demonstrate that the CMIP6 models perform well in simulating the spatial-temporal distribution and intensity of SCS MHWs,with their multi-model ensemble(MME)results showing the best *** reasonable agreement between the observations and CMIP6 MME reveals that the increasing trends of SCS MHWs are attributed to the warming sea surface temperature *** various SSP scenarios,the year 2040 emerges as pivotal juncture for future shifts in SCS MHWs,marked by distinct variations in changing rate and *** is characterized by an accelerated decrease in MHWs frequency and a notably heightened increase in mean intensity,duration,and total days after ***,the projection results for SCS MHWs suggest that the spatial pattern of MHWs remains consistent across future ***,the intensity shows higher consistency only during the near-term period(2021−2050),while notable inconsistencies are observed during the medium-term(2041−2070)and long-term(2071−2100)periods under the three SSP *** the nearterm period,the SCS MHWs are characterized by moderate and strong events with high frequencies and relatively shorter *** contrast,during the medium-term period,MHWs are also characterized by moderate and strong events,but with longer-lasting and more intense events under the SSP245 and SSP585 ***,in the long-term period,extreme MHWs become the dominant feature under the SSP585 scenario,indicating a substantial intensification of SCS MHWs,effectively establishing a near-permanent state.

关键词： marine heatwaves South China Sea global warming future projections CMIP6

Evaluation and projection of marine heatwaves in the South China Sea:insights from CMIP6 multi-model ensemble

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Acta Oceanologica Sinica 2024年第7期 15-25页

作者： Kai Liu kang Xu Tongxin Han Congwen Zhu Nina Li Anboyu Guo xiaolu Huang National Marine Environmental Forecasting Center State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences National Meteorological Center China Meteorological Administration Inner Mongolia Autonomous Region Meteorological Observatory

This study evaluates the performance of 16 models sourced from the coupled model intercomparison project phase 6(CMIP6) in simulating marine heatwaves(MHWs) in the South China Sea(SCS) during the historical period(1982-2014), and also investigates future changes in SCS MHWs based on simulations from three shared socioeconomic pathway(SSP) scenarios(SSP126, SSP245, and SSP585) using CMIP6 models. Results demonstrate that the CMIP6 models perform well in simulating the spatial-temporal distribution and intensity of SCS MHWs,with their multi-model ensemble(MME) results showing the best performance. The reasonable agreement between the observations and CMIP6 MME reveals that the increasing trends of SCS MHWs are attributed to the warming sea surface temperature trend. Under various SSP scenarios, the year 2040 emerges as pivotal juncture for future shifts in SCS MHWs, marked by distinct variations in changing rate and amplitudes. This is characterized by an accelerated decrease in MHWs frequency and a notably heightened increase in mean intensity, duration, and total days after 2040. Furthermore, the projection results for SCS MHWs suggest that the spatial pattern of MHWs remains consistent across future periods. However, the intensity shows higher consistency only during the near-term period(2021-2050), while notable inconsistencies are observed during the medium-term(2041-2070) and long-term(2071-2100) periods under the three SSP scenarios. During the nearterm period, the SCS MHWs are characterized by moderate and strong events with high frequencies and relatively shorter durations. In contrast, during the medium-term period, MHWs are also characterized by moderate and strong events, but with longer-lasting and more intense events under the SSP245 and SSP585 scenarios. However,in the long-term period, extreme MHWs become the dominant feature under the SSP585 scenario, indicating a substantial intensification of SCS MHWs, effectively establishing a near-permanent state

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霍尔推力器羽流对S波段电磁波的衰减研究

中国空间科学技术 2019年第5期39卷 19-27页

作者：于博张敏余水淋康小录电子科技大学信息地学研究中心成都611731 上海空间推进研究所上海201112 上海空间发动机工程技术研究中心上海201112

霍尔推力器羽流对S波段电磁波信号有衰减作用,这对星上推力器与天线的布置策略有重要影响。为研究S波段电磁波的衰减程度,建立几何光路算法,对电磁波在等离子体羽流媒质中的传输衰减进行数值描述,并以试验所测的信噪比数据来验证算法精... 详细信息

霍尔推力器羽流对S波段电磁波信号有衰减作用,这对星上推力器与天线的布置策略有重要影响。为研究S波段电磁波的衰减程度,建立几何光路算法,对电磁波在等离子体羽流媒质中的传输衰减进行数值描述,并以试验所测的信噪比数据来验证算法精度。验证试验采用空间透射波法,在相同工况的试验与计算结果对比中,最大计算误差为26.1%,平均误差为7.3%;在趋势上,试验结果与计算结果保持一致。在此基础上,针对84个在轨典型工况进行S波段电磁波信噪比衰减计算,结果显示:羽流对电磁波的吸收作用是影响衰减的主要因素,衰减最大区域出现在天线位置0.3~0.6 m、方向角15°~30°的区域,衰减值在-7^-4 dB之间。该结果可为霍尔推力器与天线在卫星的布置提供参考依据。

关键词：霍尔推力器羽流几何光路 S波段电磁波衰减电推进

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霍尔推力器羽流对太阳翼的溅射影响规律

中国空间科学技术 2018年第5期38卷 7-16页

作者：于博王宣余水淋康小录上海空间推进研究所上海201112 电子科技大学电子学院成都611731 上海空间发动机工程技术研究中心上海201112

霍尔推力器羽流对太阳翼的溅射作用是影响翼板工作性能、卫星供能稳定性的重要因素。为深入研究霍尔推力器羽流在不同布置工况下对太阳翼的溅射影响规律,采用单元粒子/直接蒙特卡洛碰撞模型(PIC/DSMC)求解羽流等离子体的输运过程,其中... 详细信息

霍尔推力器羽流对太阳翼的溅射作用是影响翼板工作性能、卫星供能稳定性的重要因素。为深入研究霍尔推力器羽流在不同布置工况下对太阳翼的溅射影响规律,采用单元粒子/直接蒙特卡洛碰撞模型(PIC/DSMC)求解羽流等离子体的输运过程,其中对离子的扩散作用采用基于菲克定律的求解模型,并以Yamamura溅射模型来求解等离子体对太阳翼表面的溅射产额。为验证修正扩散模型后的算法精度,在真空舱内开展羽流诊断试验,以试验与计算结果的对比来修正扩散经验参数以及验证计算精度。试验结果表明,在扩散系数kd=1.26×10-36 N·m4时,该模型计算误差在8.7%左右。在此基础上,对不同的推力器方位角、推力器与翼板距离工况,开展羽流对太阳翼的溅射产额计算。计算结果给出太阳翼表面溅射分布随方位角、距离增加的依变规律,并进行了相关透光率影响程度的讨论,可对推力器的星上布置提供参考依据。

关键词：霍尔推力器羽流溅射太阳翼数值计算

Study on High Power Hall Electric Propulsion Technology

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Aerospace China 2020年第2期21卷 31-38页

作者： HANG Guanrong ZHAO Zhen YU Shuilin QIAO Caixia LIU Jia HUANG Hao TIAN Leichao LI Lin LI Wenshuai kang xiaolu Shanghai Institute of Space Propulsion Shanghai 201112 Shanghai Engineering Research Center of Space Engine Shanghai 201112

High power Hall electric propulsion technology is a very competitive electric propulsion technology for future large space missions such as large GEO satellites,manned space programs,deep space explorations,cargo ships,space *** on the experience of more than 20 years in research and development of Hall electric propulsion,the Shanghai Institute of Space Propulsion(SISP)has developed 3 high power Hall thrusters,i.e.,the 10 k W class HET-500,20 k W class HET-1000,and 50 k W class *** paper presents the development status of the high power(≥10 k W)Hall electric propulsion at SISP,including tests of 3 high power Hall thrusters in the power range from 10 k W to 50 k W,the qualification of a single string of a 10 k W Hall electric propulsion system,and the study of a cluster of two 1.35 k W HET-80 Hall thrusters to understand the technical issues related to multi-thruster high power electric propulsion systems.

关键词： high power Hall electric propulsion Hall thruster single string system integration thruster cluster

探析移动端展览应用的传播实践——以故宫博物院“故宫展览”数字化项目为例

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自然科学博物馆研究 2022年第2期 20-31,92页

作者：康晓璐故宫博物院 100009

通过移动端推送博物馆展览是博物馆信息化的重要内容,但不少博物馆面临数字化应用无法实现服务质量和用户体验的预期,导致下载量和使用量较低的处境。本文以“故宫展览”数字化项目为例,通过对开发数字产品观念意识、展示设计能力的分析... 详细信息

通过移动端推送博物馆展览是博物馆信息化的重要内容,但不少博物馆面临数字化应用无法实现服务质量和用户体验的预期,导致下载量和使用量较低的处境。本文以“故宫展览”数字化项目为例,通过对开发数字产品观念意识、展示设计能力的分析,总结出在设计数字产品中结合博物馆需求与观众需求,结合观众心理习惯与博物馆特色,构建以“物”为核心的展示内容,兼顾知识性与趣味性的展示形式,应用分众化传播策略等方法,探讨借助移动端数字应用对博物馆以教育为目标的传播属性起到的积极作用。

关键词：博物馆媒介技术移动端应用传播 “故宫展览”APP