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Numerical analysis on combustion characteristics of hybrid rocket motor with star-tube segmented grain

Chinese Journal of Aeronautics 2023年第12期36卷 102-112页

作者： Chengen LI Zongwei WANG Jin YANG Jinpeng JIANG Fan GONG Zhu LIU Yu SUN Science and Technology on Space Physics Laboratory Beijing 100076China

A method of star-tube combined segmented grain is proposed to improve the combustion performance of hybrid rocket *** star-tube combined segmented grain consists of a single-port star part and a single-port tube part.A mid-chamber forms between the fore-grain and the aft-grain for better mixing *** single-port feature gives hybrid rocket motor several advantages,such as simple structure,high reliability,and variable *** paper is mainly aimed at studying the combustion characteristics of hybrid rocket motor with star-tube segmented grain through three-dimensional steady *** performance of the motors with different segmented grain combinations,including fore-tube/aft-tube,fore-tube/aftstar,fore-star/aft-star and fore-star/aft-tube,is contrastively *** motor in this paper adopts polyethylene and 90%hydrogen peroxide as the *** reveal that segmented grain with different-type grain combinations could greatly change the flow field in the second half of the combustion *** of the flow field is beneficial to the mixing between the fuel and the oxidizer,and it could increase the fuel regression rate and the combustion *** turbulence effect of tube aft-grain is better than that of star *** the four segmented grain combinations,the combination of star fore-grain and tube aft-grain is the preferred method with optimal overall *** grain configuration could increase the regression rate of tube aft-grain to surpass that of star aft-grain in other ***,hybrid rocket motor with this grain configuration achieves the highest combustion efficiency.

关键词： Combustion performance Flow fields Fluid-solid coulping Hybrid rocket motor Star-tube segmented grain

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Secondary electron yield of air-exposed ALD-Al_(2)O_(3) coating on Ag-plated aluminum alloy

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Chinese physics B 2024年第11期33卷 265-271页

作者： Xue-Man Wan Tian-Cun Hu Jing Yang Na Zhang Yun He Wan-Zhao Cui National Key Laboratory of Science and Technology on Space Microwave China Academy of Space Technology (Xi'an)Xi'an 710100China

Secondary electron yield(SEY)of air-exposed metals tends to be increased because of air-formed oxide,hydrocarbon,and other *** enhances the possibility of secondary electron multipacting in high-power microwave systems,resulting in undesirable occurrence of discharge ***_(2)O_(3) coatings have been utilized as passive and protective layers on device packages to provide good environmental *** employed atomic layer deposition(ALD)to produce a series of uniform Al_(2)O_(3) coatings with appropriate thickness on Ag-plated aluminum *** secondary electron emission characteristics and their variations during air exposure were *** escape depth of secondary electron needs to exceed the coating thickness to some extent in order to demonstrate SEY of metallic *** on experimental and calculated results,the maximum SEY of Ag-plated aluminum alloy had been maintained at 2.45 over 90 days of exposure without obvious degradation by applying 1 nm Al_(2)O_(3) *** comparison,the peak SEY of untreated Ag-plated aluminum alloy grew from an initial 2.33 to 2.53,exceeding that of the 1 nm Al_(2)O_(3) *** ultra-thin ALDAl_(2)O_(3) coating substantially enhanced the SEY stability of metal materials,with good implications for the environmental dependability of spacecraft microwave components.

关键词： secondary electron yield(SEY) atomic layer deposition air exposure multipactor

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Simulations of electron zebra stripes in the inner radiation belt using a composite empirical electric field model

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science China Earth sciences 2025年第1期68卷 27-38页

作者： Ziyang WANG Ying LIU Qiugang ZONG Hong ZOU Yuguang YE Xuzhi ZHOU Chao YUE Shan WANG Institute of Space Physics and Applied Technology Peking UniversityBeijing100871China State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyMacao999078China

The phenomenon termed“zebra stripes”manifests as regular patterns in the energy-space(L shell)spectrum of energetic electrons(ranging from tens to hundreds ke V)within the inner radiation *** structures exhibit drift-periodic behavior and commonly arise from large-scale electric field perturbations near the substorm *** this study,we introduce a composite electric field model and replicate the formation,structure,and evolution of zebra stripes using a bounce-averaged test particle code under this electric field ***-resolution measurements of energetic electrons obtained from the Van Allen Probes and the recently launched Macao science Satellites-1 are used as initial conditions and served to validate our test particle *** analyses between observed data and simulations demonstrate our test particle method's efficacy in capturing zebra stripes'general ***,the composite model proves capable of reproducing realistic variations in the electric field within the inner radiation belt to a certain ***,subtle differences emerge in the flux strength and the positions of *** disparities primarily stem from limitations inherent in the electric field model and the initial conditions of the *** that the model represents an average case,it is conceivable that real-world scenarios may deviate from the average,thereby introducing variations in the observed phenomena.

关键词： Zebra stripes Inner radiation belt Large-scale electric fields Van Allen Probes Macao science Satellite

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Evolution of electron“zebra stripes”in the South Atlantic Anomaly:Initial observations from Macao science Satellite-1

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science China(Technological sciences) 2024年第11期67卷 3344-3353页

作者： LIU Ying ZONG QiuGang ZOU Hong YE YuGuang SUN YiXin Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyMacao 999078China

“Zebra stripes”denote banded structures characterized by periodic peaks and valleys in the spectrograms of energetic electrons in the Earth's inner radiation belt and slot *** contrast to previous investigations primarily grounded in equatorial observations,this study presents two events exhibiting the evolution of electron zebra stripes within the South Atlantic Anomaly,as observed from the Macao Scientific Satellite-1 in low Earth *** findings affirm that the structural and evolutionary features of zebra stripes in both events accord with the drift echo *** start time extrapolated from the electron spectrograms correlates with substorm onsets,consistent with prior ***,the duration of zebra stripe evolution during the event of June 5–6,2023,reaches an impressive 34.7 h,a markedly longer interval than findings from the Van Allen *** discrepancy suggests that the observed lifetime of electron zebra stripes may not inherently reflect natural limitations but could be constrained by instrumental *** results implicate that high-energy-resolution detectors have the potential to significantly enhance our capacity to scrutinize the dynamics of the radiation belt.

关键词： zebra stripe inner radiation belt energetic electron South Atlantic Anomaly Macao science Satellite large-scale electric field

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Calibration of the Solar X-ray Detector on-board the Macao science Satellite-1B for Soft X-ray Detection

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science China Earth sciences 2025年第1期68卷 11-26页

作者： Man-Hei NG Xiaoping ZHANG Jianwu CHEN Yongqiang SHI Fuchang ZUO Wenxi PENG Weichun FU Liansheng LI Pengwei LUO Chi-Long TANG Guozheng ZHANG Zhiwu MEI Li WANG Cunhui LI Jiaming OU Yanyan Xu State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao999078China Space Optoelectronic Measurement and Perception Laboratory Beijing Institute of Control EngineeringBeijing100190China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsLanzhou730000China China National Space Administration(CNSA) Macao Center for Space Exploration and ScienceMacao999078China

The Solar X-ray Detector(SXD)on-board the Macao science Satellite-1B(MSS-1B)was successfully launched via the Chinese Long March-2C rocket on 21 May 2023,and commenced operations in early June of the same *** MSS-1B/Soft X-ray Detection Units(SXDUs)employ two silicon drift detectors(SDDs),providing a wide range of energy spectra spanning from 0.7 to 24 ***,the SXDUs deliver a high-resolution capability of 0.14 keV@5.9 keV and operate with a time cadence of 1 ***,we perform thorough calibrations of the MSS-1B/SXDUs,employing a combination of ground experiments and *** addition,quantitative analysis comparing the flux measurements obtained by the MSS-1B/SXDUs to the data collected by the Geostationary Operational Environmental Satellite(GOES),provides compelling evidence of their ***,the preliminary spectral analysis results showcase the robustness and expected performance of the MSS-1B/SXDUs,unlocking their potential for facilitating the study of dynamic evolution of solar ***,the innovative MSS-1B/Solar X-ray Detector facilitates concurrent observations of solar soft and hard X-rays,thereby making valuable contributions to the advancements in solar research.

关键词： Macao science Satellite-1B(MSS-1B) Calibration Solar X-Ray Detector Spectrometer Soft X-rays Solar flares Solar abundances

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Weak-measurement-based pseudospin pointer: A cost-effective scheme for precision measurement

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Physical Review A 2024年第6期109卷 L060601-L060601页

作者： Ling Ye Lan Luo An Wang Rongchun Ge Zhiyou Zhang College of Physics Key Laboratory of Science and Technology on Space Optoelectronic Precision Measurement CAS Chengdu 610209 China

As an essential component of state-of-the-art quantum technologies, fast and efficient quantum measurements are in persistent demand over time. Here, we present a precision measurement scheme for weak signals. We propose a dimensionless pseudo-spin pointer based on weak measurement which effectively converts a continuous measurement into a discrete one. We demonstrate experimentally that a weak perturbation of the parametric distribution's moment can be retrieved efficiently by employing the pointer without measuring the distribution literally. The results show that for signals three to four orders weaker in strength than the area-array camera method, an order of improvement in precision is achieved experimentally. We expect that this method can be effectively loaded into various quantum systems and promote the development of quantum precision measurement or quantum computing.

关键词： Photonics Quantum measurements Quantum optics Quantum parameter estimation Quantum sensing Laser systems Photon counting Weak measurements

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Scanning tunneling microscopy study on symmetry breaking of charge density wave in FeGe

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Chinese physics B 2025年第4期34卷 55-61页

作者： Jiakang Zhang Ziyuan Chen Xueliang Wu Mingzhe Li Yuanji Li Ruotong Yin Jiashuo Gong Shiyuan Wang Aifeng Wang Dong-Lai Feng Ya-Jun Yan School of Emerging Technology and Department of Physics University of Science and Technology of ChinaHefei 230026China Low temperature Physics Laboratory College of Physics and Center of Quantum Materials and DevicesChongqing UniversityChongqing 401331China National Synchrotron Radiation Laboratory and School of Nuclear Science and Technology New Cornerstone Science LaboratoryUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230026China

The complex symmetry breaking states in AV3Sb5 family have attracted extreme research attention,but controversy still exists,especially in the question of time reversal symmetry breaking of the charge density wave(CDW).Most recently,a chiral CDW has been suggested in kagome magnet FeGe,but the related study is very ***,we use a scanning tunneling microscope to study the symmetry breaking behavior of both the short-and long-range CDWs in *** from previous studies,our study reveals an isotropic long-range CDW without obvious symmetry breaking,while local rotational symmetry breaking appears in the short-range CDW,which may be related to the existence of strong structural ***,the charge distribution of the short-range CDW is inert to the applied external magnetic fields and the detailed spin arrangements of FeGe,inconsistent with the expectation of a chiral CDW associated with chiral *** results rule out the existence of spontaneous chiral and rotational symmetry breaking in the CDW state of FeGe,putting strong constraints on the further understanding of CDW mechanism.

关键词： symmetry breaking kagome magnet charge density wave

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Comprehensive analysis of noise in Macao science Satellite-1 vector magnetometer data

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Earth and Planetary physics 2025年第3期9卷 532-540页

作者： SiShan Song Fan Yin Qin Yan Hermann Lühr Chao Xiong Yi Jiang PengFei Liu Department of Space Physics School of Earth and Space Science and TechnologyHubei Luojia LaboratoryWuhan UniversityWuhan 430072China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China Macao Institute of Space Technology and Application Macao University of Science and TechnologyMacao 999078China GFZ Helmholtz Centre for Geosciences Section 2.3 GeomagnetismPotsdamGermany

The Macao science Satellite-1(known as MSS-1)is the first scientific exploration satellite that was designed to measure the Earth's low latitude magnetic field at high resolution and with high precision by collecting data in a near-equatorial *** field data from MSS-1's onboard Vector Fluxgate Magnetometer(VFM),collected at a sample rate of 50 Hz,allows us to detect and investigate sources of magnetic data contamination,from DC to relevant Nyquist *** we report two types of artificial disturbances in the VFM *** is V-shaped events concentrated at night,with frequencies sweeping from the Nyquist frequency down to zero and back *** other is 5-Hz events(ones that exhibit a distinct 5 Hz spectrum peak);these events are always accompanied by intervals of spiky signals,and are clearly related to the attitude control of the *** analyses show that VFM noise levels in daytime are systematically lower than in *** daily average noise levels exhibit a period of about 52 *** V-shaped events are strongly correlated with higher VFM noise levels.

关键词： Macao science Satellite-1 Vector Fluxgate Magnetometer artificial disturbances noise features

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Coexisting lattice contractions and expansions with decreasing thicknesses of Cu(100)nano-films

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Chinese physics B 2023年第3期32卷 408-413页

作者：安思敏高兴誉张弦陈欣咸家伟刘瑜孙博刘海风宋海峰 Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China

Lattice parameters are a basic quantity in material characterization,and a slight alteration in lattice parameters directly affects the properties of ***,there are still considerable controversies as to whether lattice expansion or contraction occurs in metallic nanomaterials with size ***,the size dependences of the lattice parameter and surface free energy of clean Cu(100)films are investigated via *** parameters of the exposed surfaces contract,whereas lattice expansion occurs along the direction perpendicular to the surfaces with decreasing film *** is striking since the metallic bonds usually lack strong directionality,and it is always regarded that the lattice variations in all directions are *** contraction parallel to the surface is more severe than the expansion perpendicular to the surface in *** lattices change from cubic to tetragonal with decreasing film ***,common contractions and occasional expansions of the lattice parameters of Cu nanoparticles have been observed in previous *** free energy and surface free energy with decreasing thicknesses is the thermodynamic origin of the lattice *** study therefore provides a comprehensive physical basis for the surface effects on the lattice variations.

关键词： nanostructure lattice variations surface free energy simulation

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Electronic effects on radiation damage inα-iron:A molecular dynamics study

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Chinese physics B 2024年第3期33卷 521-529页

作者：江林李敏付宝勤崔节超侯氢 Key Laboratory for Radiation Physics and Technology Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China

Iron(Fe)-based alloys,which have been widely used as structural materials in nuclear reactors,can significantly change their microstructure properties and macroscopic properties under high flux neutron irradiation during operation,thus,the problems associated with the safe operation of nuclear reactors have been put forward *** this work,a molecular dynamics simulation approach combined with electronic effects is developed for investigating the primary radiation damage process inα-***,the influence of electronic effects on the collision cascade in Fe is systematically evaluated based on two commonly used interatomic potentials for *** simulation results reveal that both electronic stopping(ES)and electron-phonon coupling(EPC)can contribute to the decrease of the number of defects in the thermal spike *** application of ES reduces the number of residual defects after the cascade evolution,whereas EPC has a reverse *** introduction of electronic effects promotes the formation of the dispersive subcascade:ES significantly changes the geometry of the damaged region in the thermal spike phase,whereas EPC mainly reduces the extent of the damaged ***,the incorporation of electronic effects effectively mitigates discrepancies in simulation outcomes when using different interatomic potentials.

关键词： radiation damage electronic effects molecular dynamics simulation α-iron

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