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The Design and Performance of a High Temperature Rise Combustor for Wind Tunnel

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Journal of Thermal Science 2011年第6期20卷 556-562页

作者： zhang rongchun fan weijun National Key Laboratory on Aero-Engines School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

A high-temperature-rise combustor that can be used in high-temperature wind tunnel is introduced in this *** kerosene is used in this type of combustor,with division combustion scheme and evaporator fuel-supply device *** the performance test under atmospheric pressure,when the inlet temperature is 500K and air flow is within the range of 1.5-3.0 kg/s,the outlet temperature can be precisely regulated within the range of ***,higher uniformity of outlet temperature distribution and higher combustion efficiency can be *** the long-time working in the wind tunnel,various components of the combustor,especially the combustor liners are checked without finding any anomaly such as thermal deformation.

关键词： high temperature rise evaporator wind tunnel combustor aviation kerosene

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一种一体化加力燃烧室的数值模拟

航空动力学报 2018年第2期33卷 470-476页

作者：尹成茗张荣春樊未军石强覃文隆北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室北京100191

为适应新一代航空发动机高推质比的设计要求,设计出一种一体化加力燃烧室方案,利用截尾支板与带凹腔的分流环组合结构取代了传统火焰稳定器。对该方案进行了数值模拟研究及试验验证,结果表明:在该一体化加力燃烧室内涵中有3个低速回流区... 详细信息

为适应新一代航空发动机高推质比的设计要求,设计出一种一体化加力燃烧室方案,利用截尾支板与带凹腔的分流环组合结构取代了传统火焰稳定器。对该方案进行了数值模拟研究及试验验证,结果表明:在该一体化加力燃烧室内涵中有3个低速回流区;截尾支板结构不仅起整流支板的作用,还能够起到火焰稳定器的作用;燃烧效率在90%~93%之间,流阻系数约为0.26;在所研究的工况下总压恢复系数均高于0.975,且主要的总压损失集中在截尾支板及分流环凹腔处。

关键词：加力燃烧室一体化火焰稳定器截尾支板凹腔

Experimental study of entrainment phenomenon in a trapped vortex combustor

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Chinese Journal of Aeronautics 2013年第1期26卷 63-73页

作者： zhang rongchun fan weijun National Key Laboratory of Science and Technology on Aero-Engines Aero-Thermodynamics School of Energy and Power Engineering Beihang University

Trapped vortex combustor （TVC） is an advanced low-pollution gas turbine combustor, with the adoption of staged combustion technique. To achieve low-pollutant emission and better combustion performance, the proportion of the air flow in each combustion zone should be precisely determined in the design of the combustor. Due to the presence of entrainment phenomenon, the total air flow in the cavity zone is difficult to estimate. To overcome the measurement difficulty, this study adopts the indirect measurement approach in the experimental research of entrainment phenomenon in the cavity. In accordance with the measurement principle, a TVC model fueled by methane is designed. Under two experimental conditions, i.e. with and without direct air intake in the cavity, the influence of the mainstream air flow velocity, the air intake velocity in the cavity, the height of inlet channel, the structure of holder and the structural proportion of the cavity on entrainment in the cavity is studied, respectively, through experiment at atmospheric temperature and pressure. The results suggest that the air flow velocity of mainstream, the air intake velocity of the cavity and the structure of the holder exert significant influence on the air entrainment, while the influence of structural proportion of the cavity is comparatively insignificant. The square root of momentum ratio of cavity air to mainstream air could be used to analyze the correlation of the entrainment data.

关键词： Combustion Entrainment Experiment Methane Trapped vortex combustor

Investigation on Atomization Performance of a Slinger

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Journal of Harbin Institute of Technology(New Series) 2021年第6期28卷 1-13页

作者： Wenlong Tan weijun fan Qiang Shi Hanqing Xu rongchun zhang School of Energy and Power Engineering Beihang UniversityBeijing 100191China

Slinger is a type of rotary atomizer wherein spray spatial distribution varies with the rotary speed and mass *** spray parameters at a series of locations in the radial direction of the slinger were measured and the parameters of the location where the spray Sauter Mean Diameter(SMD)corresponds to the smallest were selected to be *** results indicated that at a specific mass flowrate,an optimum diameter exists for the orifice,in which the orifice’s spray corresponds to the smallest and most *** in the mass flowrate increase the optimum ***,the spray from the circular orifice is more uniform compared with that from the slot orifice with the same *** the length of the orifice increases,the spray becomes larger but more *** liquid regime in the orifice affects primary atomization of the liquid,significantly affecting the spray SMD and uniformity.

关键词： slinger rotary atomization spray uniformity orifice

A novel(Sm_(0.2)Eu_(0.2)Gd_(0.2)Ho_(0.2)Yb_(0.2))CrO_(3)high-entropy ceramic nanofiber as a negative temperature coefficient thermistor

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Journal of Rare Earths 2024年第10期42卷 1937-1942页

作者： weijun Zhao Meng zhang Liyan Xue Kaixian Wang fan Yang Jiuping Zhong Heng Chen School of Materials Sun Yat-sen UniversityShenzhen518107China Xiamen Institute of Rare Earth Materials Haixi InstituteChinese Academy of SciencesXiamen361021China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen361021China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China Advanced Energy Science and Technology Guangdong Laboratory Huizhou516003China Sichuan Jcc Rare Earth Metals New Material Co. Ltd.Chengdu610000China

The electrical properties of high-entropy ceramics(HECs)have been extensively studied in recent years due to their unique structural characteristics and fascinating functional properties induced by entropy *** high-entropy(Sm_(0.2)Eu_(0.2)Gd_(0.2)Ho_(0.2)Yb_(0.2))CrO_(3)(HE-RECrO_(3))nanofibers were prepared by electro *** work demonstrates that HE-RECrO_(3)nanofibe rs were successfully synthesized at a low temperature(800℃),which is approximately 400℃lower than the temperatures at which chromate ceramics were synthesized via the sol-gel method and the solid-state reaction *** resistivity of HE-RECrO_(3)nanofibers decreases exponentially with increasing temperature from 25 to600℃.The logarithm of the resistivity is linearly related to the inverse of the temperature,confirming the negative temperature coefficient property of HE-RECrO_(3)*** B_(25/50)value of the HERECrO_(3)nanofibers reaches 4072 *** conclusion,HE-RECrO_(3)nanofibers are expected to be potential candidates for negative-temperature-coefficient(NTC)thermistors.

关键词： Rare earths High-entropy ceramics Ceramic fiber materials Negative temperature coefficient thermistors

The Distribution of Different Clades of Seneca Valley Viruses in Guangdong Province,China

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Virologica Sinica 2018年第5期33卷 394-401页

作者： Pan Chen fan Yang weijun Cao Huanan Liu Keshan zhang Xiangtao Liu Zhiwen Xu Zixiang Zhu Haixue Zheng State Key Laboratory of Veterinary Etiological Biology National Foot and Mouth Diseases Reference LaboratoryKey Laboratory of Animal Virology of Ministry of Agriculture Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences Animal Biotechnology Center Key Laboratory of Animal Disease and Human Health of Sichuan Province Sichuan Agricultural University

Seneca Valley virus (SVV), a newly determined etiological agent of vesicular disease in swine, causes porcine idiopathic disease and occasional acute death in piglets. Recently, an increased number of SVV infection cases have been reported in the United States (US) and China, resulting in significant economic losses to the swine industry. The first identification of SVV in China was reported in Guangdong Province, a major swine producing province. The cases of SVV were continuously reported in Guangdong in 2015 and 2016. However, the spread of SVV in Guangdong in 2017 remains *** this study, we determined two new SVV strains, CH-GD-2017-1 and CH-GD-2017-2, from Guangdong. The genetic analysis suggested that the two Guangdong strains showed different characteristics to previous Guangdong strains. They showed lower nucleotide similarity with strains isolated in 2015 and 2016, and were more similar to the US *** analyses indicated that the new strains were clustered in a different clade with previous Guangdong *** found 28 mutated amino acids in the new strains, compared with the first Guangdong strain, SVV CH-01-2015. In the geographic analysis, we found that the US and China reported more SVV cases than other countries, and most of the SVV cases were reported in east and central China—of which, Guangdong Province is one of the major epidemic regions. In conclusion, our findings indicate that SVV continued to spread in Guangdong Province in 2017, and two different clades of SVVs have emerged in this region.

关键词： Seneca Valley virus (SVV) Genomic sequence Phylogenetic tree Epidemiological analysis

FoxJ1 inhibits African swine fever virus replication and viral S273R protein decreases the expression of FoxJ1 to impair its antiviral effect

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Virologica Sinica 2022年第3期37卷 445-454页

作者： Caina Ma Shasha Li fan Yang weijun Cao Huisheng Liu Tao Feng Keshan zhang Zixiang Zhu Xiangtao Liu Yonghao Hu Haixue Zheng College of Veterinary Medicine Gansu Agricultural UniversityLanzhou730070China State Key Laboratory of Veterinary Etiological Biology National Foot and Mouth Diseases Reference LaboratoryKey Laboratory of Animal Virology of Ministry of AgricultureLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou730046China

African swine fever(ASF)is a highly pathogenic swine infectious disease that affects domestic pigs and wild boar,which is caused by the African swine fever virus(ASFV).ASF has caused huge economic losses to the pig industry and seriously threatens global food security and livestock *** date,there is no safe and effective commercial vaccine against *** the underlying mechanisms of ASFV-host interplay is critical for developing effective vaccines and drugs against *** the present study,RNA-sequencing,RT-qPCR and Western blotting analysis revealed that the transcriptional and protein levels of the host factor FoxJ1 were significantly down-regulated in primary porcine alveolar macrophages(PAMs)infected by ***-qPCR analysis showed that overexpression of FoxJ1 upregulated the transcription of type I interferon and interferon stimulating genes(ISGs)induced by poly(dA:dT).FoxJ1 revealed a function to positively regulate innate immune response,therefore,suppressing the replication of *** addition,Western blotting analysis indicated that FoxJ1 degraded ASFV MGF505-2R and E165R proteins through autophagy ***,RT-qPCR and Western blotting analysis showed that ASFV S273R inhibited the expression of ***,we determined that FoxJ1 plays an antiviral role against ASFV replication,and ASFV protein impairs FoxJ1-mediated antiviral effect by degradation of *** findings provide new insights into the antiviral function of FoxJ1,which might help design antiviral drugs or vaccines against ASFV infection.

关键词： African swine fever virus(ASFV) FoxJ1 ISGs MGF505-2R E165R S273R

Regulatory dynamics of the higher-plant PSI-LHCI supercomplex during state transitions

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Molecular Plant 2023年第12期16卷 1937-1950页

作者： Jianghao Wu Shuaijiabin Chen Chao Wang weijun Lin Chao Huang Chengxu fan Dexian Han Dandan Lu Xiumei Xu Senfang Sui Lixin zhang State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityJinming AvenueKaifeng 475004China School of Life Science Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Membrane Biology Beijing Advanced Innovation Center for Structural BiologyBeijing Frontier Research Center for Biological StructureSchool of Life SciencesTsinghua UniversityBeijing 100084China Cryo-EM Center Southern University of Science and TechnologyShenzhen 518055China Photosynthesis Research Center Key Laboratory of PhotobiologyInsttute of BotanyChinese Academy of SciencesBejing 100093China

State transition is a fundamental light acclimation mechanism of photosynthetic organisms in response to the environmental light *** process rebalances the excitation energy between photosystemI(PSl)and photosystem Il through regulated reversible binding of the light-harvesting complex Il(LHCll)to ***,the structural reorganization of PSI-LHCI,the dynamic binding of LHCll,and the regulatory mechanisms underlying state transitions are less understood in higher *** this study,using cryoelectron microscopy we resolved the structures of PSI-LHCI in both state 1(PSI-LHCI-ST1)and state 2(PSILHCI-LHCll-ST2)from Arabidopsis *** genetic and functional analyses revealed novel contacts between Lhcb1 and PsaK that further enhanced the binding of the LHCll trimer to the PSI core with the known interactions between phosphorylated Lhcb2 and the PsaL/PsaH/PsaO ***,PsaO was absent in the PSI-LHCI-ST1 supercomplex but present in the PSI-LHCI-LHCIl-ST2 supercomplex,in which the PsaL/PsaK/PsaA subunits undergo several conformational changes to strengthen the binding of PsaO in ***,the PSI-LHCI module adopts a more compact configuration with shorter Mg-to-Mg distances between the chlorophylls,which may enhance the energy transfer efficiency from the peripheral antenna to the PSl core in ***,our work provides novel structural and functional insights into the mechanisms of light acclimation during state transitions in higher plants.

关键词： state transitions dynamic conformation photosystem l regulatory mechanism Arabidopsis thaliana

Continuous measurement method and mathematical model for soil compactness

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International Journal of Agricultural and Biological Engineering 2022年第5期15卷 196-204页

作者： Huihui Zhao Tao Cui Li Yang Qingyan Hou weijun Yan Xiantao He Chenlong fan Jiaqi Dong Dongxing zhang College of Engineering China Agricultural UniversityBeijing 100083China The Soil-Machine-Plant Key Laboratory of the Ministry of Agriculture of China Beijing 100083China Shandong Guofeng Machinery Co. LtdJining 272000ShandongChina

With the continuous improvement of agricultural mechanization,soil compaction becomes more and more *** soil compaction has been considered as an important negative factor affecting crop growth and *** measurement of soil compactness is a common method to measure the soil compaction *** order to solve the problems of discontinuous sampling,time-consuming and poor real-time soil compactness measurement,a real-time measurement method of soil compactness based on fertilizing shovel was proposed,and the mathematical model between fertilizing shovel arm deformation and soil compactness was *** on the interaction mechanism between fertilizing shovel and soil,through the force analysis of fertilizing shovel,it was found that the deformation of fertilizing shovel arm was positively correlated with the sum of soil compactness(SSC)within the range of tillage *** order to verify the theoretical analysis results and the detection accuracy of strain gauge,the static bench test was carried *** test results showed that the strain gauge signal for measuring the deformation of the fertilizing shovel arm was significantly correlated with the applied *** fitting curve of the linear correlation coefficient was 0.999,the maximum detection error was 0.68 kg,and the detecting accuracy was within the tolerance of 0.57%.Through field orthogonal experiments with four working depths and four compaction levels,a mathematical model of the strain gauge signal and the SSC within the range of tillage depth was *** experiment showed that compared with the other three depths,the linear correlation coefficient at the tillage depth of 5 cm(TD5)was the lowest,and the slope of the fitting curve was obviously different from the other three depths,so the 5 cm data were excluded when *** model between mean signal value and mean SSC within the range of tillage depth was established based on the data of sampling points with tillage dept

关键词： soil compactness measurement fertilizing shovel strain gauge precision agriculture