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Prediction of Equivalent Thermal Conduction Resistance of Printed Circuit Heat Exchangers

Journal of Thermal Science 2022年第6期31卷 2281-2292页

作者： SHI Haoning CHANG hongliang MA Ting WANG Qiuwang Key Laboratory of Thermo-Fluid Science and Engineering MOEXi’an Jiaotong UniversityXi'an 710049China

Printed circuit heat exchangers(PCHEs) have great potential to be employed in the advanced nuclear reactor systems. In this work, the equivalent thermal conduction resistance of PCHE is studied. The influences of thermal convection resistance are analyzed. The results indicate that the equivalent thermal conduction resistance of PCHEs with unequal numbers of hot plates and cold plates are sensitive to the thermal convection resistance of hot side and cold side. Specifically, for case C which has unequal number of hot and cold channels, the maximum value of equivalent thermal conduction resistance can be 1.7-2.4 times the minimum value. The equivalent thermal conduction resistance is underestimated under the isothermal boundary. In addition, the non-uniformity of the lengths of all the heat flux lines determines the influence degree of thermal convection resistance on the equivalent thermal conduction resistance. For further investigation, Latin hypercube sampling method is adopted to generate a large number of design points for each PCHE configuration. Based on the sample data, mathematical correlations and artificial neural network(ANN) for prediction of equivalent thermal conduction resistance for each case are developed. The proposed correlations of equivalent thermal conduction resistance for each case have acceptable accuracy of prediction with a wide range covering general engineering applications. The ANN model can achieve much better prediction accuracy than the proposed correlations thus it is recommended in the cases that the prediction accuracy is considered as the priority need.

关键词： equivalent thermal conduction resistance printed circuit heat exchanger numerical calculation correlations artificial neural network

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Lacustrine record of 800 yr hydrological variations on the central Tibetan Plateau

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Frontiers of Earth Science 2023年第4期17卷 945-955页

作者： hongliang ZHANG Hucai ZHANG Yanbin LEI School of Resources Environment and Tourism Anyang Normal UniversityAnyang 455002China School of Ecology and Environmental Science Yunnan UniversityKunming 650500China State Key Laboratory of Tibetan Plateau Earth System Environment and ResourcesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Zige Tangco is a meromictic saline lake located on the central Tibetan *** parallel cores(ZGTC A-1 and ZGTC A-2)were collected from the lake at a water depth of 25 m during summer *** chronology of core A-1 was reconstructed based on the Constant Initial Concentration(CIC)model of 210Pb and three accelerator mass spectrometry(AMS)ages from the chitin *** hard water effect calibration of the sediment ^(14)C age showed that the reservoir effect ranged from 1655 yr at 1950 AD to 1540 yr at 1610 *** hydrological variation in Zige Tangco during the past 800 yr was reconstructed using multi-proxies,including organic and carbonate content,stable isotopes of fine-grained carbonate minerals(<38.5μm)and grain-size distribution of the lake *** results show that there were strong fluctuations in the lake level between 1200 and 1820 AD,and at least three dry periods were recorded between 1235 and 1315 AD,1410 and 1580 AD,and 1660 and 1720 AD characterized by high carbonate content,abrupt positive shifts of stable isotopes,and high sand *** low-lake-level periods during the Little Ice Age(LIA)in Zige Tangco correspond to the lower δ^(18)O values in the Guliya ice core and the lower precipitation reconstructed from tree rings in *** demonstrated that the summer monsoon on the central Tibetan Plateau weakened during the dry and cold periods,whereas the winter monsoon *** wetter periods or higher lake levels in Zige Tangco occurred at 1580-1650 AD and 1820-1900 *** shifts in stable isotopes were related to increased lake levels between 1800 and 1820 *** results also showed that the summer monsoon precipitation on the central Tibetan Plateau was mainly controlled by solar activity during the past 800 yr.

关键词： hydrological variation Zige Tangco stable isotopes central Tibetan Plateau lacustrine sediments LIA

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A Novel Hydrothermal Synthesis of Single Crystalline PbS Nanorods and Their Characterization

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Journal of Materials Science & Technology 2005年第5期21卷 609-612页

作者： hongliang ZHU Deren YANG Hui ZHANG center of Materials Engineering Zhejiang Sci-Tech University Hangzhou 310018 China State Key Lab of Silicon Materials Zhejiang University Hangzhou 310027 China

Lead sulfide （PbS） nanorods with a high aspect ratio were prepared by a novel thioglycolic acid assisted hydrothermal method. X-ray diffraction and transmission electron microscopy revealed that the product was rod-like PbS with cubic rock-salt structure. Further characterizations by selected area electron diffraction and high-resolution transmission electron microscopy showed that the PbS nanorods were single crystalline in nature. Furthermore, the mechanism and critical factors for the hydrothermal synthesis of the nanorods have been discussed.

关键词： Lead sulfide Nanostructures Hydrothermal method

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Parameter identifications for a rotor system based on its finite element model and with varying speeds

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Acta Mechanica Sinica 2010年第2期26卷 299-303页

作者： Qingkai Han hongliang Yao Bangchun Wen School of Mechanical Engineering and Automation Northeastern University 110004 Shenyang China

In order to achieve prediction for vibration of rotating machinery, an accurate finite element （FE） model and an efficient parameter identification method of the rotor system are required. In this research, a test rig is used as a prototype of a rotor system to validate a novel parameter identification technique based on an FE model. Rotor shaft vibration at varying operating speeds is measured and correlated with the FE results. Firstly, the theories of the FE modelling and identification technique are introduced. Then disk unbalance parameter, stiffness and damping coefficients of the bearing supports on the test rig are identified. The calculated responses of the FE model with identified parameters are studied in comparison with the experimental results.

关键词： Rotor system · Finite element model ·Parameter identification· Model validation

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Analysis on Nonlinear Dynamic Properties of Dual-Rotor System

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Journal of Harbin Institute of Technology(New Series) 2015年第5期22卷 46-54页

作者： hongliang Li Yushu Chen School of Astronautics Harbin Institute of Technology

In order to clarify the effects of support structure on a dual-rotor machine,a dynamic model is established which takes into consideration the contact force of ball bearing and the cubic stiffness of elastic support. Bearing clearance,Hertz contact between the ball and race and the varying compliance effect are included in the model of ball bearing. The system response is obtained through numerical integration method,and the vibration due to the periodic change of bearing stiffness is investigated. The motions of periodic,quasiperiodic and even chaotic are found when bearing clearance is used as control parameter to simulate the response of rotor system. The results reveal two typical routes to chaos: quasi-periodic bifurcation and intermittent bifurcation. Large cubic stiffness of elastic support may cause jump and hysteresis phenomena in resonance curve when rotors run at the critical-speed region. The modeling results acquired by numerical simulation will contribute to understanding and controlling of the nonlinear behaviors of the dual-rotor system.

关键词： dual-rotor system ball bearing elastic support nonlinear dynamics bifurcation chaos

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Experimental Study on Product Characteristics of Typical Pulverized Coal Preheated by a Self-Preheating Burner

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Journal of Thermal Science 2023年第5期32卷 1912-1934页

作者： ZHANG Jinyang OUYANG Ziqu DING hongliang SU Kun Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang 212013China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

As the major primary energy source in China,coal has been proved to be capable to improve its physical and chemical characteristics by the pretreatment of the self-preheating *** this study,the effects of altering operating conditions including preheating temperature(T_(p))and primary air equivalence ratio(λ_(p))on preheating characteristics of three typical pulverized coal were investigated on a bench-scale test *** high-temperature coal gas compositions along the axis of the riser and at the outlet of the self-preheating burner were measured,and the coal char and coal tar produced in the preheating process were collected and analyzed *** results indicated that with the significant release of volatile and the occurrence of chemical reactions,cracks and micropores emerged on the surface of the particles,making the pore structure on the surface more developed,and T_(p)had the most significant effect on the structure of coal ***,there were evident differences in the corresponding operating conditions when the preheating characteristics of the three typical coal reached *** preheating had the strongest influence on the degree of anthracite *** respect to coal tar,the increase of T_(p)andλ_(p)further promoted its secondary cracking and oxidation,resulting in a decrease in production *** this study,for bituminous coal and lignite,a large amount of coal tar were produced during preheating and the highest production yields could reach 5.74%and 6.15%,*** for anthracite,the production yield was intensely low due to its own coal properties,all below 1.02%.

关键词： self-preheating fuel modification product characteristics coal particle structure coal tar

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Resolution of deep divergence of club fungi (phylum Basidiomycota)

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Synthetic and Systems Biotechnology 2019年第4期4卷 225-231页

作者： hongliang Mao Hao Wang T-Life Research Center Department of PhysicsFudan UniversityShanghai200433PR China

A long-standing question about the early evolution of club fungi(phylum Basidiomycota)is the relationship between the three major groups,Pucciniomycotina,Ustilaginomycotina and *** is unresolved whether Agaricomycotina are more closely related to Ustilaginomycotina or to *** we reconstructed the branching order of the three subphyla through two sources of phylogenetic signals,*** phylogenomic analysis and alignment-free phylogenetic ***,beyond congruency within the frame of standard phylogenomic analysis,our results consistently and robustly supported the early divergence of Ustilaginomycotina and a closer relationship between Agaricomycotina and Pucciniomycotina.

关键词： Fungi Basidiomycota Phylogenetics Phylogenomics CVTree

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Printable Kirigami-inspired Flexible and Soft Anthropomorphic Robotic Hand

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Journal of Bionic Engineering 2022年第3期19卷 668-677页

作者： Yunhol Chan Zion Tsz-Ho Tse hongliang Ren Department of Biomedical Engineering National University of SingaporeKent Ridge119077Singapore Department of Electronic Engineering The Chinese University of Hong Kong(CUHK)ShatinNew TerritoryHong KongChina Department of Electronic Engineering University of YorkNorth YorkshirefYO105DDUK

We present a kirigami-inspired design scheme for a robotic hand by 3D printable folds and *** unique contribution is the printable flexible hand,which provides flexibility and maneuverability that is unavailable in rigid robotic *** integration of sensors in the robotic system enables force adjustment for robotic systems applicable in the *** experimental results have shown that this design can perform everyday tasks through grasping and pinching different *** fingers can bend from 40 to 100 ***,the direct printable kirigami cuts and folds from soft elastic printable materials have significant potential for prosthetic *** printable kirigami design framework opens the possibility for future developments and modifications in numerous robotic applications.

关键词： Kirigami-inspired design Prosthetic Soft materials Three-dimensional printing

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Deepwater Turbidite Lobe Deposits:A Review of the Research Frontiers

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 283-300页

作者： ZHANG Leifu PAN Mao WANG hongliang School of Earth and Space Sciences Peking University School of Energy Resources China University of Geosciences

Deepwater/deep-marine turbidite lobes are the most distal part of a siliciclastic depositional system and hold the largest sediment accumulation on the seafloor. As many giant hydrocarbon provinces have been discovered within deepwater lobe deposits, they represent one of the most promising exploration targets for hydrocarbon industry. Deepwater exploration is characterized by high cost, high risk but insufficient data because of the deep/ultra–deepwater depth. A thorough understanding of the deepwater turbidite lobe architecture, hierarchy, stacking pattern and internal facies distribution is thus vital. Recently, detailed outcrop characterizations and high–resolution seismic studies have both revealed that the deepwater lobe deposits are characterized into four–fold hierarchical arrangements from ＂beds＂, to ＂lobe elements＂, to ＂lobes＂ and to ＂lobe complex＂. Quantitative compilations have shown that hierarchical components of lobe deposits have similar length to width ratios but different width to thickness ratios depending on different turbidite systems. At all hierarchical scales, sand–prone hierarchical lobe units are always separated by mud–prone bounding units except when the bounding units are eroded by their overlying lobe units thus giving rise to vertical amalgamation and connectivity. Amalgamations often occur at more proximal regions suggesting high flow energy. A mixed flow behavior may occur towards more distal regions, resulting in deposition of ＂hybrid event beds＂. These synthesized findings could（1） help understand the lobe reservoir distribution and compartmentalization therefore benefit the exploration and development of turbidite lobes within the deep marine basins（e.g. South China Sea） and（2） provide rules and quantitative constraints on reservoir modeling. In addition, the findings associated with deepwater turbidite lobes might be a good starting point to understand the sedimentology, architecture and hierarchy of turbidites in deep lacustrine

关键词： deepwater turbidite lobes architecture hierarchy quantitative characterization hybrid event beds

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Effects of the Secondary Air Excess Ratio on the Self-Preheating Combustion Characteristics and NOx,Emission of Semi-Coke

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Journal of Thermal Science 2023年第3期32卷 1263-1277页

作者： DING hongliang OUYANG Ziqu CAO Xiaoyang ZHU Shujun Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The effects of the secondary air excess ratio(λ_(2))on the self-preheating combustion characteristics and NO_(x)emission of semi-coke have been experimentally studied on a bench-scale test *** combustion of the high-temperature preheated fuel(coal gas&coal char)has been achieved in all experimental *** fire-observation windows,the combustion zone was transparent and no flame fronts were ***,differentλ_(2)in this study were basically within the common range of self-preheating combustion *** results manifested that the rapid ignition of coal gas and the recirculation of high-temperature flue gas resulted in relatively high combustion temperatures close to the secondary air nozzle *** the increase of.12,the unburned carbon content of fly ash increased slightly and combustion efficiencies of all experiments exceeded98%.Moreover,the exit NO_(x)emission was not reduced linearly,which was dissimilar from conventional air staging *** main reason was that the volatile-N was released in the self-preheating device,and the air staging method could not effectively reduce the char-NO_(x).In the course of the experiments,the lowest NO_(x)emission was 64.35 mg/m3(@6%O2)whenλ_(2)was 0.40.

关键词： self-preheating pulverized coal NO emission flameless combustion

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