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Influences of Inflow Condition on Non-Axisymmetric Flows in Turbine Exhaust Hoods

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Journal of Thermal Science 2008年第4期17卷 305-313页

作者： Jing-Lun FU jian-jun liu Institute of Engineering ThermophysicsChinese Academy of Sciences Beijing 100190 China

The complex 3D flow in a steam turbine exhaust hood model with different inlet swirl and inlet total pressure radial distributions has been simulated by employing CFX-5 and analyzed in this paper. It＇s found that the inlet tangential flow angle at hub has a negative effect on the exhaust hood performance, while a negative gradient of inlet total pressure radial distribution has a positive impact on the hood performances. It＇s also numerically con- firmed that a proper distribution of total pressure at hood inlet can successfully eliminate the negative effects caused by the inappropriate inlet swirl distribution and improve the hood aerodynamic performance.

关键词： turbine exhaust hood inflow conditions non-axisymmetric flow

A Degenerate KAM Theorem for Partial Differential Equations with Unbounded Perturbations

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Acta Mathematica Sinica,English Series 2024年第11期40卷 2719-2734页

作者： Mei Na GAO jian jun liu School of Mathematics Physics and Statistics Shanghai Polytechnic UniversityShanghai201209P.R.China School of Mathematics Sichuan UniversityChengdu610065P.R.China

In this paper,an infinite dimensional KAM theorem with unbounded perturbations and double normal frequencies is established under qualitative non-degenerate *** is an extension of the degenerate KAM theorem with bounded perturbations by Bambusi,Berti,Magistrelli,and *** applications,for derivative nonlinear Schrödinger equation with periodic boundary conditions,quasi-periodic solutions around constant solutions are obtained.

关键词： KAM theorem derivative nonlinear Schrödinger equation quasi-periodic solutions

A new pyrrolidone derivative from Pistacia chinensis

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Chinese Chemical Letters 2008年第1期19卷 65-67页

作者： jian jun liu Chang An Geng Xi Kui liu State Key Laboratory of Phytochemistry and Plant Resourses in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

A new N-phenyl-pyrrolidone derivative had been isolated from Pistacia chinesis Bunge. Its structure was elucidated as 4-hydroxy-5-（2-oxo-1-pyrrolidinyl）-benzoic acid, named pistaciamide on the basis of the 1D-NMR, DEPT, HMQC and HMBC spectroscopic techniques. 2007 Xi Kui liu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Pistacia chinensis 4-Hydroxy-5-(2-oxo-l-pyrrolidinyl)-benzoic acid Pistaciamide Pyrrolidone derivative

Simulation of 3D Flow in Turbine Blade Rows including the Effects of Coolant Ejection

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Journal of Thermal Science 2008年第2期17卷 111-115页

作者： jian-jun liu Bai-Tao AN Yun-Tao ZENG Institute of Engineering Thermophysics Chinese Academy of SciencesP. O. Box 2706 Beijing 100080 CHINA

This paper describes the numerical simulation of three-dimensional viscous flows in fir-cooled turbine blade rows with the effects of coolant ejection. A TVD Navier-Stokes flow solver incorporated with Baldwin-Lomax turbulence model and multi-grid convergence acceleration algorithm are used for the simulation. The influences of coolant ejection on the main flow are accounted by volumetric coolant source terms. Numerical results for a four-stage turbine are presented and discussed.

关键词： Numerical Simulation Air-Cooled Turbine Blade Row Coolant Ejection

Flowfield and Heat Transfer past an Unshrouded Gas Turbine Blade Tip with Different Shapes

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Journal of Thermal Science 2013年第2期22卷 128-134页

作者： jian-jun liu Peng LI Chao ZHANG Bai-Tao AN Institute of Engineering Thermophysics Chinese Academy of Sciences

This paper describes the numerical investigations of flow and heat transfer in an unshrouded turbine rotor blade of a heavy duty gas turbine with four tip configurations. By comparing the calculated contours of heat transfer coefficients on the flat tip of the HP turbine rotor blade in the GE-E3 aircraft engine with the corresponding ex- perimental data, the K：-o~ turbulence model was chosen for the present numerical simulations. The inlet and outlet boundary conditions for the turbine rotor blade are specified as the real gas turbine, which were obtained from the 3D full stage simulations. The rotor blade and the hub endwall are rotary and the casing is stationary. The influ- ences of tip configurations on the tip leakage flow and blade tip heat transfer were discussed. It＇s showed that the different tip configurations changed the leakage flow patterns and the pressure distributions on the suction surface near the blade tip. Compared with the flat tip, the total pressure loss caused by the leakage flow was decreased for the full squealer tip and pressure side squealer tip, while increased for the suction side squealer tip. The suction side squealer tip results in the lowest averaged heat transfer coefficient on the blade tip compared to the other tip configurations.

关键词： Turbine Rotor Blade Squealer Blade Tip Tip Leakage Flow Aerodynamic Loss Heat Transfer

The catassembled generation of naphthalene diimide coordination networks with lone pair-π interactions

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Science China Chemistry 2016年第11期59卷 1492-1497页

作者： Yong Chen jian-jun liu Chang-Rong Fan jun-Qian Li Mei-Jin Lin College of Chemistry Fuzhou University State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences

Catassembly is a new concept in molecular assembly that is analogous to catalysis in chemical synthesis. However, for most molecular-assembled processes, the catassembler contributions are rather inconspicuous due to the low activation barriers. As a result, few systems dealing with the catassembly are available until now. In this paper, we report that naphthalene diimide coordination networks are formed under the catassembly of lone-pair-bearing catassemblers(e.g., N,N-dimethylacetamide, N-methylpyrrolidin-2-one). During such molecular assembly, a stable transition state between the electron-deficient naphthalene diimide tectons and catassemblers via the less common lone pair-π interactions was observed, which is supposed to play the key role in the enhancement of coordination abilities of organic tectons and thus formation of the final coordination networks.

关键词： catassembly coordination network naphthalene diimide lone pair-π interaction

Properties of second harmonic generation in nonlinear optical crystals CsLiB_6O_(10) and K_2Al_2B_2O_7

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 77-80页

作者： SONG Chun-rong ZHAO jian-jun liu JIn Department of Basic Courses Ordnance Engineering College Shijiazhuang 050003 China

The phase-matching for nonlinear optical crystal, the nonlinear phase matching angle, effective nonlinear coefficient, walk-off angles, permitted angle, and permitted wavelength are obtained in type-I and type-II phase matching in ultraviolet （UV） nonlinear optical crystals CsLiB6O10 （CLBO） and K2Al2B2O7 （KABO） by detailed theoretical simulation. Through analysis and comparison, the phase matching characteristics of the second harmonic generation in the crystals are discussed when the wavelengths of the basic frequency lights turn continually.

关键词： nonlinear optical crystals phase matching second harmonic generation (SHG) properties

Data processing and error analysis for the CE-1 Lunar microwave radiometer

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Research in Astronomy and Astrophysics 2013年第3期13卷 359-372页

作者： jian-Qing Feng Yan Su jian-jun liu Yong-Liao Zou Chun-Lai Li National Astronomical Observatories Chinese Academy of Sciences

The microwave radiometer （MRM） onboard the Chang＇ E-1 （CE-I） lu- nar orbiter is a 4-frequency microwave radiometer, and it is mainly used to obtain the brightness temperature （TB） of the lunar surface, from which the thickness, temperature, dielectric constant and other related properties of the lunar regolith can be derived. The working mode of the CE-1 MRM, the ground calibration （including the official calibration coefficients）, as well as the acquisition and processing of the raw data are introduced. Our data analysis shows that TB increases with increasing frequency, decreases towards the lunar poles and is significantly affected by solar illumination. Our analysis also reveals that the main uncertainty in TB comes from ground calibration.

关键词： space vehicles -- instruments: microwave radiometer -- Moon: bright-ness temperature -- method: data processing -- error analysis

Rearrangement on surface structures by boride to enhanced cycle stability for LiNi0.80Co0.15Al0.05O2 cathode in lithium ion batteries

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Journal of Energy Chemistry 2020年第6期29卷 110-118,I0005页

作者： Shubiao Xia Wenjin Huang Xiang Shen Jiaming liu Feixiang Cheng jian-jun liu Xiaofei Yang Hong Guo Center for Yunnan-Guizhou Plateau Chemical Functional Materials and Pollution Control Qujing Normal UniversityQujing 655011YunnanChina School of Materials Science and Engineering Yunnan UniversityKunming 650091YunnanChina School of Metallurgy Engineering Jiangxi University of Science and TechnologyGanzhou 341003JiangxiChina Department of Mechanical and Materials Engineering University of Western OntarioLondonN6A 5B9OntarioCanada

The side reaction between the active material and liquid-electrolyte cause structural damage and particle pulverization is one of the important factors leading to the capacity decay of LiNi0.80Co0.15Al0.05O2(NCA)materials in Li ion batteries(LIBs).Surface modification is an effective strategy for NCA cathodes,which could alleviate the degradation associated with surface ***,a surface structure rearrangement of NCA cathode secondary particles was reported by in-situ forming a solid electrolyte *** LiBO2 is beneficial for alleviating the stress during charge/discharge process,thereby slowing down the rate of cracks formation in the secondary particles,which facilitates the Li+de-intercalation as well as prevents penetration of the liquid-electrolyte into the interior of the *** a result,the surface structure rearrangement NCA(RS-NCA)delivers a high discharge capacity of 202.5 m Ah g^-1 at 0.1 C,and exhibits excellent cycle stability with discharge capacity retaining 148 m Ah g^-1 after 200 cycles at 2 *** surface structure rearrangement approach provides a new viewpoint in designing high-performance high-voltage LIBs.

关键词： LiNi0.80Co0.15Al0.05O2 Surface structure rearrangement Particle pulverization Crack Cycle stability