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Effects of Inlet Circumferential Fluctuation on the Sweep Aerodynamic Performance of Axial Fans/Compressors

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Journal of Thermal Science 2013年第5期22卷 383-394页

作者： xingmin gui fang zhu Ke Wan donghai jin Aero-Engine Simulation Research Center Beijing University of Aeronautics and Astronautics

Swept blades have been widely used in the transonic fan/compressor of aircraft engines with the aids of 3D CFD simulation since the design concept of controlling the shock structure was firstly proposed and successfully tested by *** in the ***,some disadvantage phenomenon has also been induced by excessively 3D blade geometries on the structure stress insufficiency,vibration and *** confusion in the procedure of design practice leading us to recognize a new view on the flow mechanism of sweep aerodynamical induction: the new radial equilibrium established by the influence of inlet circumferential fluctuation(CF) changes the inlet flows of blading and induces the performance modification of axial fans/compressors *** view is verified by simplified models through numerical simulation and circumferentially averaged analysis in the present *** results show that the CF source items which originate from design parameters,such as the spanwise distributions of the loading and blading geometries,contribute to the changing of averaged incidence spanwise distribution,and further more affect the performance of axial fans/compressors with swept blades.

关键词： turbomachinery fans/compressors sweep aerodynamics quasi-3D method 3D flow

Effect of blade sweep on inlet flow in axial compressor cascades

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Chinese Journal of Aeronautics 2015年第1期28卷 103-111页

作者： Chang Hao zhu fang jin donghai gui xingmin School of Energy and Power Engineering Beihang University Gas Turbine Technology Institute Shanghai Electric Power Generation R&D Center

This paper presents comparative numerical studies to investigate the effects of blade sweep on inlet flow in axial compressor cascades. A series of swept and straight cascades was modeled in order to obtain a general understanding of the inlet flow field that is induced by sweep.A computational fluid dynamics（CFD） package was used to simulate the cascades and obtain the required three-dimensional（3D） flow parameters. A circumferentially averaged method was introduced which provided the circumferential fluctuation（CF） terms in the momentum equation.A program for data reduction was conducted to obtain a circumferentially averaged flow *** influences of the inlet flow fields of the cascades were studied and spanwise distributions of each term in the momentum equation were analyzed. The results indicate that blade sweep does affect inlet radial equilibrium. The characteristic of radial fluid transfer is changed and thus influencing the axial velocity distributions. The inlet flow field varies mainly due to the combined effect of the radial pressure gradient and the CF component. The axial velocity varies consistently with the incidence variation induced by the sweep, as observed in the previous literature. In addition, factors that might influence the radial equilibrium such as blade camber angles, solidity and the effect of the distance from the leading edge are also taken into consideration and comparatively analyzed.

关键词： compressor blade inlet sweep axial radial straight averaged momentum consistently

Application and Comparison of SST Model in Numerical Simulation of the Axial Compressors

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Journal of Thermal Science 2010年第4期19卷 300-309页

作者： YIN Song~1,jin donghai~2,gui xingmin~3 and zhu fang Aero-Engines Simulation Research Center,School of Jet Propulsion,Beijing University of Aeronautics and Astronautics, Beijing,100191,China Aero-Engines Simulation Research Center School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing China

The shear-stress transport(SST)turbulence model is incorporated into Navier-Stokes equations to simulate a turbomachinery flowfield.A staggered finite volume method is used to make the mean flow equations and turbulence model equations strongly coupled and enhance the stability of the numerical *** implicit treatment of the source terms is applied to the SST model.A steady state solution is obtained using five-stage Runge-Kutta time-stepping scheme with local time stepping and residual smoothing to accelerate convergence. The wall distance d,a key parameter in the SST model,is solved by a partial differential *** validations of the code are conducted on rotor 37,wp11 at design and off-design conditions by comparison with measurements and the Spalart-Allmaras(SA)turbulence *** flow within the tip is calculated with a multi-block grid.

关键词： SST model staggered finite volume method turbomachinery simulation multi-block grid

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周向平均方法在某风扇/增压级分析中的应用

航空学报 2014年第1期35卷 132-140页

作者：万科朱芳金东海桂幸民北京航空航天大学能源与动力工程学院航空发动机数值仿真中心北京100191

通过对三维(3D)Navier-Stokes方程进行周向平均,得到了通流模型的控制方程,对其采用时间推进有限体积方法进行数值求解。为实现风扇/增压级在设计初期的快速性能评估,考察了周向平均方法在风扇/增压级分析中的准确性。分别利用NUMECA三... 详细信息

通过对三维(3D)Navier-Stokes方程进行周向平均,得到了通流模型的控制方程,对其采用时间推进有限体积方法进行数值求解。为实现风扇/增压级在设计初期的快速性能评估,考察了周向平均方法在风扇/增压级分析中的准确性。分别利用NUMECA三维数值模拟软件和周向平均通流模型(CAM)对某高通流风扇/增压级进行了性能分析,从对比结果来看,周向平均通流模型在近设计点给出了与三维数值模拟十分接近的特性参数,最大误差不超过2.0%。在风扇转子中,由于周向平均通流模型能捕获通道激波,其物理本质与三维平均结果有所区别,因此径向参数分布与三维有所差异。而在亚声速流动下的增压级及外涵道各叶片排出口参数的径向分布与三维数值模拟结果都能很好地吻合。

关键词：通流模型周向平均风扇增压级性能数值模拟

Cholesterol oxidase biosensor based on a glassy carbon electrode modified with Nafion and methyl viologen

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Chinese Journal of Chemistry 1994年第4期12卷 343-347页

作者： jin, Li-Tong ZHAO, gui-zhu fang, Yu-ZhiDepartment of Chemistry, East China Normal University, Shanghai 200062, China Department of Chemistry East China Normal University Shanghai 200062 China

Cholesterol oxidase biosensor has been constructed by using bovine serum albumin and glutaraldehyde as cross linker to immobilize cholesterol oxidase and cholesterol esterase on a glassy carbon electrode modified with Nafion and methyl viologen. The biosensor has been used to determine total cholesterol in blood. The linear range of the determination is 2.5×10~7 to 1.0×10-4 mol/L. The detection limit is about 5.0×10~8 mol/L. The response time is 12 s. This biosensor has the advantage of high selectivity, sensitivity and short response time.

关键词： Biosensor cholesterol oxidase enzyme electrode.

Localized Excitations of （2＋1）-Dimensional Korteweg-de Vries System Derived from a Periodic Wave Solution

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Communications in Theoretical Physics 2007年第2期47卷 275-281页

作者： QIANG Ji-Ye FEI jin-Xi CAI gui-Ping ZHENG Chun-Long College of Physics and Mathematics Zhejiang Lishui University Lishui 323000 China Biophysics Department Yunnan Agricultural University Kunming 650201 China Institute of Educational Science Wenzhou University Wenzhou 325035 China

With the aid of an improved projective approach and a linear variable separation method, new types of variable separation solutions （including solitary wave solutions, periodic wave solutions, and rational function solutions） with arbitrary functions for （2＋1）-dimensional Korteweg-de Vries system are derived. Usually, in terms of solitary wave solutions and rational function solutions, one can find some important localized excitations. However, based on the derived periodic wave solution in this paper, we find that some novel and significant localized coherent excitations such as dromions, peakons, stochastic fractal patterns, regular fractal patterns, chaotic line soliton patterns as well as chaotic patterns exist in the KdV system as considering appropriate boundary conditions and/or initial qualifications.

关键词： improved projective approach KdV system chaos soliton fractal

A chromosome-scale genome sequence of pitaya (Hylocereus undatus) provides novel insights into the genome evolution and regulation of betalain biosynthesis

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Horticulture Research 2021年第1期8卷 2260-2274页

作者： Jian-ye Chen fang-fang Xie Yan-ze Cui Can-bin Chen Wang-jin Lu Xiao-di Hu Qing-zhu Hua jing Zhao Zhi-jiang Wu Dan Gao Zhi-ke Zhang Wen-kai Jiang Qing-ming Sun gui-bing Hu Yong-hua Qin State Key Laboratory for Conservation and Utilization of Subtropical Agrobioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(South China) Ministry of Agriculture and Rural Affairs/Lingnan Guangdong Laboratory of Modern AgricultureCollege of HorticultureSouth China Agricultural University510642 GuangzhouGuangdongChina Novogene Bioinformatics Institute 100083 BeijingChina Horticulture Research Institute Guangxi Academy of Agricultural Sciences530007 NanningGuangxiChina Institute of Fruit Tree Research Guangdong Academy of Agricultural Sciences/Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization(MOA)/Guangdong Province Key Laboratory of Tropical and Subtropical Fruit Tree Research510640 GuangzhouChina

Pitaya(Hylocereus)is the most economically important fleshy-fruited tree of the Cactaceae family that is grown worldwide,and it has attracted significant attention because of its betalain-abundant ***,the lack of a pitaya reference genome significantly hinders studies focused on its evolution,as well as the potential for genetic improvement of this ***,we employed various sequencing approaches,namely,PacBio-SMRT,Illumina HiSeq paired-end,10×Genomics,and Hi-C(high-throughput chromosome conformation capture)to provide a chromosome-level genomic assembly of‘GHB’pitaya(***,2n=2x=22 chromosomes).The size of the assembled pitaya genome was 1.41 Gb,with a scaffold N50 of~127.15 *** total,27,753 protein-coding genes and 896.31Mb of repetitive sequences in the *** genome were *** has undergone a WGT(whole-genome triplication),and a recent WGD(whole-genome duplication)occurred after the gamma event,which is common to the other species in Cactaceae.A total of 29,328 intact LTR-RTs(~696.45Mb)were obtained in ***,of which two significantly expanded lineages,Ty1/copia and Ty3/gypsy,were the main drivers of the expanded genome.A high-density genetic map of F1 hybrid populations of‘GHB’×‘Dahong’pitayas(***)and their parents were constructed,and a total of 20,872 bin markers were identified(56,380 SNPs)for 11 linkage *** importantly,through transcriptomic and WGCNA(weighted gene coexpression network analysis),a global view of the gene regulatory network,including structural genes and the transcription factors involved in pitaya fruit betalain biosynthesis,was *** data present a valuable resource for facilitating molecular breeding programs of pitaya and shed novel light on its genomic evolution,as well as the modulation of betalain biosynthesis in edible fruits.

关键词： evolution expanded linkage

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湍流模型对压气机数值模拟精度的影响

航空动力学报 2010年第12期25卷 2683-2689页

作者：尹松金东海朱芳桂幸民北京航空航天大学能源与动力工程学院北京100191

开发了一个求解叶轮机全三维黏性流场的程序,采用了目前叶轮机数值模拟中常用的且模拟性能较好的三种湍流模型:k-ε模型,k-ω模型,Spalart-All maras(S-A)模型,计算了跨声压气机NASA(National Aeronautics and Space Administration)Rot... 详细信息

开发了一个求解叶轮机全三维黏性流场的程序,采用了目前叶轮机数值模拟中常用的且模拟性能较好的三种湍流模型:k-ε模型,k-ω模型,Spalart-All maras(S-A)模型,计算了跨声压气机NASA(National Aeronautics and Space Administration)Rotor 37的流场,并与实验进行了性能参数、三维流场和角区流动的对比分析.考察在相同的数值计算平台上进行比较这几个湍流模型对压气机的数值模拟性能的影响.最终结果表明:对于具有强剪切、存在分离流的复杂的叶轮机三维流场来说,k-ω模型数值模拟精度更高,相比其他两个模型具有一定的优势.

关键词：压气机三维黏性流场数值模拟角区流动湍流模型

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某四级风扇特性计算的三维数值模拟

航空动力学报 2010年第6期25卷 1366-1373页

作者：尹松金东海朱芳桂幸民北京航空航天大学能源与动力工程学院北京100191

利用自主开发的程序对某四级风扇进行了特性计算,一方面是为了发动机整机的匹配,另一方面是为了校核程序对多级压气机的数值模拟精度.程序采用标准k-ε湍流模型计算湍流黏性系数,为了避免计算过程中由湍流模型方程带来的数值刚性问题,... 详细信息

利用自主开发的程序对某四级风扇进行了特性计算,一方面是为了发动机整机的匹配,另一方面是为了校核程序对多级压气机的数值模拟精度.程序采用标准k-ε湍流模型计算湍流黏性系数,为了避免计算过程中由湍流模型方程带来的数值刚性问题,对湍流模型方程中的源项作了隐式处理.转静子之间的数据传递采用了掺混界面法.通过对一个单级风扇进行计算,并与常用的几种商用软件计算结果以及实验结果进行对比,初步验证了程序计算结果的可靠性.进一步对某四级风扇进行了计算分析,发现程序计算精度较好,可用于工程设计中.

关键词：多级压气机数值模拟 k-ε湍流模型隐式处理掺混界面