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Experimental and Numerical Investigation of Non-synchronous Blade Vibration Excitation in a Transonic Axial Compressor

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Journal of Thermal Science 2024年第2期33卷 602-610页

作者： wang songbai WU Yadong CHEN Yong CAO Zhipeng School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China AECC Sichuan Gas Turbine Establishment Chengdu610500China

The complex flow phenomenon of rotating instability(RI) and its induced non-synchronous vibration(NSV) have become a significant challenge as they continuously increase aerodynamic *** study aims to provide an understanding of the non-synchronous blade vibration phenomenon caused by the rotating instability of a transonic axial compressor *** this case,blade vibrations and non-synchronous excitation are captured by strain gauges and unsteady wall pressure transducer *** numerical simulations for a full-annulus configuration are used to obtain the non-synchronous flow *** results show that the first-stage rotor blade exhibits an NSV close to the first bending mode;NSV is accompanied by a sharp increase in pressure pulsation;amplitude can reach 20%,and unsteady aerodynamic frequency will lock in a structural mode frequency when the blade vibrates in a large-amplitude *** predicted NSV frequency aligns well with the experimental *** dominant mode of circumferential instability flow structure is approximately 47% of the number blades,and the cell size occupies 2-3 pitches in the circumferential *** full-annulus unsteady simulations demonstrate that the streamwise oscillation of the shedding and reattachment vortex structure is the main cause of NSV owing to the strong interaction between the tip leakage and separation vortices near the suction surface.

关键词： non-synchronous vibration transonic axial compressor rotor blade rotating instabilities unsteady flow

Weak Hardy-type spaces associated with ball quasi-Banach function spaces I:Decompositions with applications to boundedness of Calderón-Zygmund operators

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Science China Mathematics 2021年第9期64卷 2007-2064页

作者： Yangyang Zhang Dachun Yang Wen Yuan songbai wang Laboratory of Mathematics and Complex Systems(Ministry of Education of China) School of Mathematical SciencesBeijing Normal UniversityBeijing100875China College of Mathematics and Statistics Hubei Normal UniversityHuangshi435002China

Let X be a ball quasi-Banach function space on R^(n).In this article,we introduce the weak Hardytype space WH_(X)(R^(n)),associated with X,via the radial maximal *** that the powered HardyLittlewood maximal operator satisfies some Fefferman-Stein vector-valued maximal inequality on X as well as it is bounded on both the weak ball quasi-Banach function space WX and the associated space,we then establish several real-variable characterizations of WH_(X)(R^(n)),respectively,in terms of various maximal functions,atoms and *** an application,we obtain the boundedness of Calderón-Zygmund operators from the Hardy space H_(X)(R^(n))to WH_(X)(Rn),which includes the critical *** these results are of wide ***,when X:=M^(q)_(p)(R^(n))(the Morrey space),X:=L^(p)(R^(n))(the mixed-norm Lebesgue space)and X:=(EΦq)t(Rn)(the Orlicz-slice space),which are all ball quasi-Banach function spaces rather than quasiBanach function spaces,all these results are even *** to the generality,more applications of these results are predictable.

关键词： ball quasi-Banach function space weak Hardy space Orlicz-slice space maximal function atom molecule Calderón-Zygmund operator

Solderability and intermetallic compounds formation of Sn-9Zn-xAg lead-free solders wetted on Cu substrate

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Rare Metals 2009年第6期28卷 656-660页

作者： CHEN Wenxue XUE songbai wang Hui wang Jianxin HAN Zongjie College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The eutectic Sn-9Zn alloy was doped with Ag （0 wt.%-1 wt.%） to form Sn-9Zn-xAg lead-free solder alloys. The effect of the addition of Ag on the microstructure and solderability of this alloy was investigated and intermetallic compounds （IMCs） formed at the solder/Cu interface were also examined in this study. The results show that, due to the addition of Ag, the microstructure of the solder changes. When the quantity of Ag is lower than 0.3 wt.%, the needle-like Zn-rich phase decreases gradually. However, when the quantity of Ag is 0.5 wt.%-1 wt.%, Ag-Zn intermetallic compounds appear in the solder. In particular, adding 0.3 wt.% Ag improves the wetting behavior due to the better oxidation resistance of the Sn-9Zn solder. The addition of an excessive amount of Ag will deteriorate the wetting property because the gluti- nosity and fluidity of Sn-9Zn-（0.5, 1）Ag solder decrease. The results also indicate that the addition of Ag to the Sn-Zn solder leads to the precipitation of ε-AgZn3 from the liquid solder on preformed interracial intermetallics （CusZn8）. The peripheral AgZn3, nodular on the Cu5Zn8 IMCs layer, is likely to be generated by a peritectic reaction L ＋ γ-Ag5Zns→AgZn3 and the following crystallization of AgZn3.

关键词： soldering materials lead-free solder wettability intermetallic compounds

Morrey Spaces Associated to the Sections and Singular Integrals

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Journal of Mathematical Research with Applications 2017年第4期37卷 455-465页

作者： songbai wang Jinqiu WEN College of Mathematics and Statistics Hubei Normal University

In this paper, we define the Morrey spaces MFp,q（Rn） and the Campanato spaces EFp,q（R~n） associated with a family F of sections and a doubling measure μ, where F is closely related to the Monge-Amp`ere equation. Furthermore, we obtain the boundedness of the Hardy-Littlewood maximal function associated to F, Monge-Amp`ere singular integral operators and fractional integrals on MFp,q（R~n）. We also prove that the Morrey spaces MFp,q（R~n）and the Campanato spaces EFp,q（R~n） are equivalent with 1 ≤ q ≤ p < ∞.

关键词： Morrey space Campanato space Monge-Ampère singular integral

Saturation Ion Current Densities in Inductively Coupled Hydrogen Plasma Produced by Large-Power Radio Frequency Generator

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Plasma Science and Technology 2016年第9期18卷 907-911页

作者： wang songbai LEI Guangjiu BI Zhenhua H. GHOMI YANG Size LIU Dongping College of Physics and Information Engineering Fuzhou UniversityFuzhou 350108China Southwestern Institute of Physics Chengdu 610041China School of Physics and Materials Engineering Dalian Nationalities UniversityDalian 116600China Laser and Plasma Research Institute Shahid Beheshti UniversityEvinTehrarIran School of Physics and Mechanical&Electrical Engineering Xiamen UniversityXiamen 361005China

An experimental investigation of the saturation ion current densities （Jions） in hydrogen inductively coupled plasma （ICP） produced by a large-power （2-32 kW） radio frequency （RF） generator is reported, then some reasonable explanations are given out. With the increase of RF power, the experimental results show three stages： in the first stage （2-14 kW）, the electron temperature will rise with the increase of RF power in the ICP, thus, the Jions increases continually as the electron temperature rises in the ICP. In the second stage （14 20 kW）, as some H- ions lead to the mutual neutralization （MN）, the slope of Jio^s variation firstly decreases then increases. In the third stage （20-32 kW）, both the electronic detachment （ED） and the associative detachment （AD） in the ICP result in the destruction of H- ions, therefore, the increased amplitude of the Jions in the third stage is weaker than the one in the first stage. In addition, with the equivalent transformer model, we successfully Explain that the Jions at different radial locations in ICP has the same rule. Finally, it is found that the Jions has nothing to do with the outer/inner puffing gas pressure ratio, which is attributed to the high-speed movement of hydrogen molecules.

关键词： saturation ion current densities large-power RF generator outer/innerpuffing gas pressure ratio H- ion transformer model

Weighted Estimates for Marcinkiewicz Integrals with Non-Doubling Measures

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Journal of Mathematical Research with Applications 2012年第2期32卷 223-234页

作者： songbai wang,Yinsheng JIANG,Baode LI College of Mathematics and System Sciences,Xinjiang University,Xinjiang 830046,P.R.China College of Mathematics and System Sciences Xinjiang University

Let μ be a nonnegative Radon measure on R d which satisfies the growth condition μ(B(x,r)) ≤ C0rn for all x ∈Rd and r >0,where C0 is a fixed constant and 0 详细信息

Let μ be a nonnegative Radon measure on R d which satisfies the growth condition μ(B(x,r)) ≤ C0rn for all x ∈Rd and r >0,where C0 is a fixed constant and 0

关键词： maximal singular integrals Muckenhoupt type weights sharp maximal operators non-doubling measures.

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粒子侵蚀问题的研究

推进技术 1993年第1期14卷 40-45页

作者：王松柏哈尔滨船舶工程学院

固体火箭发动机排出的高温、高速燃气对热防护材料有很大的侵蚀作用,特别是燃气中的氧化铝粒子对材料的侵蚀起主要作用。为此,本文对粒子侵蚀问题做了理论分析和实验研究;提供了一个用以计算粒子侵蚀速度的方法和公式。最后的算例表明,... 详细信息

固体火箭发动机排出的高温、高速燃气对热防护材料有很大的侵蚀作用,特别是燃气中的氧化铝粒子对材料的侵蚀起主要作用。为此,本文对粒子侵蚀问题做了理论分析和实验研究;提供了一个用以计算粒子侵蚀速度的方法和公式。最后的算例表明,此方法可行,并具有足够的精度。

关键词：颗粒侵蚀喷管气流火箭发动机

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喷管喉部沉积层的初始沉积速度预估

推进技术 1989年第5期10卷 25-30,18页

作者：王松柏哈尔滨船舶工程学院

本文以两种理论分析方法分析了固体火箭发动机喷管喉部沉积层的形成规律.其一,针对喉部沉积层是喉部上游沉积物流动的结果的论点,以粘性层流理论分析了液体薄层的流动性质,并对此论点提出了不同看法.其二,以粒子的宏观运动规律出发,推... 详细信息

本文以两种理论分析方法分析了固体火箭发动机喷管喉部沉积层的形成规律.其一,针对喉部沉积层是喉部上游沉积物流动的结果的论点,以粘性层流理论分析了液体薄层的流动性质,并对此论点提出了不同看法.其二,以粒子的宏观运动规律出发,推导粒子的初始沉积速度公式,并取得成功.从而弥补了在沉积问题的理论分析中必须借助于实验资料的不足.

关键词：喷管喷部喷管气流沉积火箭发动机

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加权耦合型空间上的多线性算子（英文）

数学进展 2018年第6期47卷 881-905页

作者：王松柏李朋湖北师范大学数学与统计学院黄石湖北435002 中国工程物理研究院研究生院北京100088

本文证明了,如果满足特定点态估计的多线性算子T和它的多线性交换子、迭代交换子分别在乘积加权Lebesgue空间上有界,那么它们也在加权耦合型空间上有界.作为应用,我们说明了多线性Littlewood-Paley函数、具有卷积或非卷积核的多线性Marc... 详细信息

本文证明了,如果满足特定点态估计的多线性算子T和它的多线性交换子、迭代交换子分别在乘积加权Lebesgue空间上有界,那么它们也在加权耦合型空间上有界.作为应用,我们说明了多线性Littlewood-Paley函数、具有卷积或非卷积核的多线性Marcinkiewicz积分和它们的线性交换子和迭代交换子均在乘积加权耦合型空间上有界.引入耦合型Campanato空间后,我们得到了多线性分数次积分算子是从耦合型空间到耦合型Campanato空间上有界的.我们的结果对于线性的分数次积分算子也是新的.

关键词：耦合空间 Ap权多线性算子耦合型Campanato空间