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Molecular dynamics simulations of collision cascades in polycrystalline tungsten
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作者 Lixia Liu Mingxuan Jiang +3 位作者 Ning Gao Yangchun Chen Wangyu Hu Hiuqiu Deng 《Chinese Physics B》 2025年第4期468-476,共9页
Using molecular dynamics methods,simulations of collision cascades in polycrystalline tungsten(W)have been conducted in this study,including different primary-knock-on atom(PKA)directions,grain sizes,and PKA energies ... Using molecular dynamics methods,simulations of collision cascades in polycrystalline tungsten(W)have been conducted in this study,including different primary-knock-on atom(PKA)directions,grain sizes,and PKA energies between 1 keV and 150 keV.The results indicate that a smaller grain size leads to more defects forming in grain boundary regions during cascade processes.The impact of high-energy PKA may cause a certain degree of distortion of the grain boundaries,which has a higher probability in systems with smaller grain sizes and becomes more pronounced as the PKA energy increases.The direction of PKA can affect the formation and diffusion pathways of defects.When the PKA direction is perpendicular to the grain boundary,defects preferentially form near the grain boundary regions;by contrast,defects are more inclined to form in the interior of the grains.These results are of great significance for comprehending the changes in the performance of polycrystalline W under the high-energy fusion environments and can provide theoretical guidance for further optimization and application of W-based plasma materials. 展开更多
关键词 collision cascades molecular dynamics simulations TUNGSTEN POLYCRYSTALLINE
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Tip Clearance Flows in Turbine Cascades 被引量:5
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作者 李伟 乔渭阳 孙大伟 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期193-199,共7页
This article describes the effects of some factors on the tip clearance flow in axial linear turbine cascades. The measurements of the total pressure loss coefficient are made at the cascade outlets by using a five-ho... This article describes the effects of some factors on the tip clearance flow in axial linear turbine cascades. The measurements of the total pressure loss coefficient are made at the cascade outlets by using a five-hole probe at exit Mach numbers of 0.10, 0.14 and 0.19. At each exit Mach number, experiments are performed at the tip clearance heights of 1.0%, 1.5%, 2.0%, 2.5% and 3.0% of the blade height. The effects of the non-uniform tip clearance height of each blade in the pitchwise direction are also studied. The results show that at a given tip clearance height, generally, total pressure loss rises with exit Mach numbers proportionally. At a fixed exit Mach number, the total pressure loss augments nearly proportionally as the tip clearance height increases. The increased tip clearance heights in the tip regions of two adjacent blades are to be blame for the larger clearance loss of the center blade. Compared to the effects of the tip clearance height, the effects of the exit Mach number and the pitchwise variation of the tip clearance height on the cascade total pressure loss are so less significant to be omitted. 展开更多
关键词 tip clearance flow turbine cascade tip clearance height total pressure loss coefficient
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Interactions of primary insult biomechanics and secondary cascades in spinal cord injury: implications for therapy 被引量:5
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作者 Michael B.Orr John C.Gensel 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第10期1618-1619,共2页
The complex and variable nature of traumatic spinal cord inju- ry (SCI) presents a unique challenge for translational research. SCI is not bound by any demographic nor is it limited to specific injury biomechanics.
关键词 SCI Interactions of primary insult biomechanics and secondary cascades in spinal cord injury:implications for therapy
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AN APPLICATION OF TOPOLOGICAL ANALYSIS TO STUDYING THE THREE-DIMENSIONAL FLOW IN CASCADES;PART I—TOPOLOGICAL RULES FOR SKIN-FRICTION LINES AND SECTION STREAMLINES 被引量:2
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作者 康顺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第5期489-495,共7页
Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rul... Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rules are (1) for a rotor cascade without shroud band, the total number of nodal points equals that the saddle points on the skin-friction line vector fields in eachpitch range; (2) for an annular or straight cascade with no-clearances at blade ends, the total number of saddle points is two more than that of nodal points on the skin-friction line fields in a pitch; (3) the total number of saddles in the secondary flow fields on cross-sections in cascade is one less than that of nodes; (4) in the section streamline vector fields on a meridian surface penetrating a flow passage, and on leading and trailing edge sections, the total number of nodes is equal to that of saddles; (5) on the streamline vector fields of a blade-to-blade surface, the total number of nodes is one less than that of saddles. 展开更多
关键词 node TOPOLOGICAL RULES FOR SKIN-FRICTION LINES AND SECTION STREAMLINES AN APPLICATION OF TOPOLOGICAL ANALYSIS TO STUDYING THE THREE-DIMENSIONAL FLOW IN cascades PART I
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Molecular dynamics simulations of displacement cascades in Fe-10%Cr systems
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作者 郁刚 马雁 +1 位作者 蔡军 陆道纲 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期314-320,共7页
Molecular dynamics simulations of the displacement cascades in Fe 10%Cr systems are used to sinmlate the primary knocked-on atom events of the irradiation damage at temperatures 300, 600, and 750 K with primary knocke... Molecular dynamics simulations of the displacement cascades in Fe 10%Cr systems are used to sinmlate the primary knocked-on atom events of the irradiation damage at temperatures 300, 600, and 750 K with primary knockedon atom energies between 1 and 15 keV. The results indicate that the vacancies produced by the cascade are all in the central region of the displacement cascade. During the cascade, all recoil Fe and Cr atoms combine with each other to form Fe Cr or Fe Fe interstitial dumbbells as well as interstitial clusters. The number and the size of interstitial clusters increase with the energy of the primary knocked-on atom and the temperature. A few large clusters consist of a large number of lee interstitials with a few Cr atoms, the rest are lee Cr clusters with small and medium sizes. The interstitial dumbbells of Fe lee and Fe-Cr are in the (111)and (110) series directions, respectively. 展开更多
关键词 molecular dynamics simulations displacement cascades irradiation damage primary knocked-on atom
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Biocatalytic bis-C-alkylation of phenolics using one-pot cascades with promiscuous C-glycosyltransferase and prenyltransferase
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作者 Dawei Chen Lili Sun +3 位作者 Ridao Chen Kebo Xie Lin Yang Jungui Dai 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2018年第4期241-250,共10页
C-glycosylation and C-prenylation are two important C-C-bond forming reactions for preparation,diversification and structural modification of natural/unnatural products with pharmacological activities.Here,we describe... C-glycosylation and C-prenylation are two important C-C-bond forming reactions for preparation,diversification and structural modification of natural/unnatural products with pharmacological activities.Here,we described unprecedented enzymatic cascades to C-glycosylate/prenylate different acyl resorcinol derivatives in stepwise,one-pot reactions by combining two promiscuous enzymes,MiCGT,a C-glycosyltransferase,and AtaPT,a prenyltransferase.Five novel bis-C-alkylated products were obtained and structurally identified by MS and NMR spectroscopic data as well as comparison with the literature.This study provided a potential synthetic strategy for synthesizing structurally novel and diverse compounds bearing both C-glycosyl and C-prenyl moieties by a two-step,enzymatic bis-C-alkylation. 展开更多
关键词 Bis-C-alkylation Enzymatic glycosylation Enzymatic prenylation Enzyme cascades
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Evaluation of Cr Concentration Effect on Displacement Cascades in Fe-Cr Alloys with Piecewise Potential
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作者 Xinhua Yang Ying Zheng Jie Li 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2020年第2期239-250,共12页
A piecewise potential was constructed with combination of the concentration-dependent EAM(CD-EAM)potential and Ziegler-Biersack-Littmark(ZBL)potential,and the displacement cascades in random Fe-Cr binary alloys with a... A piecewise potential was constructed with combination of the concentration-dependent EAM(CD-EAM)potential and Ziegler-Biersack-Littmark(ZBL)potential,and the displacement cascades in random Fe-Cr binary alloys with a wide range of Cr concentration from 0 to 20%were simulated to evaluate the effect of Cr concentration on defect formation and evolution during the cascades.The Cr concentration has little or no effect on the fraction of vacancy clusters,the number of surviving Frenkel pairs,or the self-interstitial and vacancy cluster sizes and a slight effect on the peak time and peak defect number,but a considerable effect on the Cr enrichment in the peak and surviving defects in the cascaded Fe-Cr alloys.With the increase in Cr concentration,the Cr enrichment in the peak and surviving defects exhibits a downtrend.The higher enrichment degree in the surviving defects than in the peak defects shows more difficult recombination of Cr SIAs with vacancies. 展开更多
关键词 Fe-Cr alloy Cr concentration Molecular dynamics Displacement cascades
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Proinflammatory Signaling Cascades of Periodontopathic Oral Pathogen <i>Porphyromonas gingivalis</i>
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作者 Bronislaw L. Slomiany Amalia Slomiany 《Journal of Biosciences and Medicines》 2018年第5期63-88,共26页
Porphyromonas gingivalis, is the most prominent member of the bacteria flora associated with pathogenesis of periodontitis, a chronic inflammatory disease resulting in tooth loss. The extent of oral mucosal reaction t... Porphyromonas gingivalis, is the most prominent member of the bacteria flora associated with pathogenesis of periodontitis, a chronic inflammatory disease resulting in tooth loss. The extent of oral mucosal reaction to P. gingivalis invasion relays heavily on Toll-like receptors (TLRs) that recognize structurally common motifs of pathogens and initiate antibacterial responses. Among the virulence factors of P. gingivalis implicated in TLRs activation and triggering inflammatory responses leading to the development of periodontitis is the bacterium cell-wall lipopolysaccharide (LPS). The engagement by the LPS of oral mucosal TLR4 leads to initiation of signaling events characterized by the activation of mitogen-activated protein kinase (MAPK) and IκB-kinase complex (IKK) cascades, induction of phosphoinositide-specific phospholipase C (PLC)/protein kinase C (PKC)/PI3K pathway, up-regulation in TGF-α ectodomain shedding and EGFR transactivation, and the amplification of proinflammatory signals by spleen tyrosine kinase (Syk). These events, in turn, exert their control over transcription factors implicated in the induction of the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) genes that lead to up-regulation in the inflammatory mediators, PGE2 and NO. The systems involved in transcription factors activation, furthermore, remain under additional regulatory control through S-nitrosylation. Moreover, the LPS-induced TLR4 activation provides a docking site for Syk, the activation of which leads to amplification of the inflammatory signals by affecting transcription factors activation and their assembly to transcriptional complexes. Interestingly, the extent of oral mucosal inflammatory response to P. gingivalis remains under modulatory influence by two biologically active peptide hormones, leptin and ghrelin. Therefore, the presence of these multifunctional peptides in oral mucosa and saliva may be of significance in countering the destructive consequences of P. gingivalis—induced chronic mucosal inflammation that characterizes periodontitis. 展开更多
关键词 P. gingivalis PERIODONTAL Disease ORAL MUCOSA Inflammatory Response LPS TLR4 Signaling cascades
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加拿大Cascades公司关停美国缅因州的脱墨浆工厂
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《中华纸业》 CAS 2016年第13期80-80,共1页
加拿大Cascades Inc.公司近期宣布将永久性的关停其位于美国缅因州的脱墨浆工厂。据称该工厂的生产将在7月8日停止,而工厂将在7月15日关停。该工厂雇用员工约有45名。据Cascades公司称,之所以关停此工厂,主要是印刷和书写纸市场的快速萎... 加拿大Cascades Inc.公司近期宣布将永久性的关停其位于美国缅因州的脱墨浆工厂。据称该工厂的生产将在7月8日停止,而工厂将在7月15日关停。该工厂雇用员工约有45名。据Cascades公司称,之所以关停此工厂,主要是印刷和书写纸市场的快速萎缩,导致脱墨浆市场情况受到负面影响, 展开更多
关键词 脱墨浆 cascades 美国缅因州 书写纸
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Study on Integrated Automation of Three Gorges Cascades
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作者 Fang Huiqin (Nanjing Automation Research Institute) 《Electricity》 1998年第4期30-33,共4页
This paper briefly describes the basic situation and features of Three Gorges Cascade, discusses the principle,functions, structure of the integrated automation system, and explains advanced techniques and principle a... This paper briefly describes the basic situation and features of Three Gorges Cascade, discusses the principle,functions, structure of the integrated automation system, and explains advanced techniques and principle and associated experiments of its monitoring and control 展开更多
关键词 TGC Study on Integrated Automation of Three Gorges cascades
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Cascades公司用垃圾作纸厂能源
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《造纸信息》 2004年第4期37-37,共1页
关键词 cascades公司 垃圾 能源 综合利用 造纸企业
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Cascades公司投资新建卫生纸生产线
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作者 李萌 《造纸信息》 2011年第7期65-65,共1页
Cascades公司近日宣布将投资超过3000万加元,在Candiac卫生纸厂新建一条卫生纸生产线。该生产线采用了福伊特的"等效TAD"技术生产超级优质卫生纸,且环境友好。
关键词 cascades公司 投资 卫生纸 生产线
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Cascades公司并购Papersource加工厂
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作者 陈海昌(译) 孙静(审校) 《生活用纸》 2012年第2期52-52,共1页
Cascades公司并购Papersource加工厂50%剩余股份后提高了其在北美的地位。并购的现金价为6,000万美元。
关键词 cascades公司 Papersource加工厂 生活用纸 品牌 产品质量
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加拿大Cascades公司的Lachute纸厂转产擦手纸
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作者 陈祥津 《生活用纸》 2004年第12期60-60,共1页
关键词 加拿大cascades公司 Lachute纸厂 擦手纸 生产计划
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Cascades公司进军智能纸(TM)市场
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作者 王成海 《造纸信息》 2010年第9期49-49,共1页
经过5年的研究开发,Cascades正以一种新型方式进军智能纸(TM)市场,这种新型方式是抵御手接触的细菌。近日,该公司总经理宣布Cascades正在进入这一潜力巨大的市场。对这一新兴市场初期推出的是一种能够产生持续抗菌作用的擦手纸巾... 经过5年的研究开发,Cascades正以一种新型方式进军智能纸(TM)市场,这种新型方式是抵御手接触的细菌。近日,该公司总经理宣布Cascades正在进入这一潜力巨大的市场。对这一新兴市场初期推出的是一种能够产生持续抗菌作用的擦手纸巾,这种产品已经拥有一项临时专利。 展开更多
关键词 cascades公司 智能纸 造纸工业 市场
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Influence of leading edge with real manufacturing error on aerodynamic performance of high subsonic compressor cascades 被引量:22
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作者 Chi MA Limin GAO +2 位作者 Haohao WANG Ruiyu LI Baohai WU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第6期220-232,共13页
To investigate the influence of real leading-edge manufacturing error on aerodynamic performance of high subsonic compressor blades,a family of leading-edge manufacturing error data were obtained from measured compres... To investigate the influence of real leading-edge manufacturing error on aerodynamic performance of high subsonic compressor blades,a family of leading-edge manufacturing error data were obtained from measured compressor cascades.Considering the limited samples,the leadingedge angle and leading-edge radius distribution forms were evaluated by Shapiro-Wilk test and quantile–quantile plot.Their statistical characteristics provided can be introduced to later related researches.The parameterization design method B-spline and Bezier are adopted to create geometry models with manufacturing error based on leading-edge angle and leading-edge radius.The influence of real manufacturing error is quantified and analyzed by self-developed non-intrusive polynomial chaos and Sobol’indices.The mechanism of leading-edge manufacturing error on aerodynamic performance is discussed.The results show that the total pressure loss coefficient is sensitive to the leading-edge manufacturing error compared with the static pressure ratio,especially at high incidence.Specifically,manufacturing error of the leading edge will influence the local flow acceleration and subsequently cause fluctuation of the downstream flow.The aerodynamic performance is sensitive to the manufacturing error of leading-edge radius at the design and negative incidences,while it is sensitive to the manufacturing error of leading-edge angle under the operation conditions with high incidences. 展开更多
关键词 Aerodynamic performance Compressor cascade Limited measurement data Manufacturing error Uncertainty analysis
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Blade bowing effects on radial equilibrium of inlet flow in axial compressor cascades 被引量:5
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作者 Han XU Hao CHANG +1 位作者 Donghai JIN Xingmin GUI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第5期1651-1659,共9页
The circumferentially averaged equation of the inlet flow radial equilibrium in axial compressor was deduced. It indicates that the blade inlet radial pressure gradient is closely related to the radial component of th... The circumferentially averaged equation of the inlet flow radial equilibrium in axial compressor was deduced. It indicates that the blade inlet radial pressure gradient is closely related to the radial component of the circumferential fluctuation(CF) source item. Several simplified cascades with/without aerodynamic loading were numerically studied to investigate the effects of blade bowing on the inlet flow radial equilibrium. A data reduction program was conducted to obtain the CF source from three-dimensional(3D) simulation results. Flow parameters at the passage inlet were focused on and each term in the radial equilibrium equation was discussed quantitatively. Results indicate that the inviscid blade force is the inducement of the inlet CF due to geometrical asymmetry. Blade bowing induces variation of the inlet CF, thus changes the radial pressure gradient and leads to flow migration before leading edge(LE) in the cascades. Positive bowing drives the inlet flow to migrate from end walls to mid-span and negative bowing turns it to the reverse direction to build a new equilibrium. In addition, comparative studies indicate that the inlet Mach number and blade loading can efficiently impact the effectiveness of blade bowing on radial equilibrium in compressor design. 展开更多
关键词 Axial compressor BOWING Cascade Circumferential fluctuation Inlet flow Radial equilibrium
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Cascades with coupled map lattices in preferential attachment community networks 被引量:6
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作者 崔迪 高自友 赵小梅 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1703-1708,共6页
In this paper, cascading failure is studied by coupled map lattice (CML) methods in preferential attachment community networks. It is found that external perturbation R is increasing with modularity Q growing by sim... In this paper, cascading failure is studied by coupled map lattice (CML) methods in preferential attachment community networks. It is found that external perturbation R is increasing with modularity Q growing by simulation. In particular, the large modularity Q can hold off the cascading failure dynamic process in community networks. Furthermore, different attack strategies also greatly affect the cascading failure dynamic process. It is particularly significant to control cascading failure process in real community networks. 展开更多
关键词 community networks MODULARITY coupled map lattices cascading failure
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Tolerance of edge cascades with coupled map lattices methods 被引量:7
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作者 崔迪 高自友 郑建风 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期992-996,共5页
This paper studies the cascading failure on random networks and scale-free networks by introducing the tolerance parameter of edge based on the coupled map lattices methods. The whole work focuses on investigating som... This paper studies the cascading failure on random networks and scale-free networks by introducing the tolerance parameter of edge based on the coupled map lattices methods. The whole work focuses on investigating some indices including the number of failed edges, dynamic edge tolerance capacity and the perturbation of edge. In general, it assumes that the perturbation is attributed to the normal distribution in adopted simulations. By investigating the effectiveness of edge tolerance in scale-free and random networks, it finds that the larger tolerance parameter λ can more efficiently delay the cascading failure process for scale-free networks than random networks. These results indicate that the cascading failure process can be effectively controlled by increasing the tolerance parameter λ. Moreover, the simulations also show that, larger variance of perturbation can easily trigger the cascading failures than the smaller one. This study may be useful for evaluating efficiency of whole traffic systems, and for alleviating cascading failure in such systems. 展开更多
关键词 cascading failures coupled map lattice methods TOLERANCE
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AN EFFICIENT METHOD FOR SOLVING THE MIXED DIRECT-INVERSE PROBLEM OF THE TRANSONIC ROTATIONAL FLOW IN PLANE CASCADES 被引量:1
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作者 Liu Qiusheng Shen Mengyu Ren Yuxin Qinghua University 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1989年第4期323-331,共9页
The method in [1] has been extended to the case of rotational flow in this paper. A new method for dealing with the shock wave is presented. This method has the advantages of both the shock-fitting and the shock captu... The method in [1] has been extended to the case of rotational flow in this paper. A new method for dealing with the shock wave is presented. This method has the advantages of both the shock-fitting and the shock capturing methods. The direct problem and the mixed direct-inverse prob- lem of the rotational flow in a transonic plane cascade at both design and off design conditions are solved, and the results show that the present method has rapid convergence rate and high accuracy even for the flow with moderately strong shocks. The calculations have been carried out on the DPS-8 computer, and for the direct problem, only 50-80 iterations are needed, and 50-80 seconds of CPU time are required. 展开更多
关键词 transonic flow cascade flow the rotational flow TURBOMACHINERY the mixed direct-inverse problem.
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