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Effects of Heat Transfer on Laminar-to-Turbulent Transition over a Compressor blade Operating at Low Reynolds Number

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Journal of Thermal Science 2024年第5期33卷 1826-1838页

作者： lu Lehan WANG Mingyang ZHANG Yanfeng SUN Shuang HUANG Zhen WANG Maomao Department of aviation Engineering Civil Aviation University of ChinaTianjin 300300China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Aerodynamics CARDCMianyang 621000China

To control the transition process in a laminar separation bubble(LSb)over an ultra-high load compressor blade at a Re of 1.5×10^(5),the effects of wall heat transfer were considered and numerically investigated by large eddy simulations(LES).Compared with the adiabatic wall condition,the local kinematic viscosity of airflow was reduced by wall cooling;thus the effects of turbulent dissipation on the growth of fluctuations were *** such,the transition occurred much earlier,and the size of LSb became *** the cooled surface,the spanwise vortices deformed much more rapidly and the size of hairpin vortex structures was ***,the rolling-up of 3D hairpin vortices and the ejection and sweeping process very close to the blade surface was ***,the aerodynamic losses of the compressor blade were reduced by 18.2%and 38.4%for the two cooled wall *** results demonstrated the feasibility of wall cooling in controlling the transition within an LSb and reducing the aerodynamic loss of an ultra-highly loaded compressor blade.

关键词： heat transfer compressor blade laminar-to-turbulent transition loss generation

Energy-saving design and optimization of pressure-swing-assisted ternary heterogenous azeotropic distillations

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Chinese Journal of Chemical Engineering 2024年第4期68卷 1-7页

作者： Lianjie Wu Kun lu Qirui Li Lianghua Xu Yiqing luo Xigang Yuan Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion College of Chemical and Chemical EngineeringTianjin University of TechnologyTianjin 300384China State Key Laboratory of Chemical Engineering Tianjin UniversityTianjin 300072China

A huge amount of energy is always consumed to separate the ternary azeotropic mixtures by *** heterogeneous azeotropic distillation and the pressure-swing distillation are two kinds of effective technologies to separate heterogeneous azeotropes without entrainer *** give better play to the synergistic energy-saving effect of these two processes,a novel pressure-swing-assisted ternary heterogeneous azeotropic distillation(THAD)process is proposed *** this process,the ternary heterogeneous azeotrope is decanted into two liquid phases before being refluxed into the azeotropic distillation column to avoid the aqueous phase remixing,and three columns'pressures are modified to decrease the flowrates of the recycle *** the dividing wall column and heat integration technologies are introduced to further reduce its energy consumption,and the pressureswing-assisted ternary heterogeneous azeotropic dividing-wall column and its heat integration structure are achieved.A genetic algorithm procedure is used to optimize the proposed *** design results show that the proposed processes have higher energy efficiencies and lower CO_(2)emissions than the published THAD process.

关键词： Distillation Separation Process control Process systems

Large reversible magnetocaloric effect in antiferromagnetic Er_(3)Si_(2)C_(2) compound

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Journal of Rare Earths 2024年第8期42卷 1555-1559,I0005页

作者： Hao Sun lu Tian Xinqiang Gao Zhaojun Mo Jun Shen baogen Shen School of Rare Earths University of Science and Technology of ChinaHefei230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China Department of Energy and Power Engineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China

The magnetic properties,magnetic phase transition and magnetocaloric effects(MCE) of Er_(3)Si_(2)C_(2) compound were investigated based on theoretical calculations and experimental *** on the first principles calculations,the antiferromagnetic(AFM) ground state type in Er_(3)Si_(2)C_(2) compound was predicted and its electronic structure was *** experimental results show that Ei_(3)Si_(2)C_(2) compound is an AFM compound with the Neel temperature(T_(N) of 7 K and undergoes a field-induced firstorder magnetic phase transition from AFM to ferromagnetic(FM) under magnetic fields exceeding 0.6 T at 2 *** magnetic transition process of Er_(3)Si_(2)C_(2) compound was investigated and *** values of the maximum magnetic entropy change(-ΔS_(M)^(max)) and the refrigeration capacity(RC) are 17 J/(kg·K)and 193 J/kg under changing magnetic fields of 0-5 T,*** a potential cryogenic magnetic refrigerant,the Er_(3)Si_(2)C_(2) compound also provides an interesting research medium to study the magnetic phase transition process.

关键词： Magnetic materials Magnetocaloric Metamagnetic transitions Magnetic phase transition Rare earths

A combined experimental and DEM investigation of grain interlocking in sheared granular assemblies

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Particuology 2024年第7期90卷 436-451页

作者： Rui lu Qiang luo Tengfei Wang David P.Connolly Tao Xie School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-Speed Railway Engineering(Southwest Jiaotong University) Ministry of EducationChengdu 610031China School of Civil Engineering University of LeedsLeeds LS29JTUK Department of Civil Engineering McMaster UniversityHamiltonONCanada

Compacted granular material,integral to geotechnical engineering,undergoes translation,rotation,and interlocking when subject to shear displacements or external *** present study focuses on the interlocking of heterogeneous granular materials,a complex behavior influenced by gradation,compaction,and varying particle geometry,and has consequently received limited attention in existing *** address this research gap,we conducted an analysis on the effect of grain interlocking on the shear resistance of granular assemblies,using a combination of laboratory testing and the discrete element method(DEM).Initially,large-scale direct shear tests were conducted on gravel−sand mixes with varying degrees of compaction and normal *** of the mixes also underwent subsequent shear reversal to explore the differences in grain interlocking between the two shearing processes on the shear *** analyzing the laboratory results,a mesoscopic scale investigation was performed by replicating the test using discrete element *** facilitate this,granular particle geometries were measured using 3D laser scanning based on the physical lab ***,based on these scans,discrete element R-block and ball models were utilized to construct both the coarse and fine particles within the *** vibro-compaction was employed to regulate the degree of *** results indicate that an increase in vertical pressure,coupled with a zero dilatancy angle,results in a rising stress ratio,indicative of grain *** interlocking exhibits a positive correlation with both the coarse content and the degree of compaction,and varies depending on the shear *** interlocking progresses,the shear band,induced by particle movement,expands and is associated with reduced particle rotation near the shear *** study further reveals a consistent positive correlation between interlocking and the principal orientation angle of strong normal c

关键词： Granular material Interlocking Shear resistance Direct shear Discrete element method Vibro-compaction

Progress in clinical diagnosis and treatment of colorectal cancer with rare genetic variants

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Cancer biology & Medicine 2024年第6期21卷 473-483页

作者： Shuyi Chen Jing Gu Kaichun Wu Xiaodi Zhao Yuanyuan lu State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers and National Clinical Research Center for Digestive Diseases Xijing Hospital of Digestive DiseasesFourth Military Medical UniversityXi’an 710032China School of basic Medical Sciences Fourth Military Medical UniversityXi’an 710032China

Targeted therapy is crucial for advanced colorectal cancer(CRC) positive for genetic drivers. With advances in deep sequencing technology and new targeted drugs, existing standard molecular pathological detection systems and therapeutic strategies can no longer meet the requirements for careful management of patients with advanced CRC. Thus, rare genetic variations require diagnosis and targeted therapy in clinical practice. Rare gene mutations, amplifications, and rearrangements are usually associated with poor prognosis and poor response to conventional therapy. This review summarizes the clinical diagnosis and treatment of rare genetic variations, in genes including erb-b2 receptor tyrosine kinase 2(ERbb2), b-Raf proto-oncogene, serine/threonine kinase(bRAF), ALK receptor tyrosine kinase/ROS proto-oncogene 1, receptor tyrosine kinase(ALK/ROS1), neurotrophic receptor tyrosine kinases(NTRKs), ret proto-oncogene(RET), fibroblast growth factor receptor 2(FGFR2), and epidermal growth factor receptor(EGFR), to enhance understanding and identify more accurate personalized treatments for patients with rare genetic variations.

关键词： Genetic variation gene mutation gene amplification gene rearrangement targeted therapy

A LESO based backstepping Controller Considering Coal Seam Hardness for Rotary Speed in Coal Mine Tunnel Drilling Process

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Journal of Systems Science & Complexity 2024年第5期37卷 1789-1808页

作者： CHEN luefeng LIU Xiao WU Min lu Chengda PEDRYCZ Witold HIROTA Kaoru School of Automation China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education Department of Electrical and Computer Engineering University of Alberta The Tokyo Institute of Technology

In the process of coal mine drilling, controlling the rotary speed is important as it determines the efficiency and safety of drilling. In this paper, a linear extended state observer(LESO) based backstepping controller for rotary speed is proposed, which can overcome the impact of changes in coal seam hardness on rotary speed. Firstly, the influence of coal seam hardness on the drilling rig's rotary system is considered for the first time, which is reflected in the numerical variation of load torque, and a dynamic model for the design of rotary speed controller is established. Then an LESO is designed to observe the load torque, and feedforward compensation is carried out to overcome the influence of coal seam hardness. based on the model of the compensated system, a backstepping method is used to design a controller to achieve tracking control of the rotary speed. Finally, the effectiveness of the controller designed in this paper is demonstrated through simulation and field experiments, the steady-state error of the rotary speed in field is 1 r/min, and the overshoot is reduced to 5.8%. This greatly improves the stability and security, which is exactly what the drilling process requires.

关键词： backstepping extended state observer hydraulic tunnel drilling machine rotary speed

Fast spreading of surface ozone in both temporal and spatial scale in Pearl River Delta

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Journal of Environmental Sciences 2024年第3期137卷 540-552页

作者： Tianhui Cao Haichao Wang Lei Li Xiao lu Yiming Liu Shaojia Fan School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary Key Laboratory of Tropical Atmosphere-Ocean SystemMinistry of EducationZhuhai 519082China

Surface ozone(O_(3))is a major air pollutant and draw increasing attention in the Pearl River Delta(PRD),***,we characterize the spatial-temporal variability of ozone based on a dataset obtained from 57 national monitoring sites during *** results show that:(1)the seasonal difference of ozone distribution in the inland and coastal areas was significant,which was largely affected by the wind pattern reversals related to the East Asian monsoon,and local ozone production and destruction;(2)the daily maximum 8hr average(MDA8 O_(3))showed an overall upward trend by 1.11 ppbv/*** the trends in the nine cities varied differently by ranging from-0.12 to 2.51 ppbv/*** hot spots of ozone were spreading to southwestern areas from the central areas since *** ozone is becoming a year-round air pollution problem with the pollution season extending to winter and spring in PRD region.(3)at the central and southwestern PRD cities,the percentage of exceedance days from the continuous type(defined as≥3 days)was ***,the ozone concentration of continuous type was much higher than that of scattered exceedance type(ber of exceedance days during the continuous type is *** results indicate that it is more difficult to eliminate the continuous exceedance than the scatter pollution days and highlight the great challenge in mitigation of O_(3)pollution in these cities.

关键词： Surface ozone pollution Ozone trend Spatial and temporal variability Pearl River Delta Pollution mitigation

Microstructures and micromechanical behaviors of high -entropy alloys investigated by synchrotron X-ray and neutron diffraction techniques: A review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1333-1349页

作者： Yubo Huang Ning Xu Huaile lu Yang Ren Shilei Li Yandong Wang beijing Advanced Innovation Center of Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China AnSteel beijing Research Institute Co.Ltd. Beijing 102200China Spallation Neutron Source Science Center Dongguan 523803China Department of Physics City University of Hong KongHong Kong 999077China Institute for Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and *** studies on the deformation mech-anisms of HEAs can guide microstructure control and toughness design,which is vital for understanding and studying state-of-the-art structural *** X-ray and neutron diffraction are necessary techniques for materials science research,especially for in situ coupling of physical/chemical fields and for resolving macro/microcrystallographic information on ***,several re-searchers have applied synchrotron X-ray and neutron diffraction methods to study the deformation mechanisms,phase transformations,stress behaviors,and in situ processes of HEAs,such as variable-temperature,high-pressure,and hydrogenation *** this review,the principles and development of synchrotron X-ray and neutron diffraction are presented,and their applications in the deformation mechanisms of HEAs are *** factors that influence the deformation mechanisms of HEAs are also *** review fo-cuses on the microstructures and micromechanical behaviors during tension/compression or creep/fatigue deformation and the application of synchrotron X-ray and neutron diffraction methods to the characterization of dislocations,stacking faults,twins,phases,and intergrain/interphase stress *** on future developments of synchrotron X-ray and neutron diffraction and on research directions on the deformation mechanisms of novel metals are discussed.

关键词： high-entropy alloys microstructures micromechanical behaviors synchrotron X-ray diffraction neutron diffraction

Controlling secondary flow in high-lift low-pressure turbine using boundary-layer slot suction

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Chinese Journal of Aeronautics 2024年第3期37卷 21-33页

作者： Xiao QU Liunan LI Yingjie ZHANG Xingen lu Junqiang ZHU Yanfeng ZHANG School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100190China

The design of high-lift Low-Pressure Turbines(LPTs)causes the separation of the boundary layer on the suction side of the blade and leads to a strong secondary *** present study aims to minimize secondary losses through endwall slot suction and incoming wakes in a front-loaded high-lift LPT cascade with Zweifel of 1.58 under low Reynolds number of *** slotted schemes for the boundary layer of the endwall were designed(Plan A and Plan b),and the effects of suction mass flow on secondary flow were *** underlying physics of the endwall boundary layer of the suction and secondary flow under unsteady wakes was *** results show that slot suction at the endwall boundary layer can significantly suppress the secondary flow by removing low-momentum *** A and b significantly reduced the secondary kinetic energy by 44.2%and 36.9%,respectively,compared with the baseline cascade at the suction mass flow ratios of 1%.With an increase in the mass flow ratio of suction,the secondary flow was gradually reduced in both Plans A and *** is more beneficial to control the secondary flow to destroy the intersection of the pressure side and suction side of the horseshoe vortex before it develops into a passage *** unsteady wakes,the combined effects of incoming wakes and endwall boundary layer suction can further suppress the secondary flow at the suction mass flow ratios of 2%for Plan A,because the positive and negative vorticity inside upstream wakes accelerated the mixing of the main flow and secondary flow and thus increased the energy of secondary vortices.

关键词： Low-pressure turbine Secondary flow Flow control boundary-layer suction Incoming wake