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Deep reinforcement learning based active surge control for aeroengine compressors

Chinese Journal of Aeronautics 2024年第7期37卷 418-438页

作者： Xinglong ZHANG Zhonglin LIN Runmin ji Tianhong ZHANG College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This study proposes an active surge control method based on deep reinforcement learning to ensure the stability of compressors when adhering to the pressure rise command across the wide operating range of an ***,the study establishes the compressor dynamic model with uncertainties,disturbances,and Close-Coupled Valve(CCV)actuator *** upon this foundation,a Partially Observable Markov Decision Process(POMDP)is defined to facilitate active surge *** address the issue of unobservability,a nonlinear state observer is designed using a finite-time high-order sliding ***,an Improved Soft Actor-Critic(ISAC)algorithm is developed,incorporating prioritized experience replay and adaptive temperature parameter techniques,to strike a balance between exploration and convergence during *** addition,reasonable observation variables,error-segmented reward functions,and random initialization of model parameters are employed to enhance the robustness and generalization ***,to assess the effectiveness of the proposed method,numerical simulations are conducted,and it is compared with the fuzzy adaptive backstepping method and Second-Order Sliding Mode Control(SOSMC)*** simulation results demonstrate that the deep reinforcement learning based controller outperforms other methods in both tracking accuracy and ***,the proposed active surge controller can effectively ensure stable operation of compressors in the high-pressure-ratio and high-efficiency region.

关键词： Aeroengine surge Active surge control Moore-Greitzer model Deep reinforcement learning Soft actor-critic Nonlinear observer

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Experimental and numerical investigation of two blended blade and endwall configurations

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Chinese Journal of Aeronautics 2024年第9期37卷 150-163页

作者： Tongtong MENG Xin LI Ling ZHOU Lucheng ji Institute for Aero Engine Tsinghua UniversityBeijing 100084China Schoolof Aerospace Engineering Bejing Institute of TechnologyBeijing 0081China

The Blended Blade and Endwall(BBEW)technique has proven to be effective in control-ling the intersection of boundary layer in corner region of the compressor *** this study,the experiment and analysis of two different BBEW designs are ***,based on a linear cas-cade with 0.7 Mach number inflow,two different configurations,BBEW 1 and BBEW 2,are well ***,according to the experimental result,control effects of these two BBEW configu-rations are validated and compared subsequently under various working *** results demonstrate a reduction in total pressure loss of 12.8%and 29%at the design point for BBEW 1 and BBEW 2,***,the BBEW technique proves effective in suppressing the development of the boundary layer and preventing corner *** by detailed numerical analysis,improvements around the corner region,especially for the boundary layer,are extracted to show the mechanisms and distinctions between the two *** results indicate that BBEW 1 significantly restrains the development of boundary layer before separation occurs,while BBEW 2 directly controls the strength and scale of the corner separation.

关键词： Aerodynamic Computational fluid dynamic Experiment Corner separation Blended Blade and Endwall(BBEW)

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3D coarse-grained DPM simulation of the MIP reaction-regeneration loop

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Particuology 2024年第6期89卷 57-66页

作者： Yanhao Ye Shuai Zhang ji Xu Wei Ge State Key Laboratory of Mesoscience and Engineering(formerly State Key Laboratory of Multiphase Complex Systems) Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

The reactor-regenerator loop is the core facility of the maximizing iso-paraffin(MIP)*** the discrete particle method(DPM)simulation can provide detailed information at the particle scale,it has been unable to simulate such a complex loop system due to limitations of coarse-grained(CG)models,computing software,and *** this study,a newly proposed soft-shell CG-DPM model with a CG ratio of up to 800 is used to simulate a 3.5 Mt/a industrial-scale MIP reactor-regenerator *** solid fraction distribution obtained is found to agree well with in-situ *** properties including the distribution of solid fraction,gas and solid velocity,standard derivation of solid fraction with time,temporal distribution of the flow field,and particle residence time distribution are measured in the simulation,which are meaningful to better design and operate such systems in the future.

关键词： Discrete particle method Coarse-grain Maximizing iso-paraffins Full-loop Reaction-regeneration system

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Anisotropic Mechanical Response of Nacre to Heat Treatment Under Indentation:Effect of Structural Orientation

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Journal of Bionic Engineering 2024年第3期21卷 1453-1464页

作者： Simin Liang Yingying Li Hongmei ji Xiaowu Li Department of Materials Physics and Chemistry School of Materials Science and EngineeringKey Laboratory for Anisotropy and Texture of MaterialsMinistry of EducationNortheastern UniversityShenyang110819China

It is generally considered that heat treatments have a negative impact on the mechanical properties of nacre due to thermal decomposition of the organic ***,the present work investigated the microindentation behavior on fresh and heat-treated nacres from two orthogonal directions,and the results demonstrate that both hardness value and damage tolerance can remain almost unchanged on the cross-section with the organic matrix degeneration,despite a significant deterioration on the platelet *** analyses suggest that the anisotropic response of indentation behavior to heat treatment in nacre is primarily caused by its structural ***,compared with a single layer of irregular interplatelet interfaces in cross-sectional specimens,the multiple layers of parallel interlamellar interfaces in in-plane specimens exhibit a much greater ability to impede indenter-triggered destruction,and heat treatments would reduce the in-plane hardness but nearly have no effect on the cross-sectional ***,the deeper embedding of platelets in cross-sectional specimens enhances their resistance to interface cracking caused by organic matrix degradation at high temperatures,leading to a reduced sensitivity to ***,the indentation behavior of nacre shows different tendencies in response to variations in the organic matrix state along normal and parallel directions.

关键词： Nacre Structural orientation Heat treatment Indentation behavior Organic matrix

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Compound Product of Hypermatrices

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Journal of Systems Science & Complexity 2024年第1期37卷 169-183页

作者： CHENG Daizhan MENG Min ZHANG Xiao ji Zhengping Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Control Science and Engineering School of Electronics and Information EngineeringTongji UniversityShanghai 201210China National Center for Mathematics and Interdisciplinary Sciences Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100149China.

The semi-tensor product(STP)of matrices is generalized to multidimensional arrays,called the compound product of *** product is first defined for three-dimensional hypermatrices with compatible orders and then extended to general *** different types of hyperdeterminants are introduced and certain properties are *** Lie groups and Lie algebras corresponding to the hypermatrix products are ***,these results are applied to dynamical systems.

关键词： Compound semi-tensor product hyperdeterminants hypereigenvalues and hypereigenvectors hypergeneral linear groups hypermatrices.

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Forced boiling of nonazeotropic immiscible mixture in a supercapillary microchannel array for ultra-high heat flux removal with chip junction temperature below 85℃

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Science China(Technological Sciences) 2024年第5期67卷 1364-1380页

作者： SUN Bo BAO YuChen TIAN Tong LI ji School of Engineering Science University of Chinese Academy of SciencesBeijing100049China Laboratory of Advanced Thermal Management Technologies School of Engineering ScienceUniversity of Chinese Academy of SciencesBeijing100049China

In this study,a structure-optimized two-phase microchannel heat sink with sintered submicron nucleation sites was developed and *** copper-based microchannels had a rectangular cross-section with an equivalent hydraulic diameter of 222μ*** subcooled flow boiling characteristics were comprehensively compared between pure HFE-7100 and a non-azeotropic,immiscible binary mixture of HFE-7100 and water,considering heating areas of 1 and 5 cm^(2).The total heating power input to the test section were 100–1500 and 250–3000 W for a 1 and 5 cm^(2)heat source,respectively,with a flow rate ranging from 50 to150 L/*** to pure HFE-7100,the non-azeotropic immiscible binary mixture of HFE-7100/water in the sintered porous microchannels exhibited a much higher overall heat transfer coefficient and lower power *** maintain the junction temperature of a high power electronic chip below 85℃,the proposed supercapillary microchannel heat sink could effectively dissipate the heat flux of 1275 W/cm^(2)over 1 cm^(2)heat source and 500 W/cm^(2)over 5 cm^(2)heat *** addition,the volume ratio of the binary mixture strongly influence the two-phase flow heat transfer *** optimal volume ratio exist in terms of the thermal resistance–pumping power minimization(HFE-7100:water=2:8 is recommended in this study).The findings of this investigation on the flow boiling properties of non-azeotropic immiscible mixtures help fill a gap in the related field.

关键词： microchannel sintered powder coating submicron nucleation cavities nonazeotropic immiscible ultra-high heat flux

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Gas–solid reactor optimization based on EMMS-DPM simulation and machine learning

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Particuology 2024年第6期89卷 131-143页

作者： Haolei Zhang Aiqi Zhu ji Xu Wei Ge State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China

Design,scaling-up,and optimization of industrial reactors mainly depend on step-by-step experiments and engineering experience,which is usually time-consuming,high cost,and high *** numerical simulation can reproduce high resolution details of hydrodynamics,thermal transfer,and reaction process in reactors,it is still challenging for industrial reactors due to huge computational *** this study,by combining the numerical simulation and artificial intelligence(AI)technology of machine learning(ML),a method is proposed to efficiently predict and optimize the performance of industrial reactors.A gas–solid fluidization reactor for the methanol to olefins process is taken as an example.1500 cases under different conditions are simulated by the coarse-grain discrete particle method based on the Energy-Minimization Multi-Scale model,and thus,the reactor performance data set is *** develop an efficient reactor performance prediction model influenced by multiple factors,the ML method is established including the ensemble learning strategy and automatic hyperparameter optimization technique,which has better performance than the methods based on the artificial neural ***,the operating conditions for highest yield of ethylene and propylene or lowest pressure drop are searched with the particle swarm optimization algorithm due to its strength to solve non-linear optimization *** show that decreasing the methanol inflow rate and increasing the catalyst inventory can maximize the yield,while decreasing methanol the inflow rate and reducing the catalyst inventory can minimize the pressure *** two objectives are thus conflicting,and the practical operations need to be compromised under different circumstance.

关键词： Discrete particle method Artificial intelligence Machine learning Particle swarm optimization Industrial reactor optimization

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Effect of Air Distribution on the Transport Characteristics of Solid Particles in the Thermal Storage and Release System of Circulating Fluidized Bed

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Journal of Thermal Science 2024年第4期33卷 1554-1563页

作者： ji Zengcai SONG Guoliang TANG Zihua SUN Liwei State Key Laboratory of Coal Conversion Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Dalian National Laboratory for Clean Energy Dalian116023China

Solid particle heat storage technology offers a potential solution to the challenges posed by the significant growth of renewable energy sources,particularly in terms of grid security and ***,it has the capability to optimize the energy utilization efficiency of the power *** order to investigate the transport regulation characteristics of solid particles in the thermal storage and release system of a circulating fluidized bed(CFB),a test rig with a capacity of 0.1 MW(th)was *** rig was utilized to systematically study the transport regulation characteristics of solid particles under the double U-type valve feed structure and U-type valve discharge *** experimental findings indicate that the system's design enables efficient and rapid storage and release of solid particles in the *** air distribution mode,specifically the double U-type valve feed structure and the U-type valve discharge structure,significantly influence the feed and discharge characteristics of the ash storage *** was observed that the impact of loose air on these characteristics is more substantial than that of the return air,irrespective of the feed structure or the return *** adjusting the feed and discharge rate,it is recommended to adopt a scheme that involves coarse adjustment through loose air and fine adjustment through return air.

关键词： solid particle thermal storage air distribution mode transport regulation

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Enhancing Low-Frequency Microwave Absorption Through Structural Polarization Modulation of MXenes

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Nano-Micro Letters 2024年第10期16卷 435-452页

作者： Bo Shan Yang Wang Xinyi ji Yi Huang College of Light Industry Science and Engineering State Key Laboratory of Biobased Fiber Manufacturing TechnologyTianjin University of Science and TechnologyTianjin 300457People's Republic of China National Institute for Advanced Materials Tianjin Key Laboratory of Metal and Molecule Based Material ChemistryKey Laboratory of Functional Polymer MaterialsCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)School of Materials Science and EngineeringNankai UniversityTianjin 300350People's Republic of China

Two-dimensional carbon-based materials have shown promising electromagnetic wave absorption capabilities in mid-and high-frequency ranges,but face challenges in low-frequency absorption due to limited control over polarization response mecha-nisms and ambiguous resonance *** this study,we pro-pose a novel approach to enhance absorption efficiency in aligned three-dimensional(3D)MXene/CNF(cellulose nanofibers)cavities by modifying polarization properties and manipulating resonance response in the 3D MXene *** controlled polarization mechanism results in a significant shift of the main absorption region from the X-band to the S-band,leading to a remarkable reflection loss value of-47.9 dB in the low-frequency ***,our findings revealed the importance of the oriented electromagnetic coupling in influencing electromagnetic response and microwave absorption *** present study inspired us to develop a generic strategy for low-frequency tuned absorption in the absence of magnetic element participation,while orientation-induced polarization and the derived magnetic resonance coupling are the key controlling factors of the method.

关键词： Hierarchical structure MXene Microwave absorption Low-frequency

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Boeravinone B ameliorates allergic nasal inflammation by modulating the GATA-3/T-bet signaling pathway in a mouse model of allergic rhinitis

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Asian Pacific Journal of Tropical Biomedicine 2024年第6期14卷 245-252页

作者： Ben Ye ji-Zhe Wang Department of Otorhinolaryngology Second Hospital of Dalian Medical UniversityDalian116000China Department of Otorhinolaryngology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan250000China

Objective:To evaluate the anti-allergic effect of boeravinone B against ovalbumin-induced allergic rhinitis in mice and explore its possible ***:For the induction of allergic rhinitis,mice were intraperitoneally sensitized and intranasally challenged with ovalbumin,as well as orally received various concentrations of boeravinone *** mucosal inflammation,and the levels of nitric oxide,β-hexosaminidase,IFN-γ,LTC-4,myeloperoxidase,Nrf2,HO-1,GATA-3,ROR-γ,T-bet,antioxidant parameters,and allergen-specific cytokines were ***:Boeravinone B markedly reduced ovalbumin-induced increase in the number of episodes of nasal sneezing,rubbing,and discharge,as well as the levels of IgE,IgG1,andβ-hexosaminidase(P<0.05).It also significantly reduced differential cell count,myeloperoxidase,oxide-nitrosative stress,and the levels of IL-1β,IL-4,IL-5,IL-6,IL-13,IL-17,tumor necrosis factor-α,GATA-3,and ROR-γwhile enhancing the level of ***:Boeravinone B is a potential therapeutic agent for allergic rhinitis by modulating various inflammatory mediators and immune responses.

关键词： Allergic reaction Boeravinone B Oxidative stress Inflammation Ovalbumin

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