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Theoretical and experimental studies of gas preparation system for pressurization and reactive control system of launch vehicle

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Chinese Journal of Aeronautics 2024年第7期37卷 168-177页

作者： Valeriy TRUSHLYAKOV Vladislav URBANSKY Vadim YUDINTSEV Department of Aviation and Rocket Building Omsk State Technical UniversityOmsk 644050Russia

A new gas preparation system(GasPS-RCS)is proposed to solve two tasks:(A)to heat helium gas for tank pressurization;(B)to prepare gas for the Launch Vehicle(LV)Reactive Control System(RCS)at the LV orientation and stabilization sections of the LV on passive parts of the flight trajectory,to provide conditions for launching the Liquid Rocket Engine(LRE).The system includes a gas generator based on hydrogen peroxide,a separator for water separation,heat exchangers independent of the LRE,and gas-jet *** proposed new system allowed to reduce the length of pressurizing gas lines and reduce the increased helium gas consumption during the heat exchanger warm-up interval of the LRE during its launch.A special advantage of the proposed system is the possibility of ground testing of heat exchangers without an operating LRE.A mathematical model based on the first law of thermodynamics was used to perform a comparative analysis of GasPS-RCS with traditional pressurization and RCS *** validate the mathematical model,the experimental studies of helium pressurizing of a liquid nitrogen tank were *** results show that the deviation of experimental and calculated values for pressure is 1.1%and for temperature up to 2%.According to the results of comparative analysis,the GasPS-RCS is 259 kg lighter for the first stage and 80 kg lighter for the second stage of the LV.

关键词： Engine restart Reactive control system Tank pressurization Cryogenics Hydrogen peroxide Heat exchanger

On-Chip Micro Temperature Controllers Based on Freestanding Thermoelectric Nano Films for Low-Power Electronics

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Nano-Micro Letters 2024年第7期16卷 98-108页

作者： Qun Jin Tianxiao Guo Nicolas Perez Nianjun Yang Xin Jiang Kornelius Nielsch Heiko Reith Institute for Metallic Materials Leibniz Institute for Solid State and Materials Research01069 DresdenGermany Institute of Materials Engineering University of Siegen57076 SiegenGermany Institute of Applied Physics Technical University of Dresden01069 DresdenGermany Institute of Materials Science Technical University of Dresden01069 DresdenGermany

Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern ***,this inevitably exac-erbates the inhomogeneity of temperature distribution in microsystems,making precise temperature control for electronic components extremely ***,we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50×50μm^(2),which are fabricated from dense and flat freestanding Bi2Te3-based ther-moelectric nano films deposited on a newly developed nano graphene oxide membrane *** tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics.A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445μW,resulting in an ultrahigh temperature control capability over 100 K mW^(-1).Moreover,an ultra-fast cooling rate exceeding 2000 K s^(-1) and excellent reliability of up to 1 million cycles are *** proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics.

关键词： Temperature control Low-power electronics On-chip micro temperature controller Freestanding thermoelectric nano films Temperature-sensitive components

Method for passivation of propellant residues in orbital stage tank of launch vehicle

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Chinese Journal of Aeronautics 2024年第1期37卷 64-76页

作者： Valeriy TRUSHLYAKOV Ivan LESNYAK Alexey PANICHKIN Department of Aviation and Rocket Building Omsk State Technical UniversityOmsk 644050Russia Sobolev Institute of Mathematics of the Siberian Branch of Russian Academy of Sciences Novosibirsk 630090Russia

The problem of removing unused liquid propellant residues from the tanks of spent spacecraft and orbital stages of Launch Vehicles(LV)leads to their explosion and the formation of space debris in *** provide a solution to this problem,a method for removing liquid propellant residues from the LV tanks after the mission completion is *** method is based on the gasification of liquid propellant residues in the tanks under acoustic-vacuum exposure and the discharge of the gasification products into the surrounding outer *** investigations were carried out on a Ground-based Experimental Installation(GEI)to determine the coefficient of heat transfer from the surface of an acoustic radiator to a *** obtained coefficient was then used to calculate the energy costs for the gasification of *** estimates are given on the example of the tank with kerosene residues from a spent second stage of the LV“Soyuz-2.1 v”.The optimal discharge rate at which kerosene does not freeze is 0.14 m^(3)/***,the acoustic exposure leads to an increase in the mass of evaporated kerosene over a given time by96.1%,and the energy costs are 1756.7 kJ(approximately 50% of the remaining electrical energy).

关键词： Propellant Weightlessness Liquid evaporation Heat and mass transfer Acoustics Vacuum Vapor bubbles

An Underwater Biomimetic Robot that can Swim,Bipedal Walk and Grasp

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Journal of Bionic Engineering 2024年第3期21卷 1223-1237页

作者： Qiuxuan Wu Liwei Pan FuLin Du ZhaoSheng Wu XiaoNi Chi FaRong Gao Jian Wang Anton A.Zhilenkov School of Automation Hangzhou Dianzi UniversityHangzhou310018China International Joint Research Laboratory for Autonomous Robotic Systems Hangzhou310018China GEELY Automotive Institute Hangzhou Vocational and Technical CollegeHangzhou310018China Institute of Hydrodynamics and Control Processes Sankt-Petersburg Saint Petersburg State Marine Technical UniversitySankt-PetersburgRussia

In developing and exploring extreme and harsh underwater environments,underwater robots can effectively replace humans to complete *** meet the requirements of underwater flexible motion and comprehensive subsea operation,a novel octopus-inspired robot with eight soft limbs was designed and *** robot possesses the capabilities of underwater bipedal walking,multi-arm swimming,and grasping *** closely interact with the underwater seabed environment and minimize disturbance,the robot employs a cable-driven flexible arm for its walking in underwater floor through a bipedal walking *** multi-arm swimming offers a means of three-dimensional spatial movement,allowing the robot to swiftly explore and navigate over large areas,thereby enhancing its ***,the robot’s walking arm enables it to grasp and transport objects underwater,thereby enhancing its practicality in underwater environments.A simplified motion models and gait generation strategies were proposed for two modes of robot locomotion:swimming and walking,inspired by the movement characteristics of octopus-inspired multi-arm swimming and bipedal *** experimental verification,the robot’s average speed of underwater bipedal walking reaches 7.26 cm/s,while the horizontal movement speed for multi-arm swimming is 8.6 cm/s.

关键词： Underwater soft robots Underwater bipedal walking Multi-arm swimming Cable drive

Determination of Thermal Properties of Unsmooth Si Nanowires

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Chinese Physics Letters 2024年第1期41卷 51-56页

作者：刘世贤 Alexander A.Barinov 訚菲 Vladimir I.Khvesyuk Department of Thermophysics Bauman Moscow State Technical UniversityMoscow 105005Russian Federation

We estimate the thermal properties of unsmooth Si nanowires,considering key factors such as size(diameter),surface texture(roughness)and quantum size effects(phonon states)at different *** nanowires with a diameter of less than 20 nm,we highlight the importance of quantum size effects in heat capacity calculations,using dispersion relations derived from the modified frequency equation for the elasticity of a *** thermal conductivities of nanowires with diameters of 37,56,and 115nm are predicted using the Fuchs–Sondheimer model and Soffer’s specular ***,the roughness parameters are chosen to reflect the technological characteristics of the real *** findings reveal that surface texture plays a significant role in thermal conductivity,particularly in the realm of ballistic heat transfer within *** study provides practical recommendations for developing new thermal management materials.

关键词： nanowires roughness size

Performance and enhanced oil recovery efficiency of an acid-resistant polymer microspheres of anti-CO2 channeling in low-permeability reservoirs

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Petroleum Science 2024年第4期21卷 2420-2432页

作者： Hai-Zhuang Jiang Hong-Bin Yang Ruo-Sheng Pan Zhen-Yu Ren Wan-Li Kang Jun-Yi Zhang Shi-Long Pan Bauyrzhan Sarsenbekuly state Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) Oil and Gas Engineering Research Institute School of Energy and Petroleum Industry Kazakh-British Technical University

CO2flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs,However,micro-fractures are developed in low-permeability reservoirs,which are essential oil flow channels but can also cause severe CO2gas channeling ***,anti-gas channeling is a necessary measure to improve the effect of *** kind of anti-gas channeling refers to the plugging of fractures in the deep formation to prevent CO2gas channeling,which is different from the wellbore *** microspheres have the characteristics of controllable deep plugging,which can achieve the profile control of low-permeability fractured *** acidic environments with supercritical CO2,traditional polymer microspheres have poor expandability and plugging *** on previous work,a systematic evaluation of the expansion performance,dispersion rheological properties,stability,deep migration,anti-CO2channeling and enhanced oil recovery ability of a novel acid-resistant polymer microsphere（DCNPM-A） was carried out under CQ oilifield conditions（salinity of85,000 mg/L,80℃,pH=3）.The results show that the DCNPM-A microsphere had a better expansion performance than the traditional microsphere,with a swelling rate of *** microsphere dispersion with a concentration of 0.1%-0.5% had the advantages of low viscosity,high dispersion and good injectability in the low permeability fractured *** the acidic environment of supercritical CO2,DCNPM-A microspheres showed excellent stability and could maintain strength for over 60 d with less *** core experiments,DCNPM-A microspheres exhibited delayed swelling characteristics and could effectively plug deep *** a plugging rate of 95%,the subsequent enhanced oil recovery of CO2flooding could reach 21.03%.The experimental results can provide a theoretical basis for anti-CO2channeling and enhanced oil recovery in low-permeability fractured reservoirs.

关键词： Low-permeability reservoir Anti-CO 2 channeling Polymer microsphere Acid resistance

An Integrated External Archive Local Disturbance Mechanism for Multi-Objective Snake Optimizer

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Chinese Journal of Electronics 2024年第4期33卷 989-996页

作者： Leifu GAO Zheng LIU Institute for Optimization and Decision Analytics Liaoning Technical University

It is an interesting research direction to develop new multi-objective optimization algorithms based on meta-heuristics. Both the convergence accuracy and population diversity of existing methods are not *** paper proposes an integrated external archive local disturbance mechanism for multi-objective snake optimizer(IMOSO) to overcome the above shortcomings. There are two improved strategies. The adaptive mating between subpopulations strategy introduces the special mating behavior of snakes with multiple husbands and wives into the original snake optimizer. Some positions are updated according to the dominated relationships between the newly created individuals and the original individuals. The external archive local disturbance mechanism is used to re-search partial non-inferior solutions with poor diversities. The perturbed solutions are non-dominated sorting with the generated solutions by the next iteration to update the next external archive. The main purpose of this mechanism is to make full use of the non-inferior solution information to better guide the population evolution. The comparison results of the IMOSO and 7 state-of-the-art algorithms on WFG benchmark functions show that IMOSO has better convergence and population diversity.

关键词： Accuracy Sociology Metaheuristics Diversity methods Benchmark testing Statistics Convergence

High-Energy Tunable 6.5-12 μm Picosecond Mid-Infrared Radiation Generated from Optical Parametric Amplifier Based on LiInSe_(2) Crystal

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激光与光电子学进展 2024年第13期61卷 457-462页

作者： Zhang Jingjing Wang Shilei Yang Feng Wang Shanpeng Gao Hongwei Bo Yong Cui Dafu Tao Xutang Peng Qinjun Key Lab of Solid state Laser Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China university of Chinese Academy of Sciences Beijing 100049China state Key Laboratory of Crystal Materials Shandong UniversityJinan 250100ShandongChina

We report high-energy tunable 6.5-12 μm ps mid-infrared radiation generation based on OPA pumped using 1064 nm laser in LISe *** simulated the relationship between the idler energy and crystal *** optimum LISe length of 4 mm was used to enhance the idler energy *** a pump energy of ~9.4 mJ, energy levels of ~146 and of ~27 μJ are generated at 6.5 μm and 12 μm, *** highest energy of ~205 μJ is achieved at 8.1 μm at a pump energy of ~19 ***, the angular and spectral width acceptance are measured.

关键词： tunable mid-infrared radiation nonlinear optical crystal LiInSe2 crystal optical parametric amplifier

Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： V.A.KRUPIN M.R.NURGALIEV A.R.NEMETS I.A.ZEMTSOV S.D.SUNTSOV T.B.MYALTON D.S.SERGEEV N.A.SOLOVEV D.V.SARYCHEV D.V.RYJAKOV S.N.TUGARINOV N.N.NAUMENKO National Research Centre“Kurchatov Institute” Moscow 123182Russia Bauman Moscow state technical university Moscow 105005Russia Institution“Project Center ITER” Moscow 123098Russia JSC“SOLAR” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECRH regimes. Discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport