检索结果-南通市图书馆

An Icy Worlds life detection strategy based on Exo-AUV

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第11期67卷 3515-3535页

作者： Bin WANG Hongde QIN National Key Laboratory of Autonomous Marine Vehicle Technology Harbin Engineering University shipbuilding {1. College Harbin Engineering University

In the solar system, Icy Worlds such as Europa and Enceladus hold great potential for extraterrestrial life and may provide humanity an answer, within this century, to the age-old question of life beyond Earth. Exo-AUV technology shows promise in life detection in the icy shell, at the ice-water interface and on the seafloor of exo-ocean. Space agencies, including NASA and DLR, are enthusiastic about deploying Exo-AUVs to explore life in these regions. However, the where and how to find life, the technologies to be utilized and the goals to be achieved are crucial aspects for future Exo-AUV life detection missions on Icy Worlds. This study delves into a hypothetical mission of life detection on Europa, discussing science goals,detectable objects, potential regions and biogenic analysis for Icy Worlds. It proposes a life detection strategy for Icy Worlds based on Exo-AUVs, presents key contextual elements for Exo-AUV operations, outlines technological requirements for hull,payloads and autonomy, introduces the current state of Exo-AUV research and addresses existing challenges. This study also suggests a roadmap for conceptual development of Exo-AUV and a Concept of Operations for Multiple Exo-AUV System(ConOps for MEAS). This system aims to assist planetary scientists and astrobiologists in exploring Icy Worlds, identifying robust biosignatures and potentially discovering extant organisms, even prebiotic chemical systems.

关键词： Icy Worlds Europa Life detection Biological potential Exo-AUV

Numerical Investigation of the Angle of Attack Effect on Cloud Cavitation Flow around a Clark-Y Hydrofoil

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in engineering & Sciences 2024年第6期139卷 2947-2964页

作者： Di Peng Guoqing Chen Jiale Yan Shiping Wang College of engineering Peking UniversityBeijing100871China College of shipbuilding {1. Harbin Engineering UniversityHarbin150001China

Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater *** re-entrant jet and compression wave resulting from the collapse of cavity vapour are pivotal factors contributing to cavity ***,these phenomena significantly modulate the evolution of cavitation *** this paper,numerical investigations into cloud cavitation over a Clark-Y hydrofoil were conducted,utilizing the Large Eddy Simulation(LES)turbulence model and the Volume of Fluid(VOF)method within the OpenFOAM *** analysis of results obtained at different angles of attack is undertaken.A discernible augmentation in cavity thickness is observed concomitant with the escalation in attack angle,alongside a progressive intensification in pressure at the leading edge of the hydrofoil,contributing to the suction *** results can serve as a fundamental point of reference for gaining a deeper comprehension of cloud cavitation dynamics.

关键词： Cloud cavitation re-entrant jet compression wave clark-Y hydrofoil

Dynamic Setting Method of Assessment Indicators for Power Curves of Renewable Energy Sources Considering Scarcity of Reserve Resources

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 101-114页

作者： Minghao Cao Jilai Yu the Department of Electrical engineering Harbin Institute of TechnologyHarbinChina

With the increasing proportion of renewable energy sources(RESs)in power grid,the reserve resource(RR)scarcity for correcting power deviation of RESs has become a potential ***,the power curve of RES needs to be more rigorously *** RR scarcity varies during different time periods,so the values of assessment indicators should be dynamically *** assessment indicators in this paper include two aspects,i.e.,deviation exemption ratio and penalty ***,this paper proposes a method for dynamically calculating the supply capacity and RR cost,primarily taking into account the operating status of thermal units,forecast information of RES,and load ***,after clarifying the logical relationship between the degree of RR scarcity and the values of assessment indicators,this paper establishes a mapping function between *** on this mapping function,a dynamic setting method for assessment indicators is *** the future,RES will generally be equipped with battery energy storage systems(BESSs).Reasonably utilizing BESSs to reduce the power deviation of RESs can increase the expected income of ***,this paper proposes a power curve optimization strategy for RESs considering self-owned *** case study demonstrates that the dynamic setting method of assessment indicators can increase the revenue of RESs while ensuring that the penalty fees paid by RESs to the grid are sufficient to cover the RR ***,the power curve optimization strategy can help RESs further increase income and fully utilize BESSs to reduce power deviation.

关键词： Renewable energy battery energy storage system(BESS) power curve assessment reserve service parameter setting

A compact bimorph rotary piezoelectric actuator with customized small power supply

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第4期67卷 1185-1195页

作者： DENG Jie LIU DaQing WANG WeiYi LIU YingXiang School of Mechatronics and engineering Harbin Institute of TechnologyHarbin 150001China

Inertial piezoelectric actuators are widely applied in precision devices with simple structure and accurate ***,existing inertial piezoelectric actuators still face the challenges of rollback motion and bulky power *** this work,an alternate excitation strategy and a customized small power supply for a bimorph rotary piezoelectric actuator(BRPA)are proposed to solve the *** BRPA prototype is designed with a bipedal symmetrical structure,measuring 35 mm in height and 32 mm in diameter,which has a maximum rotation velocity of 0.247 rad/s and a resolution of 0.66μ*** to the bipedal symmetrical structure,the friction directions between the driving feet and the rotor can be coordinated to suppress the *** rollback ratio is almost zero when the phase difference of the exciting signal is set as 1.0°.The customized power supply is designed and manufactured,whose size is 58 mm×56 mm×46 *** can output signals for the single step mode and the continuous mode,and they are adopted to excite BRPA to achieve a small stroke with one single step and a large stroke with continuous step,***,an experimental system for optical fiber alignment is developed based on the BRPA and the customized small power supply,the experiment has verified the practicability of this work in the precision fields,especially in the miniaturized precision systems.

关键词： inertial piezoelectric actuator customized small power supply single step mode continuous mode rollback suppression miniaturized precision system

Bio-inspired Attachment Mechanism of Dynastes Hercules:Vertical Climbing for On-Orbit Assembly Legged Robots

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic engineering 2024年第1期21卷 137-148页

作者： Yuetian Shi Xuyan Hou Zhonglai Na Jie Zhou Nan Yu Song Liu Linbo Xin Guowei Gao Yuhui Liu School of Mechatronics engineering Harbin Institute of TechnologyHarbin 150001China

With the increasing size of space facilities,on-orbit assembly requires robots to move on different heights of *** paper proposes a bio-inspired attachment mechanism for robot feet to enable climbing on different heights of *** by the attachment and grasping abilities of Dynastes Hercules,we utilize its foot microstructures,such as microhooks and setae,to achieve efficient contact and firm grip with the *** morphology and arrangement of these structures can inspire the design of robot feet to improve their grasping and stability *** study the biological structure of Dynastes Hercules,design and optimize the bio-inspired structure,analyze the influence of various factors from theoretical and experimental perspectives,and verify the feasibility of the scheme through *** propose an ideal climbing strategy that provides useful reference for robot applications in ***,the influence laws of various factors in this paper can be applied to robot foot design to improve their operation ability and stability performance in the space *** bio-inspired mechanism can improve robot working range and efficiency,which is critical for on-orbit assemblyin space.

关键词： Space assembly robot Truss climbing Bionic structure Dynastes Hercules tarsus

A self-powered solar-blind UV-enhanced Bi_(2)Se_(3)/a-Ga_(2)O_(3)/p-Si heterojunction photodetector for full spectral photoresponse and imaging

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第4期17卷 2960-2970页

作者： Yajie Han Shujie Jiao Jiangcheng Jing Lei Chen Ping Rong Shuai Ren Dongbo Wang Shiyong Gao Jinzhong Wang School of Materials Science and engineering Harbin Institute of TechnologyHarbin 150001China

Self-powered full-spectrum photodetectors(PDs)offer numerous advantages,such as broad application fields,high precision,efficiency,and multi-functionality,which represent a highly promising and potentially valuable class of detectors for future ***,insensitive response to solar-blind ultraviolet(UV)and complex and expensive preparation processes greatly limit their performance and practical *** this study,a self-powered full-spectrum Bi_(2)Se_(3)/a-Ga_(2)O_(3)/p-Si heterojunction PD with high sensitivity for solar-blind UV band prepared by a simple and low-cost two-step synthesis method is *** results reveal that the developed PD has an excellent performance,such as high sensitivity from 200 to 850 nm,and a responsivity of 1.38 mA/W as well as a detectivity of 3.22×1.^(1.) Jones under 254 nm light at zero ***,the unencapsulated device displays exceptional stability and imaging *** is expected that Bi_(2)Se_(3)/a-Ga_(2)O_(3)/p-Si heterojunction PD with a simple and low-cost synthesis method has great potential for self-powered full-spectrum photodetectors.

关键词： Bi_(2)Se_(3)/a-Ga_(2)O_(3)/p-Si self-powered photodetector full spectral photoresponse imaging

Effects of Number of Bleed Holes on Shock-Wave/Boundary-Layer Interactions in a Transonic Compressor Stator

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第2期33卷 611-624页

作者： LI Bai ZHOU Xun LUO Lei DU Wei School of Energy Science and engineering Harbin Institute of TechnologyHarbin150001China

An extensive numerical investigation is conducted to characterize the flow separation control in a transonic compressor cascade with a porous *** bleed holes are arranged on the suction surface in a single row,two staggered rows and three staggered *** each bleed scheme,five bleed pressure ratios are examined at an inlet Mach number of *** results indicate that the aerodynamic performance of the cascade is significantly improved by the porous *** the single-row scheme,the maximum reduction in total pressure losses is 57%.For the two-staggered-row and three-staggered-row schemes,there is an optimal bleed pressure ratio of 1.0,and the maximum reductions in total pressure loss are 68% and 75%,*** low loss in the cascade is due to the well-controlled boundary *** new local supersonic region created by the bleed hole is the key reason for the improved boundary *** vortex induced by side bleeding provides another mechanism for delaying flow *** the bleed holes could create multiple local supersonic regions,which reduce the range of the adverse pressure gradient that the boundary layer needs to *** is the reason why cascades with more bleed holes perform better.

关键词： transonic compressor stator shock wave/boundary layer interaction porous bleed number of bleed holes

Corrosion evaluation and resistance study of alloys in chloride salts for concentrating solar power plants

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第3期43卷 1222-1233页

作者： Dong-Mei Han Yong Shuai Bachirou Guene Lougou Bo-Xi Geng Xi-Bo He Tian-Tian Yan Jia-Meng Song School of Energy Science and engineering Harbin Institute of TechnologyHarbin150001China

Thermal energy storage(TES)systems based on molten salt are widely used in concentrating solar power(CSP)*** investigation of the corrosion behavior of alloy materials in molten salt is crucial for the correct selection of alloy materials and the design of TES *** this study,the corrosion behavior of 304,31.S,31.,and In625 alloys in molten chloride salts(27 mol%NaCl-22 mol%KCl-51.mol%MgCl,)was *** evolution of mass loss of the alloy samples with corrosion time and temperature and the analysis of the experimental results by scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)revealed the corrosion mechanism of the alloy samples in molten chloride *** main factors affecting the corrosion of the alloy samples were further *** was found that the loose multi-layer corrosion was formed on the surface of the corroded alloy samples with the increase in corrosion ***,the experimental *** that Mo played a positive role in improving the corrosion resistance of the alloy samples because the presence of Mo could inhibit the outward diffusion of alloying element *** work enriches the molten salt corrosion database and provides a reference for the selection of alloy materials for TES systems with potential application in CSP plants.

关键词： Thermal energy storage Molten chloride salt Alloy materials Corrosion mechanism Corrosion resistance

Heat Transfer and Flow Structure of a Turbine Blade's Air-cooled Leading Edge Considering Different Hole Shapes and Additional Flow Angles

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第4期33卷 1421-1442页

作者： QIN Runxuan ZHOU Xun WANG Songtao CAI Le School of Energy Science and engineering Harbin Institute of TechnologyHarbin150001China

A numerical study is conducted to elucidate the impact of hole shapes and additional flow angles on the flow structure of the coolant and temperature field in the leading edge area of the gas turbine *** typical hole shapes are considered for the GE-E3 *** impact of the additional flow angle(E)within each hole shape on the temperature field is *** results indicate that for the leading edge area and suction surface,the fan-shaped hole case performs best in decreasing temperatures,with a decrease of about 43 *** is mainly due to the fact that the fan-shaped hole has the maximum expansion in hole spanwise *** the pressure surface,the console hole case performs best in decreasing temperatures,with a maximum reduction of about 47.2 *** influence of E on the surface temperature at leading edge area varied between the different hole *** the cylinder hole and console hole,the E=-20°case has the lowest area-averaged *** both the fan-shaped hole and the 7-7-7 shaped hole are expansion holes,the pattern of variation of the leading edge area temperature with increasing E is similar for the fan-shaped hole case and 7-7-7 shaped hole *** E=20°case shows the lowest spanwise-averaged temperature near the hole outlet,and the E=-20°case shows the lowest spanwise-averaged temperature further downstream.

关键词： film cooling GE-E3 turbine rotor blade conjugate heat transfer leading edge