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Calculation Energy of Efficiency New Ginning Machine 被引量:2
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作者 Shuhrat Mamatovich Azizov 《Engineering(科研)》 2022年第4期163-172,共10页
Having studied the schedule of influence and change of static loading depending on angular an arrangement saw cylinders we have defined the general spent electric energy on the single-chamber two-cylinder gin, by perf... Having studied the schedule of influence and change of static loading depending on angular an arrangement saw cylinders we have defined the general spent electric energy on the single-chamber two-cylinder gin, by performing of the calculation the energy consumption per one saw with respect to the angular arrangement of the saw cylinder. Also, provide energy audits gin, were performed at Uzbekistan Namangan region cotton gins in ten manufactures. 展开更多
关键词 Saw Cylinder Performed calculation CORNER Loading Distributions Wear Resistance Energy efficiency
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Transformation optics for efficient calculation of transmembrane voltage induced on cells
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作者 廖胤鸿 朱铧丞 +1 位作者 唐正明 黄卡玛 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期31-35,共5页
We present a novel efficient approach in calculating induced transmembrane voltage(ITV) on cells based on transformation optics. As cell membrane is much thinner than the dimension of a typical cell, discretizing th... We present a novel efficient approach in calculating induced transmembrane voltage(ITV) on cells based on transformation optics. As cell membrane is much thinner than the dimension of a typical cell, discretizing the membrane needs numerous meshes. Using an anisotropic medium based on transformation optics, the thickness of the membrane can be exaggerated by at least one order, which eliminates rigorous mesh refinement and reduces unknowns greatly. The accuracy and efficiency of the proposed method are verified by a cylindrical cell model. Moreover, the influence on ITV with bound water(BW) layers is also studied. The results show that when cells are exposed to nanosecond electric field, BW layers should be rigorously considered in calculating ITV. 展开更多
关键词 efficient calculation transmembrane voltage transformation optics anisotropic medium mem- brane bound water layer
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Study on the influence of armature on the efficiency of reluctance accelerator 被引量:3
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作者 Hui-min Deng Yu Wang Zhong-ming Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第2期293-304,共12页
The armature is an important part affecting the energy conversion efficiency of a reluctance accelerator.In this paper,six kinds of soft magnetic materials are chosen and four structures are designed for the armature.... The armature is an important part affecting the energy conversion efficiency of a reluctance accelerator.In this paper,six kinds of soft magnetic materials are chosen and four structures are designed for the armature.At first,the circuit and magnetic force are theoretically analyzed.Then the armatures with different materials and structures are used in the simulation,and the performances are compared and analyzed.At last,the experiment verifies the theory analysis and simulation design.It is concluded that the saturation flux density and conductivity of the material are the key factors affecting the armature force,and the optimization of armature structure can effectively restrain the eddy current,reduce negative force and improve efficiency.Compared with cutting slits in solid armatures,laminating the sheets radially can reduce the eddy current more efficiently.Although slitting can prevent the eddy current to a certain extent,meanwhile,it will decrease the magnetic force because of the losing of magnetized volume and the surface area.Hence,choosing the high saturation flux density material and making out the armature with radially_laminated sheets will improve the efficiency of the reluctance accelerator.In this paper,the silicon steel radially_laminated armature is a better choice for the armature design of the reluctance accelerator. 展开更多
关键词 Reluctance accelerator Armature design Soft magnetic material Magnetic force calculation Energy transformation efficiency
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Experimental and theoretical insight into carbamazepine degradation by chlorine-based advanced oxidation processes:Efficiency,energy consumption,mechanism and DBPs formation 被引量:1
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作者 Chunwei Liu Zuo Tong How +3 位作者 Yue Ju Li Feng Xuefeng Ren Mohamed Gamal El-Din 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第5期72-83,共12页
Chlorine has been widely used in different advanced oxidation processes(AOPs)for micropollutants removal.In this study,different chlorine-based AOPs,namely medium pressure(MP)UV/chlorine,low pressure(LP)UV/chlorine,an... Chlorine has been widely used in different advanced oxidation processes(AOPs)for micropollutants removal.In this study,different chlorine-based AOPs,namely medium pressure(MP)UV/chlorine,low pressure(LP)UV/chlorine,and in-situ chlorination,were compared for carbamazepine(CBZ)removal efficiency,energy consumption,and disinfection by-products(DBPs)formation.All three processes could achieve nearly 100%CBZ removal,while the reaction time needed by in-situ chlorination was double the time required by UV/chlorine processes.The energy consumed per magnitude of CBZ removed(EE/O)of MP UV/chlorine was 13 times higher than that of LP UV/chlorine,and relative to that of in-situ chlorination process.Accordingly,MP and LP UV/chlorine processes generated one to two orders of magnitude more hydroxyl radicals(^(·)OH)and reactive chlorine species(RCS)than in-situ chlorination.Besides,RCS were the dominant reactive species,contributing to 78.3%,75.6%,and 71.6% of CBZ removal in MP,LP UV/chlorine,and in-situ chlorination,respectively.According to the Gibbs free energy barriers between CBZ and RCS/^(·)OH calculated based on density functional theory(DFT),RCS had more reaction routes with CBZ and showed lower energy barrier in the main CBZ degradation pathways like epoxidation and formation of iminostilbene.When applied to secondary wastewater effluent,UV/chlorine and in-situ chlorination produced overall DBPs ranging from 104.77 to 135.41μg/L.However,the production of chlorate during UV/chlorine processes was 15 times higher than that during in-situ chlorination. 展开更多
关键词 UV/chlorine In-situ chlorination Energy efficiency Role of reactive species DFT calculation Disinfection by-products
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Precision Improvement of the Discrete Calculation Method for Sound Radiation Research
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作者 罗智 郝志勇 郑旭 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第4期415-419,共5页
Sound radiation of thin plates is a common problem in engineering. Hashimoto proposed the discrete calculation method(DCM) to deal with the problem. The calculation of the radiation impedance of the rectangular elemen... Sound radiation of thin plates is a common problem in engineering. Hashimoto proposed the discrete calculation method(DCM) to deal with the problem. The calculation of the radiation impedance of the rectangular element is more cumbersome than that of the circular one, so the discrete rectangular radiation element is approximated by the circular one. However, error is also introduced. The formula developed by Sha has been employed to get self- and mutual-radiation impedances of rectangular radiation element. Numerical study was performed to verify error introduced by the approximation Hashimoto adopted. Experimental researches on sound radiation of a 2 mm-thick and a 4 mm-thick magnesium alloy plates were also carried out to evaluate the errors introduced by the approximation. The experimental results indicate that the circular approximation Hashimoto adopted overestimates the sound radiation efficiency. The maximum error levels of the radiation efficiencies of the2 mm-thick and 4 mm-thick magnesium alloy plates are up to 0.15 and 0.12, respectively. The effect of element aspect ratio on the sound radiation efficiency is also remarkable. 展开更多
关键词 discrete calculation method radiation impedance sound radiation efficiency sound radiation power
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The mechanical measuring method of welding heat source efficiency 被引量:1
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作者 张建强 张国栋 +2 位作者 何洁 王承权 陈冰泉 《China Welding》 EI CAS 2007年第4期51-55,共5页
Based on the principle of residual deformation induced by superposition of the welding residual stress and working stress, the welding heat source efficiency has been determined by measuring displacement changes of sp... Based on the principle of residual deformation induced by superposition of the welding residual stress and working stress, the welding heat source efficiency has been determined by measuring displacement changes of specimens under loading and unloading in tensile tests, and combining with calculating welding parameters. Meanwhile, the welding heat source eficiencies obtained are compared with those of the measuring-calculating method. The research results show that the welding heat source efficiencies are almost the same as those obtained by the measuring-calculating method. Therefore, the welding heat source efficiency can be determined accurately by this method, and a new determining method of the heat source efficiency for the welding heat process calculating has been provided. 展开更多
关键词 welding heat source efficiency welding stress welding distortion mechanical measuring-calculating method
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Production calculation of the second and tertiary recovery combination reservoirs under chemical flooding
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作者 LIU Weidong WANG Gaofeng +4 位作者 LIAO Guangzhi WANG Hongzhuang WANG Zhengmao WANG Qiang WANG Zhengbo 《Petroleum Exploration and Development》 CSCD 2021年第6期1403-1410,共8页
Based on the analysis of the production composition of reservoirs developed by the second&tertiary recovery combination(STRC),the relationship between the overall output of the STRC project and the production leve... Based on the analysis of the production composition of reservoirs developed by the second&tertiary recovery combination(STRC),the relationship between the overall output of the STRC project and the production level during the blank water flooding stage is proposed.According to the basic principle of reservoir engineering that the“recovery factor is equal to sweeping coefficient multiplied by oil displacement efficiency”,the formula for calculating the ultimate oil recovery factor of chemical combination flooding reservoir was established.By dividing the reservoir into a series of grids according to differen-tial calculus thinking,the relationship between the ultimate recovery factor of a certain number of grids and the recovery de-gree of the reservoir was established,and then the variation law of oil production rate of the STRC reservoir was obtained.The concept of“oil rate enlargement factor of chemical combination flooding”was defined,and a production calculation method of reservoir developed by STRC was put forward based on practical oilfield development experience.The study shows that the oil production enhancing effect of STRC increases evenly with the in crease of the ratio of STRC displacement efficiency to water displacement efficiency,and increases rapidly with the increase of the ratio of recovery degree at flooding mode conversion to the water displacement efficiency.STRC is more effective in increasing oil production of reservoir with high recovery degree.Through practical tests of the alkali free binary flooding(polymer/surfactant)projects,the relative error of the oil production calculation method of STRC reservoir is about±10%,which meets the requirements of reservoir engineering. 展开更多
关键词 chemical combination flooding second&tertiary recovery combination oil displacement efficiency oil rate en-largement factor of chemical flooding oil production calculation
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Overview of Efficient Numerical Computing Methods Based on Deep Learning
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作者 Kejun Yang 《Journal of Electronic Research and Application》 2025年第2期117-124,共8页
This article reviews the application and progress of deep learning in efficient numerical computing methods.Deep learning,as an important branch of machine learning,provides new ideas for numerical computation by cons... This article reviews the application and progress of deep learning in efficient numerical computing methods.Deep learning,as an important branch of machine learning,provides new ideas for numerical computation by constructing multi-layer neural networks to simulate the learning process of the human brain.The article explores the application of deep learning in solving partial differential equations,optimizing problems,and data-driven modeling,and analyzes its advantages in computational efficiency,accuracy,and adaptability.At the same time,this article also points out the challenges faced by deep learning numerical computation methods in terms of computational efficiency,interpretability,and generalization ability,and proposes strategies and future development directions for integrating with traditional numerical methods. 展开更多
关键词 Deep learning efficient numerical value Method of calculation
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诱导轮离心泵速度系数水力设计方法及其实验研究
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作者 沙毅 曹玉华 +3 位作者 李林 李彦霞 周金伟 陈秋帆 《机电工程》 北大核心 2026年第1期159-167,共9页
针对如何简明扼要设计出诱导轮离心泵,并揭示其与同比转数普通离心泵在结构和性能上的主要差别的问题,在离心泵速度系数水力设计基础上,进一步拟合出了诱导轮离心泵容积效率和叶轮进口速度系数改型计算公式,总结出了诱导轮离心泵的简明... 针对如何简明扼要设计出诱导轮离心泵,并揭示其与同比转数普通离心泵在结构和性能上的主要差别的问题,在离心泵速度系数水力设计基础上,进一步拟合出了诱导轮离心泵容积效率和叶轮进口速度系数改型计算公式,总结出了诱导轮离心泵的简明设计方法。首先,阐述了普通离心泵叶轮的水力几何计算过程和诱导轮离心泵速度系数水力设计过程,成功地开发出了比转数n s=70型CB250-140-330普通离心泵和YCB120-85-260诱导轮离心泵产品,以此验证该设计方法的实用性、简要性、优化性和准确性;然后,通过普通离心泵和诱导轮离心泵性能试验,对泵性能试验曲线进行了对比分析,阐述了诱导轮离心泵在泵效率、汽蚀余量(NPSH)等方面的技术指标和主要特性;最后,运用汽蚀基本方程式进行了分析,阐明了诱导轮离心泵抗汽蚀原理。研究结果表明:加装诱导轮可以使离心泵的汽蚀余量(NPSH)下降到1 m及以下,但比同类型普通离心泵效率降低了2.6%。该研究阐述了一个完整、全面的诱导轮离心泵研发案例,可为今后诱导轮离心泵的优化设计提供科学依据。 展开更多
关键词 诱导轮离心泵 结构和性能分析 容积效率 叶轮进口直径计算公式 技术指标参数 汽蚀余量
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风−列车−桥梁耦合振动研究进展
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作者 韩艳 胡朋 +2 位作者 王力东 刘汉云 蔡春声 《力学进展》 北大核心 2025年第2期378-418,共41页
开展风−列车−桥梁(简称风−车−桥)耦合振动研究是保障强风下桥上列车安全运行的重要手段之一.近二十年来,国内外学者在该领域进行了大量研究,积累了丰硕的研究成果.风−车−桥耦合振动研究主要包括三个方面,即车−桥系统气动特性、风−车−桥... 开展风−列车−桥梁(简称风−车−桥)耦合振动研究是保障强风下桥上列车安全运行的重要手段之一.近二十年来,国内外学者在该领域进行了大量研究,积累了丰硕的研究成果.风−车−桥耦合振动研究主要包括三个方面,即车−桥系统气动特性、风−车−桥系统动力响应计算和行车安全评估与防控.首先,车−桥系统气动特性研究的主要目的是分析车−桥系统气动干扰机理以及准确获取作用在车辆和桥梁上的风载荷.根据桥上车辆是否移动,可分为静止车辆和移动车辆两种情形.其次,在获得车−桥系统风载荷的基础上,需求解风−车−桥系统以获得车辆通过桥梁全过程的动力响应时程曲线.该方面研究主要包括车−桥系统建模方法、风−车−桥系统动力计算理论以及高效计算方法.再次,基于已获得的动力响应,最终目的是评估强风下桥上车辆的行车安全性以及提出防控措施.该方面主要包括行车安全评估指标和方法,以及强风下保障列车行车安全的主要防控手段.最后,结合风−车−桥耦合振动领域目前存在的主要问题与新技术发展,对未来重点研究方向进行了展望,以促进本研究领域的发展. 展开更多
关键词 风−车−桥系统 气动特性 高效计算 评估和防控
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串联谐振型DAB变换器回流功率及损耗优化策略
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作者 李宁 杨家林 +2 位作者 田博文 李洁 张岩 《电源学报》 北大核心 2025年第5期1-9,共9页
以串联谐振型DAB变换器SRDAB(series resonant DAB)为研究对象,针对在移相调制策略下SRDAB变换器运行效率的问题,提出1种回流功率减小的效率优化策略。首先,在移相调制下建立SRDAB变换器传输效率的数学模型,推导出变换器工作时回流功率... 以串联谐振型DAB变换器SRDAB(series resonant DAB)为研究对象,针对在移相调制策略下SRDAB变换器运行效率的问题,提出1种回流功率减小的效率优化策略。首先,在移相调制下建立SRDAB变换器传输效率的数学模型,推导出变换器工作时回流功率的数学表达式,得出影响变换器回流功率的参数。其次,计算变换器运行时产生的暂态损耗与通态损耗数学表达式,构建变换器运行效率数学模型,得出移相比和开关频率与谐振频率之比二者与变换器效率的关系,进而优化这2个关键参数使运行效率提升。最后,通过搭建仿真和实验电路验证了效率优化策略的正确性和有效性。 展开更多
关键词 串联谐振型DAB变换器 损耗计算 效率优化 功率回流
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含齿轮变速与链式传动机构的斜坡重力储能系统能效分析模型与实验验证 被引量:3
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作者 高天 王祖凡 +4 位作者 方舒扬 张佑康 张连成 黄永章 赵海森 《储能科学与技术》 北大核心 2025年第2期688-698,共11页
为了研究传送链式斜坡重力储能系统(transmission chain slope gravity energy storage system,TCS-GESS)充放电过程的能量转换效率及各环节损耗占比,针对系统质量块移动、机械传动以及电气驱动环节,推导了各环节损耗数学表达式及相应... 为了研究传送链式斜坡重力储能系统(transmission chain slope gravity energy storage system,TCS-GESS)充放电过程的能量转换效率及各环节损耗占比,针对系统质量块移动、机械传动以及电气驱动环节,推导了各环节损耗数学表达式及相应的能效计算方法,在此基础上,建立了基于MATLAB/Simulink的TCS-GESS能效分析模型。以一套2.2 kW重力储能样机为例,设计了充放电工况下的实验方案并实测了不同负载条件下系统各环节能效,从速度、机械功率、充放电功率、传动损耗以及电机损耗五个维度与能效计算结果进行对比,验证了能效分析模型的准确性与实用性。结果显示,随负载增加系统效率逐渐提高,其中链条损耗占比较大,齿轮箱和齿轮盘损耗变化不大且占比较小,电机损耗占比中等且充/放电工况下随着加载均有所增加。额定负载工况下充放电效率分别为59.5%和37.4%,系统效率为23.2%;进一步对具有相同传动机构、不同功率等级下重力储能系统充放电效率进行预测,结果表明系统容量低于1 MW时充放电效率将低于68%,容量高于10 MW时系统能效提升潜力有限,即采用文中传动机构的重力储能单机系统最佳功率范围宜选取在1~10 MW。 展开更多
关键词 重力储能系统(GESS) 链式传动 损耗计算 能效模型
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基于带传动的垂直式重力储能系统能效分析模型与实验验证 被引量:2
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作者 王青山 李妍 +4 位作者 张群 汪德成 吴高昀 王祖凡 赵海森 《储能科学与技术》 北大核心 2025年第3期1141-1149,共9页
重力储能系统(GESS)因其长时、大容量、零自放电率、安全性高等优点受到广泛关注,而能效水平是影响GESS规模化推广应用的重要因素。首先,针对基于带传动的垂直式GESS,分析机械环节中动/定滑轮相对于轴承表面的滑动摩擦、曳引系统的球轴... 重力储能系统(GESS)因其长时、大容量、零自放电率、安全性高等优点受到广泛关注,而能效水平是影响GESS规模化推广应用的重要因素。首先,针对基于带传动的垂直式GESS,分析机械环节中动/定滑轮相对于轴承表面的滑动摩擦、曳引系统的球轴承摩擦、传动带相对于带轮的弹性滑动摩擦及电气环节中电机的铜耗、铁耗、风摩耗、杂散损耗,推导了系统各环节效率及损耗的理论计算方法。其次,针对所提理论计算方法设计了算例,算例结果表明,机械环节效率随质量块质量增加而略有减小;系统充电效率随质量块质量增加而先增加后减小;系统放电效率随质量块质量增加而增加;放电工况下,系统机械损耗占比与充电工况相比明显增加。最后,通过搭建1.1 kW样机对算例结果进行实验验证,实验结果表明,当质量块为127.35 kg时,充、放电状态下电机损耗实测占比分别为82.77%和72.42%,与算例得到的电机损耗理论占比80.56%和72.96%较为接近,且系统充、放电效率随质量块质量的理论变化曲线与实测曲线趋势相同,验证了所提能效分析方法的正确性和实用性。 展开更多
关键词 垂直式重力储能 带传动 能效分析 损耗计算
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典型密闭小空间的氮气灭火效能分析与仿真 被引量:1
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作者 陈国锋 李盼 +3 位作者 俞健 黄琨 赵宗凯 张宇伦 《船海工程》 北大核心 2025年第2期1-5,共5页
针对舰船密闭空间火灾及氮气灭火效能问题,以舰船小型密闭空间为研究对象,研究氮气灭火系统效能。通过理论分析,确定火灾燃烧及氮气释放时空间内氧气浓度变化规律,考虑火源设置及不同燃烧条件下氧气含量变化。构建物理和数值模型,模拟... 针对舰船密闭空间火灾及氮气灭火效能问题,以舰船小型密闭空间为研究对象,研究氮气灭火系统效能。通过理论分析,确定火灾燃烧及氮气释放时空间内氧气浓度变化规律,考虑火源设置及不同燃烧条件下氧气含量变化。构建物理和数值模型,模拟小型房间火灾场景,设置不同灭火剂喷放时间,通过FDS对典型小空间的火灾场景进行数值仿真计算。结果表明,空间内的氧气浓度变化规律、燃烧终止时间的数值模拟结果与理论预测值一致,喷射时间越短灭火越早。 展开更多
关键词 氮气灭火系统 效能分析 理论计算 数值仿真
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方程组降阶算法及其在电工装备数值计算中的应用
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作者 金军 阎秀恪 +2 位作者 钟立国 张艳丽 任自艳 《电工技术学报》 北大核心 2025年第7期2020-2032,共13页
大型电气设备在进行有限元分析时,会遇到大规模数值计算问题。代数方程组阶数巨大导致计算时间长,计算效率低,有时甚至无法求解。该文研究有限元代数方程组的降阶求解,推导了分块迭代算法、正交降阶分解算法(OORDA),将禁忌搜索算法引入... 大型电气设备在进行有限元分析时,会遇到大规模数值计算问题。代数方程组阶数巨大导致计算时间长,计算效率低,有时甚至无法求解。该文研究有限元代数方程组的降阶求解,推导了分块迭代算法、正交降阶分解算法(OORDA),将禁忌搜索算法引入高斯消元法形成改进的高斯消元法(IGEM),提出了分块迭代算法分别与OORDA和IGEM相结合的方程组混合降阶算法,并通过编程实现。将OORDA、IGEM和两种混合降阶算法分别应用于长直载流导体的磁场有限元计算中,计算结果与解析解的对比验证了算法的正确性。将四种算法应用到单相变压器的磁场有限元计算中,两种混合降阶算法能够快速大幅降低方程组阶数,提高计算效率。该文提出的降阶算法可应用于电工装备物理场的大规模数值计算中,能显著提高复杂模型的有限元计算效率。 展开更多
关键词 有限元分析 代数方程组 降阶算法 大规模数值计算 计算效率
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基于DDAA的SNM探测系统蒙特卡罗模拟优化设计
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作者 张连军 郑玉来 +5 位作者 唐梦娇 李永 刘超 王强 王国宝 张晨 《核技术》 北大核心 2025年第2期124-132,共9页
差分衰减分析技术(Differential Die-away Analysis,DDAA)可用于特殊核材料(Special Nuclear Materials,SNM)主动探测分析,无论核材料是否置于屏蔽体内,它皆可通过外加脉冲中子诱发核材料发生裂变来揭示核材料的存在。通过Geant4蒙特卡... 差分衰减分析技术(Differential Die-away Analysis,DDAA)可用于特殊核材料(Special Nuclear Materials,SNM)主动探测分析,无论核材料是否置于屏蔽体内,它皆可通过外加脉冲中子诱发核材料发生裂变来揭示核材料的存在。通过Geant4蒙特卡罗模拟软件设计基于DDAA技术的SNM探测系统,优化探测系统关键参数以及系统不同几何布置,获得探测系统达到最优灵敏度时的几何结构参数。计算结果表明,当探测系统的几何参数选择压强为0.405 3 MPa、直径5.08 cm的3He管,3He管外包裹密度为1.10 g·cm^(-3)、厚度为4 cm的慢化体,样品周围采用厚度为7 cm、密度为0.85 g·cm^(-3)的慢化体时,可达到1 g的235U核材料高灵敏探测。计算结果对基于DDAA技术的SNM探测系统的参数设计具有重要意义。 展开更多
关键词 差分衰减分析 特殊核材料 探测效率 优化计算
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一种高效的梁耦合结构动力学特性分析方法
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作者 李直兵 靳国永 +2 位作者 仲赛凤 叶天贵 杨铁军 《哈尔滨工程大学学报》 北大核心 2025年第6期1169-1178,共10页
为了快速预报梁耦合结构的动力学特性,本文将梁的精确解析公式与有限元分析软件的前处理功能相结合,提出了一种高效动力学分析方法。基于梁结构控制微分方程,推导了梁单元的精确动力学刚度矩阵;利用ANSYS Mechanical APDL平台建立了梁... 为了快速预报梁耦合结构的动力学特性,本文将梁的精确解析公式与有限元分析软件的前处理功能相结合,提出了一种高效动力学分析方法。基于梁结构控制微分方程,推导了梁单元的精确动力学刚度矩阵;利用ANSYS Mechanical APDL平台建立了梁耦合结构的几何模型,并对其进行单元离散,获取结构的单元和节点信息。与有限元方法的离散策略不同,由于本文方法采用了精确的动力学刚度单元,每根梁仅需离散为一个单元;将单元和节点信息导出,并在数值计算软件中与梁单元的动力学刚度矩阵进行组装,构建了耦合结构的整体动力学方程。在此基础上,求解了多种梁耦合结构的强迫振动响应,并将计算结果与ANSYS的仿真值进行了对比。结果表明:相比于传统有限元方法,本文方法显著减少了计算所需单元和节点数量,提高了计算效率。 展开更多
关键词 梁耦合结构 动刚度矩阵 精确解析解 强迫振动 动力学分析 计算效率 计算精度 有限元分析
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基于全局补偿的IMU阵列姿态融合方法
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作者 杨在柱 管练武 +2 位作者 李玺 杨明 从晓丹 《传感器与微系统》 北大核心 2025年第S1期108-113,共6页
为了解决传统惯性测量单元(IMU)阵列IMU层级融合算法易受安装误差影响、姿态解算层级融合算法计算复杂度高的问题,提出了一种基于全局补偿值共享的IMU阵列姿态解算方法。首先对IMU数据进行预处理与加权融合,然后计算全局误差补偿值并反... 为了解决传统惯性测量单元(IMU)阵列IMU层级融合算法易受安装误差影响、姿态解算层级融合算法计算复杂度高的问题,提出了一种基于全局补偿值共享的IMU阵列姿态解算方法。首先对IMU数据进行预处理与加权融合,然后计算全局误差补偿值并反馈至各IMU,最后加权融合每个IMU解算出的姿态数据得到最终输出。实验结果表明,在三种不同的运动状态下,本文算法解算出的俯仰角与横滚角的均方根误差相较于单个IMU降低了1~2倍,计算时间仅为0.077 ms,显著优于姿态解算层级融合算法。该方法为动态场景中IMU阵列的姿态估计提供了一种高效、鲁棒的解决方案。 展开更多
关键词 惯性测量单元阵列 姿态解算 自适应Mahony 全局补偿值共享 高效计算
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An energy-based method for uniaxially compressed rocks and its implication 被引量:1
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作者 Yong Luo Jiancheng Huang +2 位作者 Xuefeng Si Feng Lin Wuxing Wu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1429-1444,共16页
To obtain the precise calculation method for the peak energy density and energy evolution properties of rocks subjected to uniaxial compression(UC)before the post-peak stage,particularly at s0.9sc(s denotes stress and... To obtain the precise calculation method for the peak energy density and energy evolution properties of rocks subjected to uniaxial compression(UC)before the post-peak stage,particularly at s0.9sc(s denotes stress and sc is the peak strength),extensive UC and uniaxial graded cyclical loading-unloading(GCLU)tests were performed on four rock types.In the GCLU tests,four unloading stress levels were designated when σ<0.9σc and six unloading stress levels were designated forσ≥0.9σc.The variations in the elastic energy density(ue),dissipative energy density(ud),and energy storage efficiency(C)for the four rock types under GCLU tests were analyzed.Based on the variation of ue whenσ≥0:9σc,a method for calculating the peak energy density was proposed.The energy evolution in rock under UC condition before the post-peak stage was examined.The relationship between C0.9(C atσ≥0:9σc)and mechanical behavior of rocks was explored,and the damage evolution of rock was analyzed in view of energy.Compared with that of the three existing methods,the accuracy of the calculation method of peak energy density proposed in this study is higher.These findings could provide a theoretical foundation for more accurately revealing the failure behavior of rock from an energy perspective. 展开更多
关键词 calculation method of peak energy density Energy evolution Energy storage efficiency Damage threshold
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2K-H型行星轮系的角动能效率计算方法研究
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作者 冯英智 孙伟 +3 位作者 汤勃 王桦寅 李豪华 李延康 《机电工程》 北大核心 2025年第5期913-920,共8页
相比较于蜗轮蜗杆自锁机构,自锁行星轮系具有结构紧凑、扭矩传递大和多变速比等优点,但轮系效率计算方法存在精度不准确和计算困难的问题。为此,基于现有的行星轮系自锁效率计算方法,提出了一种轮系构件角动能计算自锁效率的方法。首先... 相比较于蜗轮蜗杆自锁机构,自锁行星轮系具有结构紧凑、扭矩传递大和多变速比等优点,但轮系效率计算方法存在精度不准确和计算困难的问题。为此,基于现有的行星轮系自锁效率计算方法,提出了一种轮系构件角动能计算自锁效率的方法。首先,分析了该轮系的自锁条件,确认了其自锁区间,采用啮合功率法和传动比法对轮系效率进行了计算,得出了该轮系的正反向效率值;然后,基于啮合功率法,建立了轮系的角动能数学模型,采用仿真软件获得了目标构件的角动能,得出了角动能法的计算结果,并将其计算结果与已有各种方法的计算结果进行了对比分析;最后,为了验证轮系构件角动能计算自锁方法的准确性与便捷性,对行星轮系进行了效率最大化分析。研究结果表明:与采用啮合功率法、传动比法的计算结果相比,采用角动能法的计算结果误差分别为-0.73%和+1.77%,最大效率为46.04%。上述结果验证了角动能法的简便性和计算准确性,也验证了其在实际应用中的有效性。 展开更多
关键词 2K-H型轮系 自锁效率计算方法 啮合功率法 传动比法 轮系正反向效率值 轮系效率计算
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