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991.
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Kiyoshi Ohishi Tadashi Hata Takashi Sano Shinobu Yasukawa 《IEEJ Transactions on Electrical and Electronic Engineering》2009,4(2):199-209
Recently, disturbance observer has been used in many system and industry applications. This paper focus on the fine motion control technology based on disturbance observer for electric commuter train. The improvement of adhesion characteristics is important in electric commuter train. We propose the anti-slip/skid re-adhesion control system based on disturbance observer and sensor-less vector control. The effectiveness of the proposed method is confirmed by the experiment based on the actual electric commuter train, which is Series 205-5000 of East Japan Railway Company. Moreover, in order to extend the anti-slip/skid re-adhesion control considering the bogie vibration phenomenon, we propose a new anti-slip re-adhesion control based on the high order disturbance observer considering the resonant frequency of bogie system. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
994.
The dynamic performances of newly developed railway vehicles should be carefully verified step by step, from computer simulation
through the laboratory-based roller rig test to the main line trial running test. The laboratory-based roller rig test is
an effective and safe way to evaluate the dynamic characteristics such as high speed, ride comfort and dynamic behaviors.
This experimental research was performed to evaluate the dynamic performances of the 200 km/h Korean tilting train, ‘Hanvit200’,
by means of a full scale roller rig test. The newly developed tilting mechanism and stabilizer were included in the tilting
bogie to satisfy both the conflicting requirements of higher stability and higher curving performance. This paper shows the
roller rig test results and the effectiveness of tilting bogie design. Included are the roller rig test results of various
kinds of conditions such as tare and fully laden load case, normal and failed case of important bogie components, linear and
non-linear critical speed.
This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008.
Nam-Po Kim received a B.S. degree in Mechanical Engineering from Ajou University in 1985. He then went on to receive his M.S. and Ph.D.
degrees from Ajou University in 1992 and 2008, respectively. Dr. Kim is currently a principal researcher at the department
of vehicle dynamics and propulsion system at Korea Rail Road Research Institute in Uiwang, Korea. His research interests are
in the area of railway vehicle dynamics, active control of running gear for railway vehicle and vehicle system engineering. 相似文献
995.
Hyo-Won Yeom Sangkyu Yoon Hong-Gye Sung 《Journal of Mechanical Science and Technology》2009,23(1):254-261
A numerical analysis was conducted to investigate and characterize the unsteadiness of the flow structure and oscillatory
vacuum pressure inside of a supersonic diffuser equipped to simulate high-altitude rocket performance on the ground. A physical
model including a rocket motor, vacuum chamber, and diffuser, which have axisymmetric configurations was employed. Emphasis
was placed on investigating the physical phenomena of very complex and oscillatory flow evolutions in the diffuser operating
very close to the starting condition, i.e. at a minimum starting condition, which is one of the major important parameters
from a diffuser design point of view.
This paper was recommended for publication in revised form by Associate Editor Jun Sang Park
Hyo-Won Yeom received a B.S. degree in the department of Aerospace & Mechanical Engineering from Korea Aerospace University in 2007. He
is currently a master candidate at the school of Aerospace & Mechanical Engi-neering at Korea Aerospace Uni-versity in Goyang-city,
Korea. His research interests are in the area of numerical analysis for High-speed propulsion system.
Sangkyu Yoon received a B.S. degree in the department of Aerospace & Mechanical Engineering from Korea Aerospace University in 2006 and
M.S. degrees in the school of Aerospace & Mecha-nical Engineering from Korea Aerospace University in 2008. He currently works
in Hanwha Corporation R&D Center.
Hong-Gye Sung received a B.S. degree in the department of Aerospace Engineering from Inha University in 1984 and Ph.D. degree in Nuclear
and Mechanical Engineering from The Pennsylvania State University in 1999. Dr. Sung has various research experiences in the
fields of high-speed propulsion and rocket propulsion in Agency for Defense Development for 22 years (1984–2006). He is currently
a professor at the School of Aerospace and Mechanical Engineering of Korea Aerospace University in Goyang, Korea. Dr. Sung’s
research interests are in the area of propulsion, combustion, and its control. 相似文献
996.
为改善高速列车气动性能,建立一套高效的多目标气动优化设计方法,对流线型头型进行多目标气动优化设计。建立高速列车流线型头型三维参数化模型,并提取5个优化设计变量;为减少优化设计时间,利用最优拉丁超立方设计方法在优化设计空间中进行均匀采样,利用计算流体力学方法获得对应于各个采样点的气动载荷,利用Kriging代理模型构建优化设计变量和气动载荷之间的近似模型;利用多体系统动力学方法计算气动载荷作用下的高速列车轮重减载率;以气动阻力和轮重减载率为优化目标,利用多目标遗传算法NSGA-II对高速列车流线型头型进行多目标优化。优化设计变量和优化目标均呈现收敛的趋势,采用Kriging近似模型优化计算的Pareto前沿与采用CFD(Computational fluid dynamics,CFD)优化计算的Pareto前沿较为接近。优化后高速列车的气动阻力最多可降低3.27%,轮重减载率最多可降低1.44%,气动阻力最优的头型与轮重减载率最优的头型的主要差异在于中部辅助控制线的变化,前者向内凹,后者则向外凸。 相似文献
997.
Spherical 24CrNiMo alloy steel powder used for selective laser melting (SLM) fabricating high-speed train brake disc was prepared by the vacuum induction melting gas atomisation (VIGA) method. Powder morphology, particle size, flowability and microstructure were measured. Part properties fabricated by SLM were investigated via some modern analysis method. The experimental results showed that powder mean particle size D50 was 75?μm, flowability was 16.69?s/50?g and apparent density was 4.71?g?cm?3. 24CrNiMo alloy steel specimen microstructures prepared by SLM consisted of proeutectoid ferrite and granular bainite. Average microhardness was 346?HV, tensile strength was 1223?MPa, extensibility was 13.1% and the product of strength and elongation was 16.1?GPa%. 24CrNiMo alloy steel powder prepared by the VIGA method had good laser printability and huge potential application value for SLM-fabricated brake disc. 相似文献
998.
为了比较分析风电行星齿轮副啮合面和非啮面瞬态接触特性的差异,根据非线性有限元接触理论,建立了某风电增速用输入级传动机构NGW型行星轮系的非线性有限元模型,对行星齿轮副的瞬态啮合过程进行了动力学实验研究,获得了行星轮系构件齿廓不同啮合位置应力的时间历程曲线。研究表明啮合轮齿廓不同位置的应力具有相似的变化规律;与外啮合的行星齿轮轮廓应力相比,内啮合行星齿轮齿廓的应力较大。在此基础上,对比分析了风电行星齿轮副的关键工况参数对啮合面和非啮合面的瞬态接触的影响,为以改善行星齿轮啮合性能和可靠性为目标的动态优化设计方案确定提供有益的指导。 相似文献
999.
采用超声冲击工艺对转向架用SMA490BW钢对接接头焊趾表面进行冲击处理,研究了超声冲击对接头超高周疲劳性能的影响。借助金相显微镜、SEM和TEM研究了冲击层金相组织、冲击前后焊趾处的形貌及表层金属晶粒细化程度。运用有限元软件计算焊接接头的应力分布,采用X射线应力仪对冲击前后焊趾表层的应力进行了测量和分析。结果表明,在5×10~6循环周次下,冲击态接头和焊态接头的疲劳强度分别为206 MPa和153 MPa,经冲击处理后疲劳强度提高了34.6%。在1×10~8循环周次下,冲击态接头的疲劳强度为195 MPa,与焊态接头的141 MPa相比提高了38.3%。在240 MPa的应力水平下,焊接接头经超声冲击处理后的疲劳寿命提高了7倍。经冲击处理的焊趾部位的应力集中系数下降了19.1%,其表面的残余拉应力得到消除,并转变为有益的残余压缩应力,焊趾表层组织得到明显细化,这3个方面均对提高焊接接头疲劳性能起到了积极贡献。 相似文献
1000.