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海绵交通系统供需协同调蓄 被引量:1
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作者 汪怡然 陈景旭 +2 位作者 丁闪闪 王岳平 刘志远 《交通科技与经济》 2022年第5期1-7,共7页
针对国内城镇化水平持续增长、城市交通系统供需矛盾长期存在的问题,以“分、督、蓄、渗、排”5大要素为支撑,构建“5S型”城市交通系统“海绵”功能,通过城市交通规划布局理念的革新和交通系统内部的协同调蓄,解决供需矛盾。海绵交通... 针对国内城镇化水平持续增长、城市交通系统供需矛盾长期存在的问题,以“分、督、蓄、渗、排”5大要素为支撑,构建“5S型”城市交通系统“海绵”功能,通过城市交通规划布局理念的革新和交通系统内部的协同调蓄,解决供需矛盾。海绵交通系统的内涵以发展组团型智慧城市为基础,将监测管理手段、基础设施建设和出行结构调整相结合,以绿色出行观念和公交优先发展为落脚点,由停车换乘和多模式公交组成“海绵”功能的核心,强化交通系统的运力弹性,从容应对城市客流变化。海绵交通系统转变以机动化出行为导向的交通规划理念,以人的出行体验为价值尺度,探索城市交通供需管理新思路。 展开更多
关键词 城市交通 系统设计 协同调蓄 海绵交通 运力弹性
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A parametric study on the contact stress of half toroidal continuously variable transmission 被引量:3
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作者 NabilAbdullaAttia QINDatong +1 位作者 SHIWankai LIHuaying 《Journal of Chongqing University》 CAS 2003年第2期6-11,共6页
The most general contact in mechanical transmission is the elliptical one. In particular, a toroidal continuously variable transmission (CVT) has an elliptical shape in the contact area under the elastohydrodynamic lu... The most general contact in mechanical transmission is the elliptical one. In particular, a toroidal continuously variable transmission (CVT) has an elliptical shape in the contact area under the elastohydrodynamic lubrication regime, where the shearing of the fluid subjects to high contact stress and transmits the power. Many parameters affect the contact service performance of the half toroidal CVT, which include the properties of the contacting material (Young抯 modulus), operating parameters (input torque and maximum traction coefficient) and geometrical parameters (aspect cavity ratio, curvature ratio and half cone angle of the power roller). In this paper, the contacts between the input disk, the power roller and the output disk are formulated using the classical Hertzian contact theory. Based on the formulated equations, different system parameters, which affect the maximum Hertzian stresses, are compared. The comparative results will provide some observations of the relations between the maximum Hertzian stresses and transmission ratios in the form of graphs. These graphs give useful information for designer to know the maximum Hertzian stress during operation in such systems. 展开更多
关键词 CVT Half toroidal elliptical contact Hertzian stress operating PARAMETERS
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Controller design based on viscoelasticity dynamics model and experiment for flexible drive unit 被引量:1
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作者 吴伟国 侯月阳 《Journal of Central South University》 SCIE EI CAS 2014年第12期4468-4477,共10页
In order to ensure that the system has the advantage of light weight and vibration absorption, the steel rope is used as a flexible transmission part. A flexible drive unit(FDU) is developed, whose features are guided... In order to ensure that the system has the advantage of light weight and vibration absorption, the steel rope is used as a flexible transmission part. A flexible drive unit(FDU) is developed, whose features are guided by steel rope, increasing force by the movable pulley group, modular, convenient and flexible. Dynamics model for controller is deduced based on the constitutive equation of viscoelasticity. Controller is designed for position control and is based on the viscoelasticity dynamics model compensation control strategy proposed. The control system is based on the TURBO PMAC multi-axis motion control card.Prototype loading experiments and velocity experiments results show that the FDU can reach 2 Hz with no load and the max speed of 30(°)/s. The FDU has the capability of the load torque 11.2 N·m and the speed of 24(°)/s simultaneously, and the frequency response is 1.3 Hz. The FDU can be used to be the pitch joint of hip for biped robot whose walking speed is 0.144 km/h theoretically. 展开更多
关键词 flexible drive unit steel rope drive viscoelasticity dynamic model speed-load characteristic
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A CFD/CSD model for aeroelastic calculations of large-scale wind turbines 被引量:11
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作者 GUO TongQing LU ZhiLiang +2 位作者 TANG Di WANG TongGuang DONG Lu 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第1期205-211,共7页
In this paper,a CFD/CSD model coupling N-S equations and structural equations of motion in the time domain is described for aeroelastic analysis of large wind turbines.The structural modes of blades are analyzed with ... In this paper,a CFD/CSD model coupling N-S equations and structural equations of motion in the time domain is described for aeroelastic analysis of large wind turbines.The structural modes of blades are analyzed with one-dimensional beam models.By combining point matched sliding grid for wind turbine rotation and deforming grid for structural vibrations,a hybrid dynamic grid strategy is designed for the multi-block structured grid system of a wind turbine.The dual time-stepping approach and finite volume scheme are applied to the three-dimensional unsteady preconditioned N-S equations,and DES approach is employed to simulate the unsteady massively separated flows.A modal approach is adopted to calculate the structural response,and a predictor-corrector scheme is used to solve the structural equations of motion.CFD and CSD solvers are tightly coupled via successive iterations within each physical time step.As a result,a time-domain CFD/CSD model for aeroelastic analysis of a large wind turbine is achieved.The presented method is applied to the NH1500 large wind turbine under the rated condition,and the calculated aeroelastic characteristics agree well with those of the prescribed vortex wake method. 展开更多
关键词 Large wind turbine aeroelastics time-domain method multi-block grid N-S equations structural equations of motion
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