Double-Steady-State Test Bench of Reliability Performance of Shaft Tip Earthing Device in High-Speed Railway Vehicle

In order to find out the reason for the bogie frame instability alarm in the high-speed railway vehicle, the influence of wheel tread profile of the unstable vehicle was investigated. By means of wheel-rail contact analysis and dynamics simulation, the effect of tread wear on the bogie frame lateral stability was studied. The result indicates that the concave wear of tread is gradually aggravated with the increase of operation mileage; meanwhile the wheel-rail equivalent conicity also increases. For the rail which has not been grinded for a long time, the wear of gauge corner and wide-worn zone is relatively severe; the matching equivalent conicity is 0.31-0.4 between the worn rail and the concave-worn-tread wheel set. The equivalent conicity between the grinded rail and the concave-worn tread is below 0.25; the equivalent conicities are always below 0.1 between the reprofiled wheel set and various rails. The result of the line test indicates that the lateral acceleration of bogie frame corresponding to the worn wheel-rail can reach 8.5m/s2, and the acceleration after the grinding is reduced below 4.5m/s2. By dynamics simulation, it turns out that the unreasonable wheel-rail matching relationship is the major cause of the bogie frame lateral alarm. With the tread-concave wear being aggravated, the equivalent conicity of wheel-rail matching constantly increases, which leads to the bogie frame lateral instability and then the frame instability alarm.

Download Full-text

Summary of air permeability data from single-hole injection tests in unsaturated fractured tuffs at the Apache Leap Research Site: Results of steady-state test interpretation

10.2172/219309 ◽

1996 ◽

Cited By ~ 33

Author(s):

A.G. Guzman ◽

A.M. Geddis ◽

M.J. Henrich ◽

C.F. Lohrstorfer ◽

S.P. Neuman

Keyword(s):

Steady State ◽

Air Permeability ◽

Hole Injection ◽

Test Interpretation ◽

Single Hole ◽

Research Site ◽

State Test ◽

Steady State Test ◽

Permeability Data

Download Full-text

Modelling and evaluation of the hunting behaviour of a high-speed railway vehicle on curved track

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1177/0954409718789531 ◽

2018 ◽

Vol 233 (2) ◽

pp. 220-236 ◽

Cited By ~ 3

Author(s):

Vivek Kumar ◽

Vikas Rastogi ◽

PM Pathak

Keyword(s):

High Speed ◽

Degrees Of Freedom ◽

Critical Speed ◽

Transportation Network ◽

Graph Model ◽

Railway Vehicle ◽

Physical Damage ◽

Creep Theory ◽

High Speed Railway ◽

Hunting Behaviour

Nowadays, rail transport is a very important part of the transportation network for any countries. The demand for high operational speed makes hunting a very common instability problem in railway vehicles. Hunting leads to discomfort and causes physical damage to carriage components, such as wheels, rails, etc. The causes of instability and derailment should be identified and eliminated at the designing stage of a train to ensure its safe operation. In most of the earlier studies on hunting behaviour, a simplified model with a lower degree of freedom were considered, which resulted in incorrect results in some instances. In this study, a complete bond graph model of a railway vehicle with 31 degrees of freedom is presented to determine the response of a high-speed railway vehicle. For this purpose, two wheel–rail contacts grounded on a flange contact and Kalker’s linear creep theory are implemented. The model is simulated to observe the effects of suspension elements on the vehicle’s critical hunting velocity. It is observed that the critical hunting speed is extremely sensitive to the primary longitudinal and lateral springs. Other primary and secondary springs and dampers also affect the critical speed to some extent. However, the critical hunting velocity is insensitive to vertical suspension elements for both the primary and secondary suspensions. Also, the critical speed is found to be inversely related to the conicity of the wheel.

Download Full-text

Improved backward fatigue statistical inference to the high-speed railway vehicle components

Procedia Structural Integrity ◽

10.1016/j.prostr.2020.01.027 ◽

2019 ◽

Vol 22 ◽

pp. 211-218

Author(s):

S.C. Wu ◽

C.H. Li ◽

G.Z. Kang ◽

L.Y. Xie ◽

W.H. Zhang

Keyword(s):

Statistical Inference ◽

High Speed ◽

Railway Vehicle ◽

High Speed Railway ◽

Vehicle Components

Download Full-text

Continuous-Operation Test at Engineering Scale Uranium Crystallizer System

Volume 5: Fuel Cycle and High and Low Level Waste Management and Decommissioning; Computational Fluid Dynamics (CFD), Neutronics Methods and Coupled Codes; Instrumentation and Control ◽

10.1115/icone17-75339 ◽

2009 ◽

Author(s):

Tadahiro Washiya ◽

Toshimitsu Tayama ◽

Kazuhito Nakamura ◽

Kimihiko Yano ◽

Atsuhiro Shibata ◽

...

Keyword(s):

Steady State ◽

Crystallization Process ◽

Continuous Operation ◽

Energy Agency ◽

Monitoring Method ◽

State Test ◽

Operation Test ◽

The Stability ◽

Crystal Accumulation ◽

Steady State Test

Uranium crystallization based on solubility difference is one of the remarkable technologies which can provide simple process to separate uranium in nitric acid solution since the process is mainly controlled by temperature and concentration of solute ions. Japan Atomic Energy Agency (JAEA) and Mitsubishi Materials Corporation (MMC) are developing the crystallization process for elemental technology of FBR fuel reprocessing.[1–3] The uranium (U) crystallization process is a key technology for New Extraction System for TRU Recovery (NEXT) process that was evaluated as the most promising process for future FBR reprocessing.[4–6] We had developed an innovative crystallizer and carried out several fundamental investigations. On the basis of the results, we fabricated an engineering-scale crystallizer and have carried out continuous operation test to investigate the stability of the equipment at steady and non-steady state conditions by using depleted uranium. As for simulating typical failure events in the crystallizer, crystal accumulation and crystal blockage were occurred intentionally, and monitoring method and resume procedure were tried and selected in this work. As the test results, no significant phenomenon was observed in the steady state test. And in the non-steady state test, process fluctuation could be detected by monitoring of screw torque and liquid level in the crystallizer, and all failure events are proven to be recovered by appropriate resumed procedures.

Download Full-text

Thermal Hydraulic Test of Advanced Fuel Bundle With Spectral Shift Rod (SSR) for BWR: Steady State and Transient Test Results and Analysis

Volume 3: Thermal-Hydraulics; Turbines, Generators, and Auxiliaries ◽

10.1115/icone20-power2012-54469 ◽

2012 ◽

Author(s):

Takao Kondo ◽

Kazuaki Kitou ◽

Masao Chaki ◽

Yukiharu Ohga ◽

Takeshi Makigami

Keyword(s):

Steady State ◽

Water Level ◽

Simulation Analysis ◽

Spectral Shift ◽

Test Results ◽

Analysis Method ◽

Fuel Bundle ◽

State Test ◽

Shift Effect ◽

Steady State Test

Japanese national project of next generation light water reactor (LWR) development started in 2008. Under this project, spectral shift rod (SSR) is being developed. SSR, which replaces conventional water rod (WR) of boiling water reactor (BWR) fuel bundle, was invented to enhance the BWR’s merit, spectral shift effect for uranium saving. In SSR, water boils by neutron and gamma-ray direct heating and water level is formed as a boundary of the upper steam region and the lower water region. This SSR water level can be controlled by core flow rate, which amplifies the change of average core void fraction, resulting in the amplified spectral shift effect. This paper presents the steady state test with varied SSR geometry parameters, the transient test, and the simulation analysis of these steady state and transient tests. The steady state test results showed that the basic functioning principle such as the controllability of SSR water level by flow rate was maintained in the possible range of geometry parameters. The transient test results showed that the change rate of SSR water level was slower than the initiating parameters. The simulation analysis of steady state and transient test showed that the analysis method can simulate the height of SSR water level and its change with a good agreement. As a result, it is shown that the SSR design concept and its analysis method are feasible in both steady state and transient conditions.

Download Full-text