Recent in situ observations during Critical Ionization Velocity (CIV) experiments under the CRIT project produced puzzling results, apparently at odds with current ClV theories. It is shown that incorporation in the theory of lower hybrid wave (LHW) instabilities of strong turbulence and finite size effects results in reconciliation of the theory with the observations.

This paper deals with the threshold radius that warrants the use of single restraining rail for transit and railroads. Different railways use different threshold radius from 91m to 365m to provide restraining rail. These threshold figures are probably experience driven choices. The need for restraining rail may be related to a so-called derailment alarm coefficient of 1.2 sustained over 2m leng...

in this paper effects of fractured sleepers on rail track vibration under moving wheelset have been investigated. two parallel rails of the track have been modeled as euler-bernoulli beams on elastic points as rail pads. also sleepers have been modeled as visco-elastic euler-bernoulli beams. it is assumed that, some sleepers under the rail track have been fractured and modeled by two beams. the...

this paper proposes a low voltage (±0.55v supply voltage) low power (44.65µw) high common mode rejection ratio (cmrr) differential amplifier (d.a.) with rail to rail input common mode range (icmr), constant transconductance (gm) and enhanced frequency performance. its high performance is obtained using a simple negative averaging method so that it cancels out the common mode input signals at th...

the track stiffness experienced by a train will vary along the track. sometimes the stiffness variation may be very large within a short distance. one example is when an unsupported sleeper is hanging in the rail. track stiffness is then, locally at that sleeper, very low. at insulated joints the bending stiffness of the rail has a discontinuity implying a discontinuity also of the track stiffn...

July-August 2012 Imagine you fly home from vacation with your one-and-ahalf-year-old son who is traveling for free as a “lap child.” In the airport parking lot, you put him into his forwardfacing car seat, where he sits much more contentedly than he did in the rear-facing one that was mandatory until his first birthday. After he falls asleep on the way home, you transfer him to his crib without...

Wheel/rail contact simulation is one of the most complicated problems in the modeling of railway vehicles. The wheel/rail interaction plays a unique role in rail vehicle dynamics. In this paper, the dynamic response of the wheel on irregular rail track is analyzed with analytical approach using the method of Multiple Scales (MMS). The Hertzian contact theory is used to obtain the relationshi...

Abstract: To ensure the rail transportations safety, evaluation of fatigue behavior of the rail steel is necessary. High cycle fatigue behaviour of a rail steel was the subject of investigation in this research using fracture mechanics. Finite element method (FEM) was used for analyzing the distribution of the stresses on the rail, exerted by the external load. FEM analysis showed that the ...