I determined the natural frequencies of the headlight design for electric locomotive VL by software system of the finite-element analysis ANSYS. The obtained values of the natural frequencies are compared with the frequencies of the periodic vibrations experienced by the railway rolling stock. The analysis reveals the vibration frequencies determining the period of the trouble-free operation of the headlight.
The main sources of vibration for driving railway locomotive are just a vehicle,
wheels, rails and railway track. According to the Resolutions of 15.07.2011, N 710
"On the adoption of the technical regulations of the Customs Union" ("On the safety
of the railway rolling stock", "On the safety of the high-speed railway transport", and
"On the safety of the railway infrastructure") [
A railway locomotive undergoes periodic and random vibrations. The reasons of the excitation of the periodic vibrations are the deflection of the rail track moving along with the movement of the train and the support system; the discrete structure of the rail support (the distance between the axes of sleepers); the discreteness of the effect on the object due to the distance between the axes of wheel pairs and bogies; the breaks of the rail track (at the diverters, at the blind crossings of the railway track, at the junctions of the rails, and so on. 3 Fig. 1. – The causes of the excitation of periodic vibrations of a railway locomotive: 1 is the distance between the support elements of the railway track; 2 is the distance between the wheel pairs of the bogie; 3 is the distance between the adjacent bogies of adjacent railway cars; 4 is the distance between the bogies of a railway car; 5 is the distance between railway cars
The random vibrations are the noise emitted by the rattling objects (panes, lamps, conjugations of a shaft-hole with the loose fit and so on). The vibration is transmitted, being changed through the rail tracks on their support and further into the ground, the frame and the body of a locomotive, the surface roughness of a wheel rim and when riding the rail, causing at the same time the re-radiated noise. The re-radiated noise of the object of the exposure is observed in the frequency range from about 16 to 250 Hz in accordance with the Resolution. The description of the noises is quantitatively associated with certain difficulties, so they will not be considered.
When analyzing the vibration and the noise, it should be considered that the vibration sources, their pathways of the propagation and the objects of their effect depend on many factors, namely, according to the Resolution: the geometry of the rail track, the characteristics of the rolling stock (its length, a wheel profile, a wheel diameter, the roughness and surface defects when riding a wheel, the system of the wheel suspension, wheels with elastic elements and etc.), the characteristics of rails, elements of the rail track, and others. The vibration source, the pathway of the vibration propagation and the object of the effect are shown schematically in Fig. 2. 1. The definition of the boundaries of the range of possible fluctuations of a railway locomotive
The frequency of the periodic vibrations depends on the speed of a railway locomotive. Table 1 summarizes the possible oscillation frequencies depending on the speed of the movement (VM) applied to an electric locomotive VL series. The phenomena of interference, the vibration diffraction are not taken into account, i.e. the locomotive is considered as one rigid body.
A locomotive, ahead of the next train, experiences the vibrations generated not only by the train and by the railroad track, but the vibrations generated by the bogies of the driven railway cars. The vibration oscillation of each railway car is transmitted by the rails as through the waveguides with the velocity of the sound in metals (22000 km/h). The vibration oscillation caused by the deflection of the rails in the intervals between the sleepers, results in the formation of a surface (Rayleigh) wave on the ground surface. These waves formed by the railway cars of the rolling stock, provided the hard ground, can catch up and overtake a locomotive, that in turn can result in the change of the oscillation spectrum of the rolling stock as well as of the locomotive. If the high-speed train moves along the rail track, provided the soft ground, then, the velocity of its movement can exceed the speed of the propagation of a surface (Rayleigh) wave in the ground. This creates a high level of vibration, just as the flight of a supersonic aircraft is accompanied by the sonic boom (based on the Solution).
Thus, the vibrations of the entire rolling stock participate in the formation of the oscillation spectrum of the locomotive vibrations. The range of the locomotive Name of parameters of railway track and suspension of an electric locomotive Distance between support elements of the track, m Distance between wheel pairs of the bogie, m Distance between adjacent bogies of adjacent railway cars, m Distance between bogies of a railway car, m Distance between railway cars, m Length of rails, m
Geometric dimensions
and sources of
information
0,501 -0,632
(GOST R 51248-99;
GOST 78-2004;
GOST 9238-83;
GOST 10629-88, [
A headlight of an electric locomotive VL series must meet certain requirements. A lamp should be installed along the longitudinal axis of the symmetry of a locomotive. The axial beam of the headlight should be directed parallel to the horizontal plane of the road. The nominal axial intensity of the lamp should be (6.4-9.6)∙105 cd. The closed circuit of the lamp must provide the possibility of powering up the bright light, providing the nominal axial force of the light and the dim light, providing the power of the light within (0.7-1.2)∙105 cd in accordance with GOST 12.2.056-81.
The test method for measuring the axial light intensity of the headlight is to
determine the light intensity by measuring the light with simultaneous measuring the
voltage of the light source in accordance with the regulations of 2000, agreed by the
contact group 28/01/2010 V1.00, about the preservation of technical and
interoperability of the rail system of the rail road of 1520 mm and 1435 mm at the
border of the CIS and the EU, as well as in accordance with [
To achieve the nominal axial force of the light of the headlight and to achieve the
angles of ray scattering [
To determine the natural frequencies of a headlight in the software environment
ANSYS the 3D model is used that is obtained in [
For the frequencies above the maximum frequency of the periodic vibrations (f = 110.9 Hz Tab. 1), the maximum deformations are at the end of the glass bulb of the lamp SL. A glass reflector in this case is deformed slightly (Fig. 4).
1. The destruction of a glass reflector is in the range of the frequencies of the
vibration oscillation [22.368 – 62.595] Hz.
2. The destruction of a glass lamp SL is at the frequencies greater than 95.998 Hz.
3. The increase in the resource of the lamp SL can be achieved by changing the
design of a headlight, namely by using the high-frequency dampers.
4. The substantial increase in the resource of a headlight can also be achieved by
replacing an incandescent lamp by the high power light emitting diodes (LEDs) using
new methods and the necessary software for designing such a lighting device [