Static and modal numerical analyses for the roof structure of a railway freight refrigerated car

Vatulia

et al. 2021

EEJET

This paper reports a study into determining the dynamic load and strength of the bearing structure of a covered freight car under operational modes. A feature of the freight car's bearing structure is that the girder beam has a closed cross-section. To reduce the dynamic load of the frame, the girder beam is filled with a material with viscoelastic properties. Such a solution could contribute to the transformation of the kinetic energy of impact (due to jerk, stretching, compression) into work of viscoelastic friction forces, and, consequently, to reducing the load on the bearing structure. To substantiate the proposed improvement, the dynamic load on the bearing structure of a covered freight car was mathematically modeled. The calculation was performed for the case of joint impacts at shunting. The study was carried out in a flat coordinate system. It was established that the maximum accelerations acting on the bearing structure of a covered freight car were about 37 m/s2. The calculated acceleration value is 3.2 % lower than that obtained for the bearing structure of a covered freight car without filler. The results of calculating the strength of the load-bearing structure of a covered freight car are given. In this case, a finite-element method was applied. The maximum equivalent stresses occur in the zones of interaction between the girder beam and the pivot beams, and amount to 319.5 MPa, which is 8 % lower than permissible. The calculation was also performed regarding other operational modes of loading the freight car's bearing structure. The model of the dynamic load on the bearing structure of a covered freight car was verified according to the F-criterion. The research reported here could contribute to designing innovative rolling stock structures, thereby improving the efficiency of their operation.

“…The results of calculating the strength of the bearing structure of a covered freight car are reported in [12]. The calculation was implemented by a finite-element method.…”

Section: Literature Review and Problem Statementmentioning

confidence: 99%

“…The above review of literary sources [9][10][11][12][13][14][15][16][17][18] allows us to conclude that the issue related to reducing the load on the bearing structure of a covered freight car under operational load modes requires further research and development.…”

Section: Literature Review and Problem Statementmentioning

confidence: 99%

Defining patterns in the dynamic load and strength of the bearing structure of a covered freight car with a filler in the girder beam

Panchenko

Vatulia

et al. 2021

EEJET

“…The static and modal numerical analysis of the structure of a covered rail wagon is reported in [5]. The strength was calculated using a method of finite elements.…”

Section: Literature Review and Problem Statementmentioning

confidence: 99%

“…An analysis of references [1][2][3][4][5][6][7][8] allows us to conclude that up to now the issue of determining the patterns in the dynamic load and durability of the load-bearing structures of covered wagons while firing from them has not been paid proper attention to. This may cause damage to the typical load-bearing structures of wagons when they are used for military strategic purposes.…”

Section: Literature Review and Problem Statementmentioning

confidence: 99%

Determining the dynamic loading and strength of the bearing structure of a covered wagon when firing from it

Lovska

Kudelya

et al. 2020

EEJET

The bearing structure of a covered rail wagon has been improved to enable firing from it at motion. The covered wagon of model 11-217 was chosen as a prototype. To enable firing in the vertical plane, it has been proposed to use a sliding roof, which consists of shutters that move by means of a pneumatic or hydraulic drive. To accommodate military equipment inside the covered wagon, its frame is equipped with supporting sectors. Mathematical modeling was performed in order to determine the dynamic load on a covered rail wagon when firing from it. The mathematical model was solved in the Mathcad software package. We have established the dependence of the accelerations of the bearing structure of a covered rail wagon on the recoil force induced by the combat equipment that it hosts. It has been found that in order to maintain the dynamics indicators within acceptable limits, combat equipment should have a maximum recoil at a shot of about 3.2 kN. The maximum accelerations that act on the bearing structure of a covered wagon in a vertical plane are about 6 m/s 2. In the zones of interaction between the body and bogies, the maximum accelerations are about 9.5 m/s 2 and the accelerations of bogies are 10 m/s 2. To reduce the dynamic load on the bearing structure of a covered rail wagon, it has been proposed to use a viscous connection between the supporting sectors and frame. We have determined the dependence of accelerations on the coefficient of viscous resistance between the supporting sectors and the bearing structure of a wagon. It has been established that taking into consideration the use of a viscous connection between the supporting sectors and frame makes it possible to reduce the dynamic load on a wagon at least by 15 %. The basic indicators of strength for the bearing structure of a covered rail wagon when firing from it have been determined. We have derived the dependence of the maximum equivalent stresses in the bearing structure of a covered wagon on the recoil force of combat equipment. The maximum equivalent stresses at a recoil force of 3.2 kN arise in the console part of the girder of a covered wagon and are about 300 MPa. The maximum displacements were registered in the area where the front stops of the auto-coupling are arranged; they are equal to 2.9 mm. The maximum deformations amounted to 6.98•10-3. Modal analysis of the bearing structures of a covered rail wagon has been carried out. It has been determined that the values of the oscillation natural frequencies are within the permissible limits. Our study will contribute to the construction of innovative rolling stock for the transportation of military equipment and for firing at motion

“…The computer modelling of strength for the carrying structure of a wagon is given in study [6]. The current work determined dislocation fields of the maximum equivalent stresses and displacements for the carrying structure of a wagon.…”

Section: Introductionmentioning

confidence: 99%

Dynamic Load and Strength Determination of Carrying Structure of Wagons Transported by Ferries

Lovska

Píštěk

et al. 2020

JMSE

A rapid development of economic relations between states has required an introduction of combined rail/ferry transportation. A feature of this type of transportation is the possibility of wagons traveling by sea on specially equipped ships—railway ferries. However, the transportation of wagons by sea is accompanied by damage to their structures. This follows from the fact that the wagons are not adapted to this type of transportation. In addition, the design of wagons does not consider the loads that can act on them during transportation by sea. In this connection, it is important to study the dynamic loading and strength of wagons during their transportation by sea. The current work investigated into dynamic load on the carrying structure of wagons transported by ferries using mathematical and computer modelling and defined accelerations on the wagon body. The adequacy of the models was checked with an F-test. The results of strength calculation for the carrying structure of a wagon made it possible to conclude that a typical fixation diagram does not provide the admissible range of strength parameters. The current work proposed an improved fixation diagram for cars on the deck with the viscous binder. The solution was substantiated by the results of the mathematical modelling of dynamic forces, strength, and stability of the carrying structure of a wagon on the deck. The results of the work will contribute to the creation of recommendations for the transportation of wagons on ferries. The research can contribute to safe transportation of wagons by ferries, and higher efficiency of the combined transportation