End carriage of a railway vehicle and associated railway vehicle

Abstract

The invention concerns an end carriage (10) of a railway vehicle, extending between a first free end (10A) and a second end according to a longitudinal axis (X), the end carriage (10) also comprising an upper wall (14) and an underframe (16) opposed to each other according to an elevation axis (Z) perpendicular to the longitudinal axis (X). The end carriage (10) comprises an air path device (22) configured to allow the circulation of air from an inlet (24) to an outlet (26), the inlet (24) being defined in the first free end (10A) and is configured to suck air according to the longitudinal axis (X), the outlet (26) being defined in the underframe (16) and is configured to blow air according to the elevation axis (Z).

Description

[0001] The present invention concerns an end carriage of a railway vehicle.

[0002] A railway vehicle, notably a high-speed railway vehicle, is subject to aerodynamic drag effect opposing the displacement of this railway vehicle.

[0003] In particular, cavities, such as bogie cavities, are one of the main contributors to aerodynamic drag.

[0004] In order to reduce this drag effect, in the state of the art, it is already known to install drag mitigation devices, such as covers or spoilers covering these cavities.

[0005] However, such devices are not entirely satisfactory.

[0006] Indeed, they increase the weight of the vehicle.

[0007] Moreover, these devices restraint the accessibility to the equipment arranged in the corresponding cavity and thus complicate the maintenance of these elements.

[0008] Notably the object of the invention is to provide a solution for reducing the aerodynamic drag effect on cavities present on railway vehicles, without restraining the accessibility to the equipment arranged in the cavities, while being cost-, weight- and space-saving.

[0009] For this purpose, the object of the invention is notably an end carriage of a railway vehicle, extending between a first free end and a second end intended to be connected to another carriage of the railway vehicle, the first free end and the second end being opposite according to a longitudinal axis, the end carriage also comprising an upper wall and an underframe opposed to each other according to an elevation axis perpendicular to the longitudinal axis.

[0010] The end carriage comprises an air path device configured to allow the circulation of air from an inlet to an outlet, the inlet being defined in the first free end and is configured to suck air according to the longitudinal axis, the outlet being defined in the underframe and is configured to blow air according to the elevation axis.

[0011] This expulsion of air at the outlet has the effect of modifying the behavior of the air between the underframe of the end carriage and the rails, thus allowing to minimize the aerodynamic drag effect.

[0012] An end carriage according to the invention may further include one or several of the following features, taken alone or according to any technically conceivable combination: The end carriage comprises a lower housing for a bogie, the outlet being defined, in the longitudinal axis, between the lower housing and the first free end. The inlet is a slit. The inlet is defined at a high-pressure area of the first free end. The air path device comprises at least a first portion extending parallel to the longitudinal axis from the inlet and a second portion extending parallel to the elevation axis and leading into the outlet. The air path device comprises a third portion connecting the first portion and the second portion. The air path device comprises a pressurized volume driving an airflow from the high-pressure area at the inlet towards a low-pressure area, through the outlet. The end carriage does not comprise any means for circulating air inside the air path device.

[0013] The invention also relates to a railway vehicle, including at least one end carriage as described above.

[0014] In an advantageous embodiment, the end carriage is the front-end carriage of the railway vehicle.

[0015] The invention and its advantages will be better understood upon reading the following description, which is given solely by way of non-limiting example and with reference to the appended Figures, in which: Figure 1 is as schematic and partly representation of an end carriage according to a first embodiment of the invention; and Figure 2 is as schematic and partly representation of an end carriage according to a second embodiment of the invention.

[0016] Figures 1 and 2 both show an end carriage 10 intended to equip a railway vehicle, in particular a high-speed railway vehicle.

[0017] The railway vehicle is for example configured to move in a circulation direction D along a longitudinal axis X, for example on rails extending also along the longitudinal axis X.

[0018] In the exemplar embodiments illustrated on the Figures, the end carriage 10 is thus a front-end carriage.

[0019] The end carriage 10 extends, in the longitudinal axis X, between a first free end 10A, and a second end (not visible on the Figures) intended to be connected to another carriage of the railway vehicle.

[0020] The first free end 10A and the second end are opposite according to the longitudinal axis X.

[0021] In particular, the first free end 10A corresponds to the front end of the railway vehicle.

[0022] The first free end 10A comprises in particular a high-pressure area 11, for example receiving the highest pressure of the end carriage 10, when the vehicle is moving in the circulation direction D.

[0023] This pressure is for example induced by the airflow F generated along the longitudinal axis X in a second direction opposite to the circulation direction D.

[0024] This pressure at the high-pressure area 11 is for example greater than 4 kPa, when the vehicle is moving to a speed greater than 300 km / h in standard conditions.

[0025] For example, the end carriage 10 has a general aerodynamic shape, notably having, conventionally, a profile comprising a tip 12 at the first end 10A. Such a tip 12 is also called a "nose" of the end carriage 10.

[0026] More precisely, the tip 12 defines the high-pressure area 11, corresponding for example to the most extreme point according to the longitudinal axis X.

[0027] The end carriage 10 also comprises an upper wall 14 and an underframe 16 opposed to each other according to an elevation axis Z perpendicular to the longitudinal axis X.

[0028] In the preferred embodiment illustrated on the Figures, the end carriage 10 moreover comprises a lower housing 18 for a bogie 20.

[0029] More precisely, the lower housing 18 is a cavity defined in the underframe 16 of the end carriage 10.

[0030] In particular, the lower housing 18 is defined in proximity to the first end 10A. In other words, in the case when the end carriage 10 includes several lower housings for bogies, the lower housing 18 considered in the present description is the closest one to the first end 10A.

[0031] The end carriage 10 comprises an air path device 22 configured to allow the circulation of air (represented by the arrows in the Figures) from an inlet 24 to an outlet 26.

[0032] As shown on the Figures, the inlet 24 is defined in the first free end 10A and is configured to suck air according to the longitudinal axis X, in particular in the second direction opposite to the circulation direction D when the railway vehicle is moving.

[0033] In particular, the inlet 24 is an opening defined in the first free end 10A configured to draw a part of the airflow F generated along the longitudinal axis X in the second direction opposite to the circulation direction D when the railway vehicle is moving in the circulation direction D.

[0034] More preferably, the inlet 24 is a slit, and in particular, a narrow opening extending in the first free end 10A according to a transversal axis Y perpendicular to the longitudinal axis X and to the elevation axis Z.

[0035] For example, the inlet 24 has a cross-section, with a length measured along the transversal axis Y comprised between 80 cm and 120 cm and a width measured along the elevation axis Z comprised between 4 cm and 6 cm.

[0036] In an advantageous manner, the inlet 24 is defined at the high-pressure area 11 of the first free end 10A, in order to draw the airflow towards the underframe. The high pressure at the high-pressure area 11 allows accelerating the airflow F sucked in the inlet 24.

[0037] The outlet 26 is defined in the underframe 16 of the end carriage 10 and is configured to blow air according to the elevation axis Z, in particular downwards.

[0038] In particular, the outlet 26 is an opening defined in the underframe 16 of the end carriage 10 and configured to blow the airflow leaving the air path device 22, more precisely downwards, i.e. towards the rails when the railway vehicle is moving.

[0039] The outlet 26 is preferably defined, in the longitudinal axis X, between the lower housing 18 and the first free end 10A.

[0040] In a first embodiment shown in Figure 1, the air path device 22 is notably a continuous pipe extending from the inlet 24 to the outlet 26.

[0041] In particular, the air path device 22 is configured, such that the cross-section area at the inlet 24 allows sufficient airflow rate through the outlet 26, the airflow F being blown at the outlet 26 along the elevation axis Z, in particular downwards.

[0042] As shown in Figure 1, the air path device 22 comprises for example at least a first portion 28 extending horizontally, i.e. parallel to the longitudinal axis X, from the inlet 24 and a second portion 30 extending vertically, i.e. parallel to the elevation axis Z, and leading into the outlet 26.

[0043] In the exemplar embodiment shown on the Figure 1, the air path device 22 comprises a third portion 32 connecting the first portion 28 and the second portion 30, in particular for deviating the airflow inside the air path device 22.

[0044] The air path device 22 is preferably hollow, in order to allow the circulation of the airflow from the inlet 24 to the outlet 26.

[0045] In particular, no component is arranged inside said air path device 22.

[0046] The circulation of air from the inlet 24 to the outlet 26 is performed in a natural way as will be described hereafter.

[0047] In other words, the end carriage 10 does not comprise any means for circulating air inside the air path device 22, such as fans for example.

[0048] When the railway vehicle is moving in the circulation direction D along the longitudinal axis X, the airflow F is for example generated along the longitudinal axis X in the second direction opposite to the circulation direction D.

[0049] This airflow F comes then into contact with the first free end 10A of the end carriage 10, in particular with the high-pressure area 11.

[0050] As shown on Figure 1, a part of the airflow F is thus sucked inside the air path device 22 by the inlet 24, and then preferably flows inside the air path device 22, and more particularly inside its first portion 28, along the longitudinal axis X in the second direction.

[0051] For example, the airflow F is thus deviated inside the air path device 22, for example by its third portion 32, such that the airflow F flows along the elevation axis Z, in particular downwards, more precisely inside the second portion 30.

[0052] Then, the airflow F is blown on the outlet 26 along the elevation axis Z, in particular downwards, more particularly towards the rails.

[0053] This airflow F is preferably blown underframe, in particular upstream the lower housing 18.

[0054] By "upstream", it is meant here before the lower housing 18 according to the direction of the generated airflow, i.e. the second direction opposite to the circulation direction D.

[0055] A second embodiment is shown in Figure 2. This embodiment differs from the first embodiment of Figure 1, in that the air path device is not a continuous pipe extending from the inlet 24 to the outlet 26.

[0056] In particular, in the second embodiment shown in Figure 2, the air path device 22 comprises a pressurized volume 25, for example a coupler cavity as illustrated in Figure 2, driving an airflow from the high pressure area 11 at the inlet 24, towards a low pressure area 34, through the outlet 26.

[0057] The low-pressure area 34 has a lower pressure than the high-pressure area 11. The low pressure 34 is in particular located, at the outlet 26, between the underframe 16 of the end carriage 10 and the rails.

[0058] The air path device 22 is configured, such that the cross-section area at the inlet 24 allows sufficient airflow rate through the outlet 26.

[0059] The pressurized volume 25, for example the coupler cavity, is more particularly delimited by a wall 33, extending according to the elevation axis Z.

[0060] As shown on Figure 2, the wall 33 extends preferably at proximity of the outlet 26. For example, the bottom of the wall 33 defines an edge of the outlet 26.

[0061] The pressurized volume 25 is pressurized by the airflow F coming in the longitudinal axis X, entering through the inlet 24 which is located at the high pressure area 11.

[0062] The pressurized volume 25 configured such that the air in the pressurized volume 25 flows parallel to the wall 33, in particular downwards, and towards the outlet 26.

[0063] The circulation of air from the inlet 24 to the outlet 26 is performed in a natural way, from the high-pressure area 11 to the low-pressure area 34, as will be described hereafter.

[0064] In other words, the end carriage 10 does not comprise any means for circulating air inside the air path device, such as fans for example.

[0065] When the railway vehicle is moving in the circulation direction D along the longitudinal axis X, the airflow F is for example generated along the longitudinal axis X in the second direction opposite to the circulation direction D.

[0066] This airflow F comes then into contact with the first free end 10A of the end carriage 10, in particular with the high-pressure area 11.

[0067] As shown on the Figure 2, a part of the airflow F is thus sucked inside the air path device 22 by the inlet 24, and then preferably flows inside the pressurized volume 25.

[0068] For example, due to the pressure difference between the high pressure area 11 and the low pressure area 34, the airflow F thus flows towards the low pressure area 34 and thus towards the outlet 26.

[0069] Preferably, the wall 33 deviates the airflow F inside the pressurized volume 25, such that the airflow flows along the elevation axis Z, in particular downwards.

[0070] Then, the airflow is blown on the outlet 26 along the elevation axis Z, in particular downwards, more particularly towards the rails.

[0071] This airflow is preferably blown underframe upstream the lower housing 18.

[0072] The advantage of this second embodiment compared to the first embodiment is that there is no additional component to the vehicle, and thus no additional weight and cost.

[0073] For both embodiments, the expulsion of air at the outlet 26 has the effect of modifying the behavior of the air (velocity field) between the underframe 16 of the end carriage 10 and the rails, in particular near the lower housing 18.

[0074] More particularly, the blown airflow creates an air spoiler deviating a flow of air arriving on the bogie 20, when the railway vehicle is moving. The pressure on the bogie 20 and on the lower housing 18 is thus minimized, thus reducing the aerodynamic drag effect.

[0075] The air path device 22 does not restrain the accessibility to the equipment arranged for example in the lower housing 18, thus simplifying the maintenance of said equipment.

[0076] Furthermore, since no means of circulating air is used, the reduction of the aerodynamic drag effect is performed without electricity consummation, and in a cost-, weight- and space-saving way.

[0077] It will be noted that the invention is not limited to the embodiment described earlier, but may have diverse additional alternatives.

Claims

1. An end carriage (10) of a railway vehicle, extending between a first free end (10A) and a second end intended to be connected to another carriage of the railway vehicle, the first free end (10A) and the second end being opposite according to a longitudinal axis (X), the end carriage (10) also comprising an upper wall (14) and an underframe (16) opposed to each other according to an elevation axis (Z) perpendicular to the longitudinal axis (X), characterized in that the end carriage (10) comprises an air path device (22) configured to allow the circulation of air from an inlet (24) to an outlet (26), the inlet (24) being defined in the first free end (10A) and is configured to suck air according to the longitudinal axis (X), the outlet (26) being defined in the underframe (16) and is configured to blow air according to the elevation axis (Z).

2. The end carriage (10) according to claim 1, in which the end carriage (10) comprises a lower housing (18) for a bogie (20), the outlet (26) being defined, in the longitudinal axis (X), between the lower housing (18) and the first free end (10A).

3. The end carriage (10) according to claim 1 or 2, in which the inlet (24) is a slit.

4. The end carriage (10) according to any of the preceding claims, in which the inlet (24) is defined at a high-pressure area (11) of the first free end (10A).

5. The end carriage (10) according to any of the preceding claims, in which the air path device (22) comprises at least a first portion (28) extending parallel to the longitudinal axis (X) from the inlet (24) and a second portion (30) extending parallel to the elevation axis (Z) and leading into the outlet (26).

6. The end carriage (10) according to claim 5, in which the air path device (22) comprises a third portion (32) connecting the first portion (28) and the second portion (30).

7. The end carriage (10) according to any of the claims 1 to 4, in which the air path device (22) comprises a pressurized volume (25) driving an airflow from the high-pressure area (11) at the inlet (24) towards a low-pressure area (34), through the outlet (26).

8. The end carriage (10) according to any of the preceding claims, in which the end carriage (10) does not comprise any means for circulating air inside the air path device (22).

9. Railway vehicle comprising an end carriage (10) according to any of the preceding claims.

10. Railway vehicle according to claim 9, in which the end carriage (10) is the front-end carriage of the railway vehicle.

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