EP2681094B1 - Rail vehicle with receptacle space underneath the floor - Google Patents

Description

The invention relates to a rail vehicle, in particular a tensile part (eg a carriage or power train) of a high-speed train. The invention further relates to a method for producing a rail vehicle, in particular a tensile part of a high-speed train. The rail vehicle has a body with a bottom that limits a body space for transporting people and / or cargo down. Below the bottom of a receiving space for receiving devices of the vehicle is formed, wherein the receiving space has at least one air inlet opening and at least one air outlet opening. The receiving space is particularly in the height range of bogies of the rail vehicle.

The invention relates in particular to a rail vehicle according to the features of the preamble of independent claim 1 and to a method for producing such a rail vehicle according to the features of the preamble of independent claim 7.

For the operation of rail vehicles, various facilities are needed, such as traction motors for traction motors and other electrical loads, voltage transformers, battery chargers, control devices for controlling other equipment, compressed air compressors of the brake system and electrical distributors. These devices are preferably arranged at the bottom of the floor, especially in cars for high-speed trains.

WO 2010/026049 A1 describes a rail vehicle with a cooling arrangement for arranged in an underfloor area components that are cooled via an associated radiator. The cooling arrangement has at least one first inlet opening for fresh air to be used as cooling air and at least one fan for guiding the cooling air in the direction of at least one of the components. The at least one first inlet opening is arranged in the underfloor area. The cooling arrangement also has at least one with the fan fluidly connected second inlet opening for use as cooling air deadline air, which is arranged above side skirts of the rail vehicle and connected via an air duct with the underfloor area. In a specific embodiment, a bottom side of a railcar is fluidly sealed by means of a floor pan, so that above the floor pan cooling air flows can be performed. The floor pan continues at its outer edges in side skirts of the trainset. A power converter cooling system, which is provided within the floor pan and in the longitudinal direction of the railcar approximately in the middle, draws cooling air for cooling the power converter, which is arranged above the floor pan. Further, traction motor fans draw air for cooling the traction motors provided in bogies, and below the cooling system, an air outlet is provided in the otherwise sealed tray, which serves as an outlet for the cooling air flow of the cooling system.

According to the cited document, at least part of the cooling air passes via a channel from an inlet opening to the underfloor arranged cooling arrangement.

The arrangement of the above-mentioned devices below the carbody floor (i.e., underfloor) requires stable attachment of the facilities. In addition, the facilities must be reliably protected against contamination, in particular by dirt particles in the ambient air. Furthermore, the devices are also against mechanical impact, for. As whirled stones to protect.

It is customary to hang the units at the bottom of the car body. In order to avoid contamination by particles in the cooling air, the devices can be housed in a separate housing and particles are filtered out of the cooling air, fed through a channel and introduced into the housing. A corresponding fan, which causes the cooling air flow is typically located within, at the beginning or at the end of the air duct.

Underground devices can be of varying difficulty. For example, a voltage transformer may weigh several tons while an electric distributor weighs only a few kilograms. In order not to affect the driving characteristics of the car, the weight should be balanced, ie it should not, for example, all the particularly heavy equipment in the front of the car and all light equipment in the rear of the car be arranged. Also in the direction transverse to the direction of travel, the particularly heavy equipment should be located with its center of gravity in the middle of the car body and should be as possible, the center of gravity of the underfloor devices located in the middle of the car body. Since the devices but also have very different volumes and are to be connected, for example, to cables or liquid lines, the mounting location for the individual devices can not be chosen freely. In many cases, at least a certain local area must be maintained to accommodate a particular device, or additional leads or cables may be accepted. In addition, the production of connections of the equipment immediately below the bottom of the car body is difficult. In the production of the car, the assembly can be facilitated by the fact that the devices are first attached and connected in the underfloor area and only then other facilities and parts of the car are mounted. In the later maintenance and repair of equipment, however, the effort for loosening and restoring the connections and disassembly of the devices is difficult.

In addition, even the arrangement of particularly heavy equipment below the ground contributes to the fact that the overall center of gravity of the car is above the rails. With a bracket on the underside of the floor, which allows a lower arrangement of heavy equipment, the center of gravity can be lowered. However, such a stable additional bracket increases the overall weight of the car.

DE 42 23 647 A1 describes a device for cooling of electronic units of a power supply system for passenger cars where the power supply system is housed as an underfloor device in a delimiting the car floor and two aprons space, the electronic units are each arranged along a longitudinal side of the underfloor device. The electronic units are each equipped with a heat sink, the cooling ribs protrude from the frame structure of the underfloor device, and that the underfloor device includes a cooling air duct system, whereby the cooling air is sucked under the car floor above the underfloor device and exits again below the cooling fins of the electronic units from the underfloor device ,

EP 1 095 836 A2 discloses a rail vehicle with an underfloor container for electrical components of the rail vehicle, which is modularly divided into a plurality of individual containers which are mechanically connected to each other and thermally connected in series for the purpose of cooling. In a first single container, a fan is arranged. On opposite sides of the first single container is ever another (second and third) single container available. On a third side of the single container a fourth single container is provided. The individual containers have ventilation openings and are induced by the fan flows through cooling air.

It is an object of the present invention to provide a rail vehicle and a method for producing a rail vehicle, can be cooled by the underfloor facilities of the rail vehicle in a simple manner and yet reliable, with pollution by particles contained in the ambient air to be avoided.

The appended claims define the scope of protection.

According to a basic idea of the present invention, at least one device to be cooled is arranged underfloor in a receiving space, which is secured against the ingress of dirt and which also has outer surfaces which are the devices Protect against mechanical damage in the receiving space. Alternatively, at least one device to be cooled (preferably underfloor) is / are arranged outside the receiving space, but it is cooled with air from the receiving space. In the receiving space in this case is at least one device that does not have to be cooled by an airflow generated by a radiator. In particular, at least one air inlet opening of the receiving space is a filter device for filtering particles out of the ambient air passing through the inlet opening. The filter device may consist of several filters, for. B. a gravity filter and a particle filter of the filter class G3 (ie, a filter with an average degree of separation of 80 to 90% for particles, eg., Particles, which are greater than 10 microns) have. This ensures that air purified via the at least one inlet opening enters the receiving space. Since the receiving space is otherwise also secured against ingress of dirt, in particular through walls and receiving space floor is located during operation of the rail vehicle only in this way purified air within the receiving space.

According to a further basic idea of the present invention, it is possible to dispense with air supply channels within the receiving space. Rather, air can be sucked in at any point within the receiving space and from any areas of the receiving space and a cooling air flow for cooling at least one to be cooled Device are generated. The air in the receiving space therefore forms a reservoir for already cleaned cooling air.

The elimination of cooling air ducts to draw in air from the environment simplifies the construction and assembly and reduces the dependence on suitable conditions outside the rail vehicle. For example, during operation outside the rail vehicle, pressure fluctuations may occur (eg, due to vehicle speed and cross winds) which, in the case of an air supply duct, act directly on the cooling air flow. Corresponding fluctuations of the cooling air flow within the receiving space are at least largely avoided by a large reservoir of already cleaned cooling air.

The object is thus achieved by the features of the characterizing part of the independent claims.

It is preferred that the device in the receiving space or at least one of the arranged in the receiving space facilities is a device to be cooled and the fan is arranged so that it accelerates during operation air from the main air volume and the air flows to the device to be cooled and flows from the device to be cooled through at least one air outlet opening from the receiving space into the environment.

In addition to the main air volume, in particular a volume can be located within the receiving space, which is used for discharging the heated cooling air into the environment via the at least one air outlet opening. Furthermore, it is also possible to supply unused and therefore not yet heated cooling air from the receiving space traction motors, which are located outside of the receiving space in an adjacent bogie. The feeder occupies part of the volume in the receiving space. In this case, the feed preferably begins at a cooler which accelerates the air from the main volume of air and thereby pressurized and fed by the feed to the traction motor or traction motors. These volume areas therefore also contain cooling air, which however is not available for sucking and cooling the arranged within the receiving space facilities.

There may be additional volume areas of the receiving space in which there is air, but does not belong to the main volume of air. For example, air may be permanently trapped within housings. However, it is preferred that the main volume of air not only contain most of the air in the receiving space (ie more than 50%) but more than 70%, and more preferably more than 80% of the total volume of air. In particular, when the receiving space extends beyond the maximum possible length and maximum possible width of the space available below the body floor space, created in this way a very large main air volume and therefore a particularly large reservoir for already cleaned cooling air is formed.

At least one fan is arranged in the receiving space, which cools at least one device to be cooled (which is also preferably arranged within the receiving space) by accelerating air from the main air volume, so that the device to be cooled is cooled becomes. In general, no additional fan is required for the same device to be cooled, and no additional fan is needed for the intake of air from the environment of the rail vehicle. Rather, the negative pressure generated by the fan suffices for air from the environment to flow in through the at least one inlet opening into the receiving space. The fan is also sufficient for the used cooling air, which has absorbed heat from the device to be cooled, to be able to flow out into the environment via the at least one outlet opening.

Preferred dimensions of air from the receiving space is used not only for cooling a device to be cooled, but for a plurality of devices to be cooled. The devices to be cooled can all be located inside the receiving space or at least one device to be cooled (eg a drive motor) can be located outside the receiving space. In both cases, preferably, each of the plurality of devices to be cooled is assigned at least one fan, d. H. There is at least one separate fan for each device to be cooled. However, several units can be combined to form a common device to be cooled, z. B. several converter units (such as traction converter, auxiliary converter and network rectifier) to a power converter device. However, it is preferred that different units not be grouped together. For example, preferably in the receiving space existing facilities, in particular a battery charger, a power converter and / or a transformer for transforming the mains voltage from an electrical supply network into an electrical voltage for the operation of a power converter, for example, alone and / or with others to be cooled and / or not to be cooled facilities in the receiving space, not combined to a common device to be cooled. Each of the fans draws cooling air from the main volume of air and creates an airflow that cools the associated device to be cooled.

The receiving space can therefore be designed in particular as large as possible. In particular, the receiving space extends over the maximum possible length, ie in Direction of travel between two bogies of a car or power car, the main air volume preferably passes over the entire length of the receiving space. Thus, a large air reservoir exists in the main air volume, with the various cooling air streams being fed to the various devices to be cooled from the reservoir. Fluctuations in the demand for cooling air for the various devices may thus at least partially compensate each other as long as they do not correlate completely in time.

Preferably, the at least one air inlet opening or at least one of the air inlet openings is formed as a recess in a side wall of the receiving space. In the recess can z. B. at least part of a filter device (s.o.) be introduced for filtering particles in the sucked air or be.

Such recesses may be provided at various suitable locations on the side wall. They require little space, unlike air ducts do not increase the weight of the rail vehicle and are easy to manufacture. Since the receiving space, in contrast to a plurality of individual, separate and mutually partitioned compartments or unlike a provided with air supply channels underfloor area has a large, continuous internal volume, is also a large outer surface for air inlet openings available. Of course, not the entire large outer surface or a substantial part of it is to be formed by air inlet openings, but rather air inlet openings of the appropriate size and number can be arranged at suitable locations of the outer surface. For example, in an engine head of a high-speed vehicle with a maximum speed of more than 300 km / h, no air inlet port may be provided in the front portion of the side walls of the accommodating space, since negative pressure may exist in this region. However, due to the air inlet openings arranged further back, air can nevertheless flow into the receiving space and also move within the receiving space into its front area if a device to be cooled is arranged there and an associated fan generates a corresponding cooling air flow.

Under the front area is in particular the front lying in the direction of travel area to understand, ie the area that is closer to the respective end of the train, for example, the locomotive or the power car. If, as is the case, for example, in a train with power cars at both opposite ends, the direction of travel is reversed, the so-called front area is located in the direction of travel further back than a rear area thereof Receiving space. However, this is harmless for effective cooling of the devices in the receiving space, since the same turbulences do not occur in the region of one end of a train as at the beginning of the train. Therefore, an inflow of air through the air inlet openings arranged at the very end of the train into the receiving space will be possible. The term "front area" in this case is to be understood in particular as a synonym for "closer to the end".

In the receiving space are distributed in the longitudinal direction of the rail vehicle over a longitudinal portion of the receiving space, a plurality of devices (in particular with a plurality of devices to be cooled) of the vehicle arranged, wherein the main air volume extends at least over the longitudinal portion and the main air volume in the longitudinal portion is continuous, ie is not divided into individual, separate and mutually partitioned compartments, and wherein in a front region of the longitudinal section, in which at least one of the devices of the vehicle is located in side walls of the receiving space no air inlet opening is present, but in a more rearwardly located area of the Longitudinal section in the side walls of the receiving space air inlet openings are arranged, can enter through the air in the main volume of the receiving space.

In particular, when the receiving space viewed in the direction of travel is at the beginning of a train, for example in a power car or a locomotive at the beginning of the train, this avoids that outside of air inlet openings in side walls of the receiving space, especially at high speeds over 250 km / h creates a negative pressure , Therefore, air can enter the main air volume at the existing rear air inlet openings, where there is no negative pressure outside. Since the main air volume is continuous, the air that has entered through the existing air inlet openings, within the longitudinal section reach into the front area and is there for cooling facilities available.

Preferably, the single air outlet opening or, if there are a plurality of air outlet openings, all air outlet openings are located in the underfloor of the receiving space, ie on the lower outer surface of the receiving space. In contrast to the air inlet openings in the side walls arise at higher speeds no air flow through the receiving space, from the air inlet openings to the air outlet openings, obstructing pressure conditions outside of the receiving space. Rather, it is created below the receiving space typically a negative pressure everywhere, so that lower air outlet openings favor the flow of air through the receiving space.

In the following, a preferred type of mechanical construction will be discussed, the various designs of the construction are particularly advantageous for the inventive design of the receiving space and the cooling of facilities.

In particular, it is preferred that the predominant part of the weight forces (preferably the total weight forces) of the at least one device to be cooled down on a substructure of the receiving space is exercised / and acts on the substructure on the car body. At least the majority of the weight forces is therefore not exerted directly on the floor of the car body interior, but indirectly through the substructure. In particular, as will be described in more detail, the substructure may have an underbody support. It is also preferred that above the at least one device to be cooled a clearance to the bottom of the car body interior exists or is formed. This clearance can be used for the main air volume and / or for additional facilities of the rail vehicle (eg cable ducts for electrical lines).
The attachment of the underbody support to supporting parts of the carbody allows the weight of at least one of the devices in the receiving space to rest on the underbody support or at least the weight of the device to be partially, preferably predominantly and more preferably fully applied to the underbody support ,

The derivation of the weight forces down for mounting considerable advantages. For example, initially the substructure can be formed, the devices and other devices to be cooled can be applied to the substructure or introduced into the substructure, and this prefabricated arrangement can then be connected to the car body. The complex assembly is facilitated because the receiving space is freely accessible from the top before connecting the substructure to the car body.

As mentioned, an underbody support may be provided as part of the substructure. At its ends, ie at the sides of the car body, the underbody support is connected to supporting parts of the car body, in particular each with a longitudinal member of the car body, which serves to transmit longitudinal forces in the longitudinal direction of the car body. In particular, therefore, in each case in a transition region between the bottom and the side walls of the car body interior are a longitudinal member for transmitting longitudinal forces extending in the longitudinal direction of the car body. In this case, the car body has at least one underbody support, which extends below the bottom of the one longitudinal member to the other side member, wherein the underbody support extends partially at a distance to the ground, so that between the underbody support and the Floor is part of the recording room.

In particular, the underbody beam has a U-shaped profile when viewed in the longitudinal direction (travel direction) of the rail vehicle, i. H. he can take a U-shaped course from one side to the opposite side. Such side members are usually in the transition region between the bottom and the side walls.

Preferably, the underbody support initially extends downwardly from the side rail and is angled or curved at a lower level than the height level of the side rails, the underbody beam transitioning, at the bend or bend, into an approximately horizontal section, which in FIG the distance to the bottom of the car body runs. On the opposite side is preferably again a bend or bend, at which the underbody carrier merges into a second, likewise from top to bottom or from bottom to top extending portion. With respect to a median plane of the vehicle, which extends in the vertical direction and also extends in the longitudinal direction of the car body, the underbody support is preferably symmetrical or at least substantially symmetrical, ie, symmetrical with the exception of fastening means with which the carrier with the side members and / or connected to the facilities in the reception room.

A guide is preferably arranged on the longitudinal carriers, by means of which a movement of one end of the underbody carrier can be guided in the longitudinal direction of the vehicle body. There is provided a fastening means by which the underbody support is selectively attachable in a plurality of different positions relative to the side rail. This makes it possible, during the first assembly of the car body or in a later remodeling, to move and fix the substructure supports in the longitudinal direction of the car body. This allows different configurations of equipment to be attached to the underbody construction. Depending on the dimensions and weight of the underfloor devices, the positions of the underbody supports can be selected and adjusted. The guide may, for example, by one or more down open C-shaped rails are realized. Alternatively, however, the upper ends of the underbody beams may be attached to another structure attached to the underside of the floor.

As already mentioned, a plurality of the underbody beams can be arranged in different longitudinal positions in the longitudinal direction of the car body and extends below the bottom of the one longitudinal beam to the other side rail in each case. For example, 5-8 such carriers may be disposed below the floor of a large capacity passenger car to accommodate the underfloor devices required for the operation of the car or train. In this case, preferably all underbody beams are located in the longitudinal section between the two bogies of the carriage. However, it is also not excluded to accommodate one or two underbody beams in the end region of the car body, that is, at the longitudinal ends of the car body. However, there is usually the clutch for coupling the car with an adjacent car, so that the space available for the underfloor devices is small.

An underbody support can be made very sturdy with relatively little weight so that it can accommodate large weight forces from underfloor devices to be placed. In addition, such a subfloor support in a simple manner with supporting parts, in particular the longitudinal members, in the transition region between the bottom and side walls are attached. This makes it possible in a simple way to derive the weight forces directly on the underbody support and the supporting parts on the bogies.

The arrangement of the facilities underfloor also facilitates the production of connections to the devices, since the connection cables and connection cables usually pass through the floor or are guided on the underside of the floor. Between devices that do not extend over the entire height of the space between the underbody support and the floor of the car body, a gap remains to the ground, so that the mounting of the terminals is facilitated. In addition, the underbody support does not require that a device be attached to a particular position in the course of the wearer. The exact position can therefore be selected taking into account other criteria. This is especially true when not only an underbody carrier, but at least two such carriers are present. In this case, additional elements may be provided which, together with the underbody beams, are parts of a substructure. Such elements will be discussed in more detail. Depending on the design of these elements, the underfloor devices can optionally be attached to the additional elements of the substructure or be arranged thereon. If a plurality of underbody beams are present, it is preferred that the space between the beams is at least partially closed by preferably plate-shaped underbody elements, wherein air outlet openings may be provided therein. For example, such a plate-shaped element may form a subfloor, which preferably extends in the horizontal direction and approximately parallel to the actual bottom of the car body. Alternatively or additionally, a plate-shaped element may form a side wall of the underfloor area. These plate-shaped elements between the underbody beams improve the aerodynamic properties of the car. If the space between the supports is only partially closed by plate-shaped underbody elements, for example, another part of the clearance may be closed by at least one device to be cooled and / or at least one device not to be cooled (eg by an outer wall of the cooling and / or not to cool device).

The plate-shaped elements may in particular be extruded plate-shaped elements in which between two sheet-like, approximately parallel areas forming the outer surfaces, a plurality of air chambers is arranged, which are separated by partitions, which in a longitudinal direction of the plate-shaped element. Such extruded plate-shaped elements may preferably be made of aluminum and are preferably bolted to underbody beams. In this case, a plurality of plate-shaped elements can be manufactured separately in the extrusion process and connected to each other before assembly to the underbody beams, in particular welded. Also, the side walls and the bottom of the car body may be at least partially made of such plate-shaped elements. If the side walls, the floor and an additional ceiling element are prefabricated, substantially plate-shaped elements, it is referred to an integral construction of the car body. The underbody beams are particularly suitable for such a car body, wherein also longitudinal beams can be made in the transition region between the bottom and the side walls in the extrusion process. However, other constructions are possible, in particular with the side members, for example conventional double T-beams, i. I-beams.

At least two in the longitudinal direction of the car body adjacent to each other underbody support may be interconnected by at least one longitudinal strut. The longitudinal strut does not have to run exactly in the longitudinal direction of the car body, but can also run diagonally. The use of longitudinal struts represents an alternative or additional measure to the use of plate-shaped connections (also referred to above as plate-shaped elements), which serve to stiffen the underbody construction. For example, if no rigid plate-like elements are used, but rather multiple longitudinal struts, the substructure can be made very stiff and light and, for example, clad only with thin, non-load-bearing elements to improve the aerodynamic properties and to seal the receiving space from the environment. Several such longitudinal struts result in a distribution of the weight forces exerted by the devices, so that such a construction is particularly advantageous when underfloor devices with very different weights are to be accommodated below the floor.

It is preferred that the at least one device to be cooled is arranged within the receiving space and is arranged at a distance from at least one side wall of the receiving space, so that a free space remains between the device and the side wall, which forms part of the main Air volume forms. Through this space, air can be distributed within the main volume of air or air can be sucked by a fan.

Fig. 1

eine dreidimensionale Ansicht eines Unterboden-Trägers,

Fig.2

den Unterboden-Träger gemäß Fig. 1, wobei der Träger an seinen gegenüberliegenden Enden jeweils mit einem Längsträger eines Wagenkastens verbunden ist

Fig. 3

eine Anordnung mit einer Mehrzahl in Längsrichtung eines Wagenkastens voneinander beabstandeten Unterboden-Trägern, die über Längsstreben jeweils paarweise miteinander verbunden sind,

Fig. 4

die Anordnung gemäß Fig. 3, wobei die Konstruktion außerdem plattenförmige Elemente aufweist, mit denen der Unterboden-Aufnahmeraum verkleidet ist,

Fig. 5

eine bevorzugte Ausgestaltung einer Befestigung eines oberen Endes eines Unterboden-Trägers zum Befestigen an zwei parallelen C-profilförmigen Schienen (nicht in Fig. 5 dargestellt),

Fig. 6

einen Querschnitt durch die Anordnung in Fig. 5, wobei das Ende des Unterboden-Trägers an den zwei C-profilförmigen Schienen befestigt ist,

Fig. 7

eine Anordnung wie in Fig. 3, wobei in dem Unterboden-Aufnahmeraum eine Mehrzahl von Einrichtungen angeordnet ist,

Fig. 8

einen Teil eines Unterboden-Trägers, an dem zwei plattenförmige Elemente befestigt sind, die sich in Längsrichtung des Wagenkastens in beide Richtungen weg von dem Träger erstrecken und einen unteren Abschluss des Unterboden-Aufnahmeraumes bilden,

Fig. 9

die Anordnung gemäß Fig. 8, ebenfalls in dreidimensionaler Darstellung aus einem anderen Blickwinkel, wobei der Unterboden-Träger und die beiden plattenförmigen Elemente vollständig dargestellt sind, und

Fig. 10

die Anordnung gemäß Fig. 8 in dreidimensionaler Darstellung, wobei der Blick auf die Unterseite der Anordnung gerichtet ist.

Fig. 11

zeigt einen Querschnitt durch einen Aufnahmeraum zur Aufnahme von zu kühlenden Einrichtungen und optional anderen Einrichtungen eines Schienenfahrzeugs, wobei der Aufnahmeraum unterhalb des in der Figur nicht dargestellten Bodens des Wagenkastens angeordnet ist,

Fig. 12

einen Querschnitt ähnlich dem in Fig. 1, wobei ein Unterboden-Träger dargestellt ist, über den das Gewicht von Einrichtungen in dem Aufnahmeraum auf den Wagenkasten abgeleitet wird, und wobei oberhalb einer Einrichtung in dem Aufnahmeraum, aber unterhalb des Wagenkasten-Bodens Kabelkanäle angeordnet sind,

Fig. 13

schematisch eine Draufsicht auf das Innere eines Aufnahmeraumes, z. B. des in Fig. 11 und Fig. 12 dargestellten Aufnahmeraumes, wobei eine Mehrzahl von kühlenden Einrichtungen, zugeordnete Lüfter und der Verlauf des Luftstroms dargestellt sind.

Embodiments of the invention will now be described with reference to the accompanying drawings. The individual figures of the drawing show:

Fig. 1

a three-dimensional view of an underbody carrier,

Fig.2

the underbody carrier according to Fig. 1 wherein the carrier is connected at its opposite ends in each case with a side rail of a car body

Fig. 3

an arrangement with a plurality of spaced apart in the longitudinal direction of a car body underbody beams, which are connected via longitudinal struts in pairs,

Fig. 4

the arrangement according to Fig. 3 wherein the construction further comprises plate-shaped elements with which the underbody receiving space is covered,

Fig. 5

a preferred embodiment of an attachment of an upper end of an underbody support for attachment to two parallel C-shaped rails (not in Fig. 5 shown),

Fig. 6

a cross section through the arrangement in Fig. 5 with the end of the underbody support attached to the two C-profile rails;

Fig. 7

an arrangement as in Fig. 3 wherein a plurality of devices are arranged in the underfloor receiving space,

Fig. 8

a part of a subfloor carrier to which are attached two plate-shaped elements which extend in the longitudinal direction of the car body in both directions away from the carrier and form a lower end of the subfloor receiving space,

Fig. 9

the arrangement according to Fig. 8 also in three-dimensional representation from a different angle, wherein the underbody support and the two plate-shaped elements are fully shown, and

Fig. 10

the arrangement according to Fig. 8 in three-dimensional representation, with the view is directed to the bottom of the arrangement.

Fig. 11

shows a cross section through a receiving space for receiving devices to be cooled and optionally other devices of a rail vehicle, wherein the receiving space is arranged below the bottom of the car body, not shown in the figure,

Fig. 12

a cross section similar to the one in Fig. 1 wherein an underbody support is shown, via which the weight of devices in the receiving space is discharged to the car body, and wherein above a device in the receiving space, but below the car body bottom cable channels are arranged,

Fig. 13

schematically a plan view of the interior of a receiving space, for. B. of in 11 and FIG. 12 shown receiving space, wherein a plurality of cooling devices, associated fans and the course of the air flow are shown.

Fig. 1 shows a single sub-floor support 1, which has a U-shaped profile, wherein the transverse leg 4 is designed to be significantly longer than the vertically extending longitudinal leg 2a, 2b. At the upper end of the first longitudinal leg 2a and also at the upper end of the second longitudinal leg 2b, both extending approximately vertically inwards, only slightly inclined inwardly from top to bottom, there is a respective T-shaped widening 5a, 5b, in a plate-shaped mounting surface opens, each having a plurality of through holes 6, of which only a few with these reference numerals in Fig. 1 are designated. In order to increase the stability of the carrier 1 in the region of the transition between the longitudinal limbs 2 and the transverse limb 4, a diagonal brace 3a, 3b which connects a central region of the longitudinal limb 2 with the transverse limb 4 diagonally is located in the transition region. The term longitudinal leg here does not refer to the longitudinal direction of the car body. In the upper region of the longitudinal limbs 2, an additional support 9a, 9b is optionally attached, in each case on the inside of the longitudinal limb 2, in order, for example, to provide an additional covering (not in FIG Fig. 1 shown) to attach carbody floor.

In the transition region between the longitudinal legs 2 and the transverse leg 4 is in each case a plurality of holes 10 a, 10 b, 10 c, 10 d and that at the in Fig. 1 left facing visible surface and on on the in Fig. 1 These two surfaces pointing to the left in front and to the right are realized in the aforementioned transition region by sheet-like, mutually parallel and spaced-apart material regions of the carrier 1. Therefore, it is also possible to hold in the space between the two material areas, for example, a screw head or tighten a nut. These holes 10 are used for fastening longitudinal struts, via which the carrier 1 is connected to longitudinally adjacent carriers.

The carrier 1 is made of aluminum, for example. It can be made from a plurality of individual parts. For example, the diagonal strut 3 is manufactured separately and only then connected to the longitudinal strut 2 and the cross member 4. The connection areas are in Fig. 1 not shown in detail. However, it is also possible in each case to produce the material regions which form the front left and right rear-facing surface of the carrier 1 in one piece and to connect them to each other by a sheet metal strip comprising the outside surfaces of the longitudinal limbs 2 and the downwardly facing surface of the transverse limb 4 forms. Furthermore, a further metal strip can be added later, which forms the inside surfaces of the longitudinal leg 2 and the diagonal struts 3 and the upward-facing surface of the transverse leg 4. The required joints are made for example by welding.

Four additional supports 7a, 7b, 7c, 7d with holes extending in the vertical direction are located on the surface of the transverse limb 4 pointing to the left front, wherein such support elements are also arranged on the side of the transverse limb 4 pointing to the right, or at least can be arranged if it is not the last carrier 1 in the longitudinal direction. These support elements 7 may be used for laying and connecting to plate-shaped elements or as attachment points for attaching devices in the receiving space.

The transverse leg 4 also has a plurality of through-holes 8 through which, for example, cables or lines for liquids or gases can be passed. In this way, for example, connection lines for underfloor devices can be passed through the carrier 1 and thus fixed in places in terms of their position.

Fig. 2 shows the carrier 1 from Fig. 1 with its transverse leg 4 and its longitudinal legs 2a, 2b, wherein the longitudinal legs 2 are fastened on the underside by a respective longitudinal member 24a, 24b of a rail vehicle car body. Of the car body are in addition to the longitudinal members 24, which preferably extend over almost the entire length of the car body (the longitudinal extent extends in a direction perpendicular to the plane of the figure Fig. 2 ), Also a bottom 13 and the lower portions of two side walls 11 a, 11 b shown. The bottom and the side walls 11 define a car body interior 17. The bottom 13 is composed in the embodiment of five plate-shaped elements 12 which are welded together. In this case, the hollow chamber structure of both the bottom 13 and the longitudinal member 24 can be seen. Preferably, it is extruded aluminum profiles. Not in Fig. 2 illustrated roof area and the side walls (in Fig. 2 with the exception of the lower sections) can also be made of extruded aluminum profiles of similar construction.

By a cuboid 15, which stands on the transverse leg 4 of the underbody support 1 is in Fig. 2 indicated that in the underfloor space between the bottom 13 and the transverse leg 4 underfloor devices (in particular to be cooled facilities) can be arranged.

Fig. 3 shows an arrangement with a total of eight longitudinally successively arranged underbody beams 101 - 108, for example, all as in Fig. 1 and in Fig. 2 are executed shown. The individual carriers 101 - 108 run as in FIG Fig. 1 shown transverse to the longitudinal direction and have a U-shaped profile when viewed in a plane perpendicular to the longitudinal direction.

Between the underbody beams 105 and 106 is located on the opposite sides in each case an additional strut 110a, 110b, which similar to the longitudinal struts 2 of Carrier 1 according to Fig. 1 and Fig. 2 can be configured. However, the additional struts 110 are not connected to the underbody beams 101-108 by a crossbar.

The underbody beams 101 - 108 are connected in pairs on both sides of the car body by a longitudinal strut 121-128 and 131-138 extending in the longitudinal direction of the car body. In the specific embodiment, not only a longitudinal strut is present on each side between the carrier 105 and the carrier 106, but a first longitudinal strut 125 or on the other side 135, which connects the carrier 105 with the additional struts 110, and both Pages a longitudinal strut 126, 136 which connects the additional strut 110 with the carrier 106. The connections of all the longitudinal struts 121-128 and 131-138 are each made in the transition region between the approximately vertically extending partial strut of the carrier and the extending approximately in the horizontal direction transverse strut of the carrier. To attach the longitudinal strut, for example, in Fig. 1 For example, threaded rods are introduced with external thread at the front end of a longitudinal strut in the holes 10 and secured on the opposite side of the bore by nuts.

In the Fig. 3 illustrated underbody construction with U-shaped underbody supports and longitudinal struts on the opposite sides represents an embodiment for a stable construction. However, such longitudinal struts extending in the longitudinal direction are not absolutely necessary. For example, the function of the longitudinal struts can be taken over by correspondingly stably configured plate-shaped elements, which are arranged between the pairs of mutually adjacent underbody beams and connected to the carriers.

Another possibility is the underbody construction in the way in Fig. 3 shown running with U-shaped underbody supports and longitudinally extending side members and additionally plate-shaped elements to install as a panel. Such an embodiment is in Fig. 4 shown. Same reference numerals in FIG Fig. 4 as in Fig. 3 denote the same elements. On the underside of the U-shaped underbody beams 101-108 are mounted plate-shaped fairings 144a-144h which form the bottom of the underbody space. It is also possible, as shown in the plate-shaped element 144f, that the plate-shaped panels have a cutout 139, so that the underbody space is accessible from below through the cutout 139 or so that an underfloor device for which the height of the underfloor Space is not sufficient or that it should not be located in a closed room, protrudes. In particular, for the purpose of cooling the underfloor device such a cutout 139 may be useful. The driving wind then cools the bottom of the device. Also, as indicated in the plate-shaped panels 144g, an air-permeable mesh in the panel may be present, so that an air exchange is possible.

Furthermore, the side surfaces of the in Fig. 4 be shown disguised support structure with plate-shaped elements 141. In this way, with the exception of the section 139 closed on three sides U-shaped trough is formed, which bounds the underbody space. The plate-shaped elements on the side surfaces preferably each have a flap 140 (as shown at element 141 c, 141 d, 141 e) and / or an air inlet opening with a dirt separator (eg ventilation grille and / or filter).

At the in Fig. 4 to the left front end facing the construction, two damping elements may be present (not shown), which are connected to the transition region of the carrier 108 between the transverse leg and its approximately vertically extending longitudinal leg. These damping elements allow a support against a not in Fig. 4 illustrated additional support means, wherein the damping elements deform elastically under load and thus in particular allow a deformation of the support structure relative to the additional support.

As indicated to the right of the side trim panel 141 at one location, the side trim panel 141 may include at least one reclosable opening, such as a flap 140 or door or removable trim panel, so that the space within the underbody construction is accessible.

Fig. 5 shows a three-dimensional representation of one of the upper ends of an underbody support, for example, the carrier 1 according to Fig. 1 , Same reference numerals as in Fig. 1 denote equal parts. The surface formed by a plate-shaped region at the upper end of the carrier has in particular the in Fig. 1 shown a total of eight holes 6, which in Fig. 5 are not recognizable, because through the holes 6 each extending a screw 85 which is secured in its lower end by a nut 87 against loosening and falling out. The screws 85 each hold in pairs a groove body 71, the one in the longitudinal direction (from the right rear to the left front in Fig. 5 ) has a constant cross-sectional profile and in the embodiment has a U-shaped profile.

As Fig. 6 5, these groove bodies 71 can be arranged in C-shaped grooves 83, 84, the opening of the grooves 83, 84 allowing the shafts of the screws 85 to pass downwards. It is located between the plate-shaped upper end of the longitudinal strut 2a and the nut 87 each have a spacer 81 a, 81 b, which facilitates the assembly and leads to a uniform pressing of the parts to be screwed together when the nuts 87 are tightened. A rotation of the heads of the screws 85 is prevented by the groove body 71.

The C-profile-shaped, mutually parallel grooves 83, 84 are preferably on the underside of one of the longitudinal members 24 (in the example of Fig. 6 Side member 24a) arranged. The corresponding area in the specific embodiment of Fig. 2 is located below the longitudinal member 24a and is marked by an arrow with the reference numeral 83 to indicate that, inter alia, the groove 83 is located in the region. The grooves 83, 84 and corresponding grooves on the other side of the car body on the other side member need not extend over the entire length of the side member. Rather, the grooves extend, for example, over a longitudinal section over which the longitudinal position of the underbody support is to be freely adjusted.

In the Fig. 7 shown devices are arranged in the receiving space, which, for example, by the basis of Fig. 3 and Fig. 4 explained underbody construction is limited. Same reference numerals in FIG Fig. 7 like in the Fig. 3 and 4 denote equal parts. For example, the devices are various liquid containers 201, 202, an electrical distribution device 204 to be cooled, a ventilation device 205 to be cooled, gas containers 206, a transformer 207 to be cooled, and converters 208 to be cooled as well as a cooling device 209. Preferably all these devices are placed on a plate-shaped element and / or a support of the underbody construction, so that they exert their entire weight or at least almost the entire weight on the U-shaped underbody support 101 - 108.

In the Fig. 8 shown partial view of an underbody support 1 and two plate-shaped elements 91 a, 91 b illustrates that can be dispensed with longitudinal struts connecting adjacent underbody support. Again, like reference numerals designate the same parts as in other figures. The carrier 1 is therefore, for example, the in Fig. 1 and Fig. 2 shown carrier. However, in other embodiments of U-shaped underbody supports plate-shaped elements of screwed down or otherwise secured from below, as indicated by Fig. 8 - 10 is described.

The plate-shaped elements 91 a, 91 b are provided at their ends which are arranged at a small distance from one another in the region of the support 1, each with a vertical cross-section Y-shaped profile which surrounds the end of the plate-shaped support 91 and a from the end-extending plate-shaped part, the through holes for passing screws 93 (see Fig. 10 ) having. The underside of the carrier 1 is provided with corresponding holes with internal thread into which the screws 93 are screwed. In the reverse of Fig. 10 showing the bottom of the assembly, the heads of the screws 93 can be seen, including a spacer 98 and again below the projecting plate-shaped element of the profile 94, which covers the underside of the carrier 1. This way not only, as in Fig. 9 shown, two plates 91 are secured to the underside of the carrier 1, but in the same way, for example, another four plates, two of which are fastened symmetrically to the median plane of the carrier on the other longitudinal strut 2a and two further plates fill the space between the peripheral plates ,

In FIG. 11 schematically the air flow from the environment of the rail vehicle through an air inlet opening 307, a fan 309, a device to be cooled 315 and again out of the receiving space 301 through an air outlet opening 311 shown in the environment. The presentation is simplified. Other components may be provided, in particular dirt particle filters at the air inlet opening 307 and barriers for dirt at the air outlet opening 311 to prevent the occurrence of dirt at occasionally reversed air pressure ratios. Also, the air inlet does not have to take place at the same position in the longitudinal direction of the rail vehicle on which the fan is located. The same applies to the position of the air outlet opening in the longitudinal direction of the rail vehicle. The longitudinal direction of the rail vehicle extends in 11 and FIG. 12 perpendicular to the figure plane. The reason why the air inlet opening and the fan do not have to be at the same position or not in the same longitudinal section is that the accommodating space 301 contains a continuous main air volume. In particular, the air can therefore perpendicular to the plane of the figure FIGS. 11 and 12 in particular flow between the device to be cooled 315 and the side walls 317a, 317b in the areas from which derive the fan or the air and supply the devices to be cooled.

Fig. 12 shows that this air flow is also possible at longitudinal positions in which an underbody carrier 300 is located, the z. B. the in Fig. 1 shown underbody support 1 can be. Further shows Fig. 12 in that cable ducts 320, 321 can be located below the vehicle body floor 313 but above a device 315 to be cooled, in which cables running in particular in the longitudinal direction of the rail vehicle can be laid, which in Fig. 12 designated by the reference numeral 323.

Fig. 13 12 schematically shows the arrangement of devices within a subfloor receiving space 401. This may in particular be the receiving space between the two bogies of a powered rail vehicle (eg a high speed power train), the traction motors in the bogies and traction motors the bogies themselves are not in Fig. 13 are shown. However, air supply ducts 405a, 405b outgoing from inside the receiving space 401 driving motor fans 403a, 403b lead from the receiving space 401 to the traction motors of one of the adjacent bogies. The air taken in by the traction motor fans 403 from the main air ducts of the accommodating space 401 flows through these air supply passages 405 to the traction motors.

Preferably in the middle (with respect to the direction transverse to the direction of travel of the rail vehicle, the direction of travel runs in Fig. 13 from top to bottom) several devices and units to be cooled are arranged. In this case, three units 411, 412, 413 are combined to form a common device to be cooled, ie the units 411, 412, 413 are assigned a common fan 410. In the particular embodiment, the fan 410 is bisected (as indicated by a diagonal hyphen) and conveys cooling air in the lower right portion to the unit 411 and in the lower left part to the units 412, 413 serially from the unit Cooling air to be flowed through. The units 411, 412, 413 may in particular be different power converters, in particular a traction converter 411, a supply-side rectifier 412 and an auxiliary inverter 413.

Furthermore, in Fig. 13 another device 417 to be cooled is shown, to which a further fan 415 is assigned. The fan 415 sucks air from the main air volume of the receiving space 401 and delivers it to the device to be cooled 417, in which it is z. B. may be a battery charger, which is not in Fig. 13 illustrated battery of electrical and / or electrochemical energy storage for storing electrical energy is charging.

The air flows generated by the fans 410, 415 and optionally other fans lead past the devices to be cooled and / or through the devices to be cooled and preferably pass through in each case by an air outlet opening 419, 420, 421 in the bottom of the receiving space 401 in the environment, the air outlet openings 419, 420, 421 in Fig. 13 are shown by a dashed frame.

Using the arrows that represent the airflow is in Fig. 13 clearly seen that the air entering through the air inlet openings 424 to 427 in the receiving space 401, in the longitudinal direction of the receiving space (from top to bottom in Fig. 13 ) can distribute.

In the in Fig. 13 shown embodiment are located in the front part of the receiving space (bottom in the figure) no air inlet openings, since there may arise due to high speeds sub-pressures outside of the receiving space 401. Due to the large, continuous main air volume but also the air flows to the traction motor fans 403 and the fan 410 are ensured without being significantly slowed down.

Claims (12)

1. A rail vehicle, particularly train part of a high-speed train, wherein

   - the rail vehicle comprises a railcar body (11, 13) with a floor (13), which defines the bottom of a railcar body's interior (17) for the transport of passengers and/or freight,

   - below the floor (13) there is a receiving space (301; 401) formed for accommodating vehicle equipment (15; 201, 202, 204, 205, 206, 207, 208; 411, 412, 413, 417) to be cooled, wherein the receiving space (301 ; 401) is bounded on all sides, exhibits at least one air inlet aperture (307; 424, 425, 426, 427) and at least one air outlet aperture (139; 311; 419, 420, 421) and is protected against the ingress of dirt,

   - the at least one air inlet aperture (307; 424, 425, 426, 427) opens a main air volume of the receiving space (301; 401), wherein the main air volume contains the major part of the air in the receiving space (301; 401) and thus forms a reservoir for cooling air,

   - at least one device (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled is arranged in the receiving space (301; 401) and at least one fan (309; 410, 415) is arranged , which during operation accelerates air from the main air volume with the result that air flows to the at least one device to be cooled,

   wherein in the receiving space (401) a plurality of vehicle devices (410, 411, 412, 413, 415, 417) to be cooled is arranged and distributed in the longitudinal direction of the rail vehicle over a longitudinal section of the receiving space (401),
   characterized in that
   the main air volume extends at least over the longitudinal section and the main air volume is continuous in the longitudinal section, i.e. not divided into individual compartments that are separate from one another and sealed off from one another, and
   in a first area of the said longitudinal section that is situated closer to the front end of the rail vehicle oriented in the direction of travel, where at least one (410, 411) of the vehicle's devices (410, 411, 412, 413, 415, 417) to be cooled is located, in side walls of the receiving space (401) there is no air inlet aperture present, however in a second area of the longitudinal section, which compared to the first area of the longitudinal section is farther from the front end of the rail vehicle oriented in the direction of travel, there are air inlet apertures (424 - 427) arranged in the side walls of the receiving space (401), which open the main air volume of the receiving space (301; 401) to the surroundings of the rail vehicle through which air can enter into the main air volume of the receiving space (401).
2. A rail vehicle according to claim 1, wherein the receiving space extends over the maximum length available in the underfloor area in the direction of travel of the rail vehicles between two bogies of the rail vehicle.
3. A rail vehicle according to claim 1 or 2, wherein for each of the plurality of devices (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled at least one fan (309; 410, 415) is associated, which during operation accelerates air from the main air volume with the result that air flows to the associated devices (315; 411, 412, 413, 417) to be cooled and cools it.
4. A rail vehicle according to one of the preceding claims, wherein the majority of the weight forces of at least one of the devices (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled is applied downward on a substructure (1; 300) of the receiving space (301; 401) and acts on the railcar body (11, 13) via the substructure (1; 300) such that above the device (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled there is a free space at the bottom of (13) of the railcar body's interior (17).
5. A rail vehicle according to one of the preceding claims, wherein in each case a longitudinal support (24) is present in a transition area between the floor (13) and the side walls (11) of the railcar body's interior (17) for transmitting longitudinal forces, and the said support extends in the longitudinal direction of the railcar body (11, 13), wherein the railcar body (11, 13) exhibits at least one subfloor support (1; 300), which extends under the floor (13) from the one longitudinal support (24a) to the other longitudinal support (24b), wherein the subfloor support (1; 300) extends in part with a clearance to the floor (13) such that part of the receiving space (301; 401) is present between the subfloor support (1 ; 300) and the floor (13).
6. A rail vehicle according to one of the preceding claims, wherein the devices (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled are arranged within the receiving space with a clearance to at least one side wall of the receiving space (301; 401) with the result that between the device and the side wall a free space remains which forms a part of the main air volume.
7. A method to manufacture a rail vehicle, particularly a train part of a high-speed train, wherein

   - for the rail vehicle a railcar body (11, 13) is provided that comprises a floor (13), which defines the bottom of a railcar body's interior (17) for the transport of passengers and/or freight,

   - below the floor (13) a receiving space (301; 401) is formed for accommodating vehicle equipment (15; 201, 202, 204, 205, 206, 207, 208; 411, 412, 413, 417) to be cooled, wherein the receiving space (301 ; 401) is bounded on all sides, wherein at least one air inlet aperture (307; 424, 425, 426, 427) and at least one air outlet aperture (139; 311; 419, 420, 421) of the receiving space (301; 401) are provided and the said receiving space (301; 401) is protected against the ingress of dirt,

   - the at least one air inlet aperture (307; 424, 425, 426, 427) is provided in such a way that a main air volume of the receiving space (301; 401) is opened, wherein the main air volume contains the major part of the air in the receiving space (301; 401) and thus forms a reservoir for cooling air,

   - at least one device (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled is arranged in the receiving space (301; 401) and at least one fan (309; 410, 415) is arranged , which during operation accelerates air from the main air volume with the result that air flows to the at least one device (15; 204,205, 207, 208; 411, 412, 413, 417) to be cooled,

   wherein in the receiving space (401) a plurality of vehicle devices (410, 411, 412, 413, 415, 417) to be cooled is arranged and distributed in the longitudinal direction of the rail vehicle over a longitudinal section of the receiving space (401),
   characterized in that
   the main air volume extends at least over the longitudinal section and the main air volume is continuous in the longitudinal section, i.e. not divided into individual compartments that are separate from one another and sealed off from one another, and
   in a first area of the said longitudinal section that is situated closer to the front end of the rail vehicle oriented in the direction of travel, where at least one (410, 411) of the vehicle's devices (410, 411, 412, 413, 415, 417) to be cooled is located, in side walls of the receiving space (401) there is no air inlet aperture provided, however in a second area of the longitudinal section, which compared to the first area of the longitudinal section is farther from the front end of the rail vehicle oriented in the direction of travel, there are air inlet apertures (424 - 427) arranged in the side walls of the receiving space (401), which open the main air volume
   of the receiving space (301; 401) to the surroundings of the rail vehicle and through which air can enter into the main air volume of the receiving space (401).
8. A method according to the preceding claim, wherein the at least one air inlet aperture (307; 424, 425, 426, 427) or at least one of the air inlet apertures (307; 424, 425, 426, 427) is formed as recess in a side wall of the receiving space (301; 401).
9. A method according to claim 7 or 8, wherein for each of the plurality of devices (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled at least one fan (309; 410, 415) is associated, which during operation accelerates air from the main air volume with the result that air flows to the associated device (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled and cools it.
10. A method according to one of the claims 7 to 9, wherein the majority of the weight forces of at least one of the devices (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled is applied downward on a substructure (1; 300) of the receiving space (301; 401) and acts on the railcar body (11, 13) via the substructure (1; 300) such that above the device (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled there is a free space at the bottom of (13) of the railcar body's interior (17).
11. A method according to one of the claims 7 to 10, wherein in each case a longitudinal support (24) is arranged in a transition area between the floor (13) and the side walls (11) of the railcar body's interior (17) for transmitting longitudinal forces such that it extends in the longitudinal direction of the railcar body (11,13), wherein at least one subfloor support (1; 300) is provided, which extends under the floor (13) from the one longitudinal support (24a) to the other longitudinal support (24b), wherein the subfloor support (1; 300) extends in part with a clearance to the floor (13) such that part of the receiving space (301; 401) is present between the subfloor support (1 ; 300) and the floor (13).
12. A method according to one of the claims 7 to 11, wherein one of the devices (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled is arranged within the receiving space with a clearance to at least one side wall of the receiving space (301; 401) with the result that between the device to be cooled and the side wall a free space remains which forms a part of the main air volume.

Images