Device for dissipating waste heat and ion accelerator arrangement with such a device

Abstract

Device for dissipating waste heat from a heat source via a heat conduction arrangement to a heat sink, wherein the device is used in a spacecraft and the heat sink is the surrounding free space into which a radiant arrangement connected to the heat conduction arrangement emits thermal radiation, and wherein the heat conduction arrangement is thermally connected to a support structure which is arranged between the heat source and the heat conduction arrangement, and wherein the support structure and the heat conduction arrangement are made of different materials, characterized in that the heat conduction arrangement consists at least predominantly of an Al-Si alloy with a hypereutectic Si component.

Description

[0001] The invention relates to a device for dissipating waste heat and an ion accelerator arrangement with such a device.

[0002] Ion accelerators are known as electric propulsion systems for satellites or other spacecraft. An advantageous ion accelerator propulsion system of this type is described, for example, in WO 2003 / 000550 A1. The known ion accelerator contains a multi-stage magnet arrangement with permanent magnet rings and pole shoe rings, which surround a chamber wall of an ionization chamber.

[0003] During the operation of such ion accelerator arrangements, waste heat is generated at the chamber wall that laterally delimits the ionization chamber. This heat must be dissipated to the outside. Due to volume and weight limitations in use in spacecraft and the use of high voltages in such ion accelerator arrangements, there are special requirements for devices for dissipating this waste heat. Particularly in spacecraft applications, this heat can only be released by radiation into free space, acting as a heat sink. For this purpose, at least some of the heat is dissipated from the chamber wall via the magnet arrangement. The temperature resistance of the magnet arrangement is limited, especially when permanent magnets are used.

[0004] In traveling-wave tubes, heat loss occurs primarily through the impact of electrons from a focused electron beam on the anode, which acts as a collector. The anode is typically made of copper. The heat loss is dissipated via a radiator array that is thermally coupled to the anode, either directly or via an intermediate structure.

[0005] In a device for dissipating waste heat, particularly in electrical devices such as ion accelerator arrangements or traveling wave tube arrangements, a heat dissipation arrangement facing away from the waste heat source should be mechanically fixed and thermally conductive with a support structure, such as a magnet arrangement facing the chamber wall in the ion accelerator arrangement or the collector in the traveling wave tube arrangement, wherein the material, geometry and structure of the magnet arrangement or the collector are generally largely determined by the function of the respective electrical device.

[0006] It is known to provide copper bodies in the heat dissipation arrangement which conduct heat outwards to a radiant arrangement which emits heat via outwards facing surfaces, and which are coupled to the support structure with special transition structures to compensate for mechanical stresses occurring during temperature fluctuations or are soldered onto metallic surfaces of the support structure.

[0007] US Patent 4,703,339 A describes a device for dissipating waste heat from a heat source to a heat sink via a heat conduction arrangement. US Patent 5,990,600 A and German Patent DE 41 09 664 A1 describe heat dissipation in traveling wave tubes.

[0008] The present invention is based on the objective of providing an improved device for the removal of waste heat, as well as an ion accelerator arrangement with such a device.

[0009] Solutions according to the invention are described in the independent patent claims. The dependent claims contain advantageous embodiments and further developments of the invention.

[0010] In a device for dissipating waste heat from a heat source, particularly in one of the aforementioned electrical devices, via a heat conduction arrangement which is thermally connected to a support structure facing the heat source, to a heat sink, the use of an aluminum-silicon alloy in the heat conduction arrangement proves surprisingly advantageous. The heat conduction arrangement advantageously consists predominantly, preferably entirely, of the Al-Si alloy. It is used in a spacecraft such that the heat sink is the surrounding free space and a radiant array connected to the heat conduction arrangement emits thermal radiation into the space.

[0011] According to the invention, an Al-Si alloy with a hypereutectic silicon content is used. The coefficient of thermal expansion of the Al-Si alloy advantageously deviates by less than 30%, particularly less than 20%, and preferably less than 10%, from the coefficient of thermal expansion of the support structure. This advantageously utilizes the fact that the coefficient of thermal expansion of a hypereutectic Al-Si alloy can be adjusted over a wide range by varying the proportions of Al and Si in the alloy, and is thus readily adaptable to a coefficient of thermal expansion determined by the material of the support structure.

[0012] The heat conductor arrangement is advantageously designed in a form surrounding the support structure. The support structure advantageously surrounds a space containing the heat loss source laterally along a longitudinal axis. The heat conductor arrangement is advantageously subjected to elastic tension against the support structure, resulting in continuous and large-area heat transfer at the interface between the support structure and the heat conductor arrangement. This elastic tension can be achieved, in particular, by heat shrinking the heat conductor arrangement onto the support structure. The heat conductor arrangement can also advantageously form a mechanical connection between several parts of the support structure.

[0013] For good heat transfer between the support structure and the heat conductor, it is also advantageous to provide a thinner layer, typically less than 1 mm, and in particular less than 0.1 mm, at the interface between the support structure and the heat conductor. This layer should be made of a material with higher ductility than the materials of the support structure and the heat conductor. The use of gold for such an intermediate layer is particularly advantageous. The support structure and the heat conductor can also be soldered together.

[0014] The support arrangement advantageously includes a magnet arrangement, in particular a magnet arrangement with permanent magnet bodies. The material of such a permanent magnet arrangement is preferably a rare-earth alloy, in particular samarium-cobalt (SmCo). The permanent magnet arrangement advantageously includes at least one, preferably several, ring magnet bodies with axially directed magnetization with respect to the ring axis.

[0015] In another advantageous embodiment, instead of an AISi alloy, the heat conduction arrangement can also consist at least predominantly of beryllium, which also has an advantageous coefficient of thermal expansion and a low specific weight, but is more expensive and more difficult to handle.

[0016] The production of a permanent magnet assembly with several axially sequentially arranged ring magnet bodies is particularly advantageous, regardless of the material of the heat-conducting arrangement, through thermal shrinking of the heat-conducting arrangement. This method achieves a simple and advantageous bond between the multiple ring magnet bodies and / or, in particular, stabilizes and protects fragile magnet bodies, such as those made of SmCo, through the uniform pressure load on all sides. If no heat loss needs to be dissipated, the thermal conductivity of the heat-conducting arrangement, which then primarily functions as a mechanical shell, is of secondary importance.

[0017] Such a device for dissipating waste heat is particularly advantageous in waste heat-generating electrical systems in spacecraft, where, due to the lack of repair options, consistently good heat transfer is of paramount importance, and where the large temperature differences between standstill and operation of the electrical units place particular stress on material connections. In the especially advantageous use of a heat conduction arrangement made of an Al-Si alloy in a spacecraft, the heat conduction arrangement advantageously transfers the heat absorbed via the support structure to a radiating array, which then emits the heat as thermal radiation into the surrounding space, acting as a heat sink.

[0018] In an ion accelerator arrangement with a magnet arrangement, it is surprisingly evident that an aluminum-silicon alloy with a hypereutectic silicon content, used as the material for at least the predominant part of the heat conduction arrangement, is particularly advantageously suited to the typical magnetizable materials of the magnet arrangement, as determined by the function of the ion accelerator arrangement. The silicon content of the hypereutectic Al-Si alloy is preferably at least 40%. Advantageously, the silicon content of the alloy is a maximum of 60%. In a eutectic Al-Si alloy, the silicon content is approximately 12%.

[0019] The hypereutectic Al-Si alloy advantageously possesses a higher thermal conductivity and a lower specific gravity compared to the materials of the magnet assembly. Due to its material properties, it can be mechanically coupled to the surfaces of typical materials in the magnet assembly of the ion accelerator assembly, exhibiting particularly favorable heat transfer. In particular, the hypereutectic Al-Si alloy has a coefficient of thermal expansion that closely approximates that of the magnetizable materials preferably used in typical magnet assemblies, especially iron as a soft magnetic material or rare-earth materials, preferably SmCo, as permanent magnetic materials. A small deviation in the coefficients of thermal expansion is of significant advantage, as high temperature fluctuations can occur in an ion accelerator assembly of the aforementioned type.

[0020] Magnetizable materials of typical support structures, especially Fe and SmCo, advantageously possess a coefficient of thermal expansion between 8×10 -6 / K and 16×10 -6 / K, especially between 11×10 -6 / K and 13×10 -6 / K. The coefficient of thermal expansion of the hypereutectic Al-Si alloy provided in the heat conduction arrangement according to the invention can advantageously be further varied by the percentage ratio of Al and Si and adapted to the materials of the magnet arrangement. The coefficient of thermal expansion of the hypereutectic Al-Si alloy advantageously deviates by less than 30%, in particular less than 20%, preferably less than 10%, from the respective coefficients of expansion of the materials of the magnet arrangement.

[0021] In an advantageous embodiment, the heat conduction arrangement surrounds the magnet arrangement radially with respect to a central axis of the ion accelerator arrangement and is preferably shrunk onto the magnet arrangement or parts thereof under elastic prestressing of the materials, so that the heat conduction arrangement and the magnet arrangement bear against each other with good surface contact under elastic prestress. At the interfaces, intermediate layers of a material with good thermal conductivity and that is softer than the materials of the magnet arrangement and the heat conduction arrangement, for example gold, can advantageously be provided, resulting in particularly good heat transfer due to a particularly large contact area caused by deformation of the intermediate layer.

[0022] The heat conduction arrangement advantageously dissipates heat as thermal radiation into the environment from surface areas of a radiator arrangement coupled to the heat conduction arrangement that face away from the magnet arrangement, and, preferably, into the surrounding empty space when the ion accelerator arrangement is used in a spacecraft. The surfaces radiating the thermal radiation into the environment can be made of a material other than the hypereutectic Al-Si alloy and can, in particular, be formed by coatings.

[0023] The heat conduction arrangement advantageously consists at least predominantly (>50%), preferably essentially entirely, e.g., with the exception of a surface coating, of the hypereutectic Al-Si alloy. Preferably, the radiator arrangement also consists predominantly or essentially entirely of the hypereutectic AlSi alloy.

[0024] The ion accelerator arrangement comprises an ionization chamber, wherein a heat loss source is arranged on or near a chamber wall, typically dielectric, e.g., ceramic, which delimits the chamber. In the ionization chamber, a working gas is ionized, and the ions are preferably electrostatically accelerated in a longitudinal direction within the ionization chamber and ejected through a single opening in the chamber.

[0025] The magnet arrangement comprises several permanent magnet rings surrounding the ionization chamber of the ion accelerator arrangement, spaced apart from one another in a longitudinal direction of the chamber. In a preferred embodiment, longitudinally adjacent permanent magnet rings have opposite pole orientations in the longitudinal direction, so that longitudinally aligned poles of adjacent magnet rings face each other. This creates a cusp structure of the magnetic field in the longitudinal direction between adjacent magnet rings in the chamber, as described, for example, in an ion accelerator from WO 2003 / 000550 A1 mentioned above. A multi-stage magnet arrangement with at least two such longitudinally spaced cusp structures of the magnetic field in the ionization chamber of an electrostatic ion accelerator is particularly advantageous.The material of the permanent magnet rings is preferably a rare-earth alloy, in particular with samarium and cobalt as its main components. Samarium-cobalt permanent magnets are known and commonly used and are characterized by a higher Curie temperature compared to neodymium magnets.

[0026] Advantageously, pole shoe rings made of soft magnetic material, in particular iron, are arranged between longitudinally spaced permanent magnet rings.

[0027] The resulting heat loss is particularly problematic for permanent magnet materials, for which high temperatures are not permissible, and which, on the other hand, generally have low thermal conductivity and can therefore only make a small contribution to dissipating heat loss to the heat conduction arrangement.

[0028] The permanent magnet bodies of the magnet assembly typically do not lie directly against the outer surface of the chamber wall that laterally delimits the chamber, but are spaced from it by a narrow gap, so that heat loss from the chamber wall to the permanent magnet bodies occurs via thermal radiation. A thermal radiation reflector device between the chamber wall and the permanent magnet bodies reduces this heat transfer and prevents overheating of the permanent magnet material. Such a thermal radiation reflector device can include mirror elements arranged radially between the outer chamber wall and the permanent magnet bodies. Preferably, the thermal radiation reflector device is formed by a reflective coating on the surfaces of the permanent magnet bodies facing the chamber wall, with gold being advantageously used as the coating material.Advantageously, no heat radiation reflector is provided radially between the outer chamber wall and the surfaces of the soft magnetic pole shoes that face it, so that waste heat is dissipated to the outside to the heat conduction arrangement via the pole shoes, which are preferably made of iron and are not temperature-sensitive, yet also highly thermally conductive. The reduction of heat absorption by the permanent magnet bodies by means of the heat radiation reflector is also advantageous for overheat protection of the permanent magnet bodies and for the distribution of the resulting waste heat, regardless of the material of the heat conduction arrangement.

[0029] In a traveling-wave tube arrangement, the use of an Al-Si alloy, particularly one with a hypereutectic Si content, also proves to be particularly advantageous. Here, a heat conduction arrangement is advantageously connected indirectly or preferably directly to the anode body (collector), which typically consists of copper, as a support structure. This connection is particularly advantageous if the heat conduction arrangement is shrink-fitted to ensure a permanently good thermally conductive surface contact. In such a case, the Si content of the Al-Si alloy can typically be chosen to be lower than in the preceding example of the ion accelerator, since the coefficient of thermal expansion of the anode body is generally higher than that of the magnet assembly of the ion accelerator arrangement. The heat conduction arrangement can be soldered to the anode body.

[0030] The invention is further illustrated below with reference to preferred embodiments and the figures. These show: Fig. 1. A schematic diagram of an ion accelerator, Fig. 2 a section of a traveling wave tube arrangement.

[0031] Fig. Figure 1 schematically shows a section through an ion accelerator arrangement, which, without loss of generality, is assumed to be rotationally symmetric about a longitudinal axis LA. Due to the symmetry, only one half of the section is shown above the longitudinal axis LA. The longitudinal axis LA runs parallel to a longitudinal direction LR, which is shown along with the radius coordinate R. An ionization chamber IK is bounded radially by a chamber wall KW made of dielectric, in particular ceramic, material. The chamber cross-section is assumed to be constant in the longitudinal direction LR. The ionization chamber is open longitudinally to one side, to the right in the sketch, allowing an accelerated plasma jet PB to exit there. This jet provides the thrust in an ion accelerator arrangement used as a spacecraft propulsion system.An anode assembly AN is arranged at the base of the ionization chamber IK, opposite the beam exit aperture AO in the longitudinal direction. A cathode assembly KA is arranged in the region of the beam exit aperture AO, preferably laterally offset from it. During operation of the arrangement, a high voltage is applied between the cathode assembly KA and the anode assembly AN, which generates an electric field in the ionization chamber pointing in the longitudinal direction LR. This field accelerates electrons towards the anode assembly and accelerates positive ions generated by the ionization of the working gas towards the beam exit aperture AO.

[0032] Outside and surrounding the plasma chamber is a magnetic arrangement comprising permanent magnet bodies MR, in particular made of SmCo, arranged longitudinally alongside and between these pole shoe bodies PR. The permanent magnet bodies MR and the pole shoe bodies PR are preferably each annular with respect to the longitudinal axis LA. However, several individual bodies can also be grouped around the axis. The poles of the magnetic bodies are aligned longitudinally, and longitudinally adjacent magnetic bodies have opposite polarities to each other, so that like poles are not in contact with each other. Fig. Two south poles S are positioned opposite each other at a distance. This type of arrangement of permanent magnet bodies creates a magnetic field MF in the ionization chamber IK, which forms so-called cusp structures in the region of the poles of the magnet bodies. These are areas in which the field lines curve from the longitudinal axis LA towards the chamber wall KW, transitioning into an approximately radial magnetic field pattern. The pole shoe bodies PR can advantageously shape this field pattern into a form that is further improved for the function of the ion accelerator arrangement.

[0033] The structure and function of such an ion accelerator arrangement are known in themselves, for example from the prior art mentioned at the beginning.

[0034] In such an ion accelerator arrangement, the thermal load on the chamber wall is already reduced compared to known Hall ion accelerators. However, there is still a heat loss to the area of ​​the chamber wall facing the ionization chamber due to electrons and ions striking it and radiation from the plasma forming in the ionization chamber. The heat loss to the chamber wall is somewhat higher in the longitudinal region of the pole shoe bodies (PR) compared to the longitudinal regions encompassing the magnet bodies (MR). The heating of the chamber wall also causes heat to be radiated from the radially outward-facing side of the chamber wall towards the magnet array. This heat is then transported radially outwards via the magnet array and radiated into the surrounding space, for which a radiation array advantageously possesses large-area radiation structures (SS).

[0035] In the advantageous example outlined, a heat dissipation device comprises a radially external emitter arrangement with a sheath SM and the aforementioned emitter structures SS on the one hand, and a heat conduction arrangement located between the emitter arrangement and the magnet arrangement on the other. At least the heat conduction arrangement consists at least predominantly of the hypereutectic AlSi alloy. The heat conduction arrangement includes several ring bodies LM, LP as heat conductors, wherein the ring bodies LP are arranged in the longitudinal region of the pole shoe bodies PR and the heat conductors LM in the region of the permanent magnet bodies MR, and are each mechanically and thermally coupled to the pole shoe bodies PR and the permanent magnet bodies MR, respectively. These heat conductors and / or the emitter arrangement SM, SS advantageously consist at least predominantly of a hypereutectic AlSi alloy with a silicon content of advantageously at least 40%.The proportion of silicon in the hypereutectic Al-Si alloy is advantageously no more than 60%. Further additions in small proportions are possible in principle.

[0036] The hypereutectic Al-Si alloy used for the thermal interface materials allows for a coefficient of thermal expansion very close to that of iron or SmCo. The thermal interface materials LP and LM are preferably designed as closed ring bodies. They are preferably radially clamped to the outward-facing surfaces of the pole shoe bodies PR or permanent magnet bodies MR to ensure a permanently mechanically stable surface contact and good heat transfer in the radial direction. Advantageously, intermediate layers of a highly thermally conductive material, which is softer than the opposing materials of the thermal interface materials and the pole shoe bodies or permanent magnet bodies, can be inserted at the interfaces between the thermal interface materials LP and the pole shoe bodies PR, and between the thermal interface materials LM and the permanent magnet bodies MR.Such an intermediate layer, due to its increased contact area, results in further improved radial heat transfer to the outside. The use of gold for such intermediate layers is particularly advantageous. Such an intermediate layer can also be provided between the radiator assembly with the radiator sheath SM and the heat conduction assembly with the heat conductors LP, LM.

[0037] Advantageously, the magnet assembly with the heat dissipation device is constructed by connecting the pole shoe bodies PR to the heat conductors LP and the permanent magnet bodies MR to the heat conductors LM. The resulting ring-shaped assemblies are then axially aligned and rigidly connected. Advantageously, the outer surface of the heat conductor assembly formed by the heat conductors LP and LM is then smoothed and brought to a defined outer dimension. Advantageously, the radiator assembly is then heated to a temperature higher than that of the heat conductor assembly, causing it to expand, and slid longitudinally over the heat conductor assembly. As the radiator assembly cools and shrinks, it presses radially against the outer surface of the heat conductor assembly, thus re-establishing good thermal contact.

[0038] The surfaces of the permanent magnet bodies MR that radially face the chamber wall KW are provided with a coating RE as a reflector, which reduces the absorption capacity for thermal radiation and thus the heat transfer from the chamber wall to the permanent magnet bodies. The coating advantageously consists of gold. The coating does not extend to the surfaces of the pole shoe bodies facing the chamber wall, and is therefore interrupted in the longitudinal direction at the pole shoe bodies.

[0039] During operation of the ion accelerator arrangement, the chamber wall is heated and radiates heat radially outwards towards the magnet arrangement. The heat absorbed by the magnet arrangement is transported according to a radial temperature gradient via the permanent magnet bodies MR, the pole shoe bodies PR, and the heat conduction arrangement with heat conductors LP, LM to the shell SM of the radiation arrangement, and there, in particular via the radiation structures SS, it is emitted as thermal radiation into space.

[0040] Due to the relatively low thermal conductivity of the permanent magnet bodies MR, for example made of SmCo, radial heat transfer occurs primarily via the pole shoe bodies PR, which are preferably made of iron, despite their smaller longitudinal expansion. The distribution of the contributions to radial heat conduction within the magnet assembly corresponds favorably to the higher wall temperature in the longitudinal regions of the pole shoe bodies, resulting from the greater heat input at these longitudinal positions. The thermal radiation reflector arrangement is advantageously interrupted in the longitudinal regions of the pole shoe bodies and is present only in these longitudinal regions. Good heat transfer from the chamber wall to the pole shoe bodies, which are preferably made of iron, is beneficial for radial heat dissipation.

[0041] Due to the reflector arrangement on the surfaces of the permanent magnet bodies facing the chamber wall, the temperature of the chamber wall can be higher in the longitudinal regions of the permanent magnet bodies than in the longitudinal regions of the pole shoe bodies. To a limited extent, heat equalization in the longitudinal direction can occur through thermal conduction within the chamber wall material. However, the higher chamber wall temperature also leads to increased heat radiation into the ionization chamber, which partially compensates for the reduced radial radiation to the outside.

[0042] The reflector device on the surfaces of the magnet arrangement facing the heat loss source can advantageously also be provided in a magnet arrangement of a traveling wave tube arrangement.

[0043] Fig. Figure 2 shows a partial and schematic representation of the structure of a traveling-wave tube arrangement with a device for dissipating waste heat according to the present invention. The traveling-wave tube arrangement contains, in the usual manner, a delay line VL in a vacuum chamber, for example in the form of a helical or comb line. The vacuum chamber with the delay line VL is surrounded by a magnet arrangement PP, which generates a magnetic field in the vacuum chamber in which an electron beam ES is guided on the central longitudinal axis of the vacuum chamber or the delay line VL. The electron beam ES is in the Fig. Electrons are fed from the left by an electron beam source (not shown) and, after passing through the delay line VL, are directed onto a collector KO. As the electron beam travels through the vacuum chamber, it interacts with a high-frequency signal fed into the delay line VL, which is coupled out in amplified form via an output HF. The electron beam moves against a delaying electrostatic field and transfers power to the delay line during its interaction. The electrons are collected in the collector KO, and their remaining energy is converted into heat within the collector KO. The collector can be made of copper, for example, and can also be constructed as a multi-stage collector in a known manner.

[0044] A radiant body SK is mounted on the outer surface of the collector KO and thermally connected to it. The radiant body SK consists of an AlSi alloy, the percentage of which is advantageously adjusted such that the coefficient of thermal expansion of the AlSi alloy differs from the coefficient of thermal expansion of the collector KO material by less than 30%, particularly less than 20%, and preferably less than 10%. The radiant body SK can advantageously rest against the outer surface of the collector under elastic preload and, in a preferred embodiment, can be slid over the collector at elevated temperature and shrunk onto the outer surface of the collector upon cooling. The radiant body SK can also be soldered to the outer surface of the collector.

[0045] The in Fig. 2 single-piece drawn radiation bodies SK can also be arranged analogously to the arrangement according to Fig. 1. The arrangement is radially divided into two parts with respect to the longitudinal axis, in that a base body made of AlSi is attached to the collector KO and an outer body having the radiator structures is attached to this base body.

[0046] The heat loss occurring in the collector during operation of the traveling wave tube arrangement is transferred via the collector, which consists of a highly thermally conductive material, and the good thermal conductivity connection between the collector and the radiating body SK, which is made of highly thermally conductive AlSi alloy material, to the radiation structures and is emitted there as radiation power into the environment, especially into space in the case of space applications of such a traveling wave tube arrangement.

[0047] The features specified above and in the claims, as well as those discernible from the illustrations, can be advantageously implemented both individually and in various combinations. The invention is not limited to the described embodiments but can be modified in many ways within the scope of expert knowledge. In particular, the reflector device in the ion accelerator arrangement can also be advantageously implemented independently of the Al-Si material choice.

Claims

[1] Device for dissipating waste heat from a heat source via a heat conduction arrangement to a heat sink, wherein the device is used in a spacecraft and the heat sink is the surrounding free space into which a radiant arrangement connected to the heat conduction arrangement emits thermal radiation, and wherein the heat conduction arrangement is thermally connected to a support structure which is arranged between the heat source and the heat conduction arrangement, and wherein the support structure and the heat conduction arrangement are made of different materials, characterized by that the heat conduction arrangement consists at least predominantly of an Al-Si alloy with a hypereutectic proportion of Si. [2] Device according to claim 1, characterized bythat the coefficient of thermal expansion of the Al-Si alloy differs by less than 30%, in particular less than 20%, preferably less than 10% from the coefficient of thermal expansion of the material of the support structure. [3] Device according to claim 1 or 2, characterized by , that a layer of another material is inserted at an interface between the support structure and the heat conduction arrangement, which has a higher ductility than the materials of the support structure and the heat conduction arrangement. [4] Device according to any one of claims 1 to 3, characterized by , that the heat conduction arrangement surrounds the support structure and is subject to elastic tension against the support structure. [5] Device according to claim 4, characterized by that the heat conduction arrangement is thermally shrunk onto the support structure. [6] Device according to any one of claims 1 to 5, characterized by, that the supporting structure surrounds a space containing the heat loss source laterally with respect to a longitudinal axis (LA). [7] Device according to any one of claims 1 to 6, characterized by that the heat conduction arrangement is soldered to the support structure. [8] Device according to any one of claims 1 to 7, characterized by that the support structure contains a magnetic arrangement between the heat loss source and the heat conduction arrangement. [9] Device according to any one of claims 1 to 7, characterized by , that the support structure is the collector electrode (CO) of a traveling wave tube. [10] Device according to claim 9, characterized by that the collector electrode (CO) consists at least predominantly of copper. [11] ion accelerator arrangement with a device for dissipating waste heat, with an ionization chamber (IK) containing a waste heat source and a surrounding magnet arrangement which also serves as a support structure, and with a heat conduction arrangement for dissipating waste heat accumulating at the chamber wall (KW), wherein the heat conduction arrangement is thermally conductive and mechanically firmly connected to the support structure and has a higher thermal conductivity and / or a lower specific weight compared to the support structure, characterized by , that the heat conduction arrangement consists at least predominantly of an aluminum-silicon alloy with a hypereutectic component of silicon, and / or that at least between a part of the surfaces of the magnet arrangement that are assigned to and spaced away from the chamber wall (KW) a heat radiation reflector device is arranged. [12] Arrangement according to claim 11, characterized bythat the proportion of silicon is at least 30%, in particular at least 40%. [13] Arrangement according to claim 11 or 12, characterized by that the proportion of silicon is at most 60%. [14] Arrangement according to any one of claims 11 to 13 characterized by , that the heat conduction arrangement surrounds the magnet arrangement and is radially clamped against it. [15] Arrangement according to claim 14, characterized by that the heat conduction arrangement is shrunk onto the magnet arrangement. [16] Arrangement according to any one of claims 11 to 15, characterized by that the material of the magnet arrangement has a coefficient of thermal expansion between 8×10 -6 / K and 16×10 -6 / K owns. [17] Arrangement according to any one of claims 11 to 16, characterized by , that the magnet arrangement contains several permanent magnet rings surrounding the ionization chamber (IK), which are spaced apart from each other in a longitudinal direction (LR) of the ionization chamber (IK). [18] Arrangement according to claim 17, characterized by , that in the longitudinal direction (LR) of the ionization chamber (IK) adjacent permanent magnet rings have polarities oriented in opposite directions in the longitudinal direction (LR). [19] Arrangement according to claim 17 or 18, characterized by , that pole shoe rings (PR) made of soft magnetic material are inserted between longitudinally adjacent permanent magnet rings (LR). [20] Arrangement according to any one of claims 11 to 19, characterized by , that the heat conduction arrangement is coupled with a radiator arrangement which emits heat into the environment by radiation. [21] Arrangement according to one of claims 11 to 20, comprising the heat radiation reflector device of claim 11, wherein the latter is located on surfaces of permanent magnet materials. [22] Arrangement according to one of claims 19 to 21, comprising the heat radiation reflector device of claim 11, wherein the latter is interrupted in longitudinal sections at the pole shoes (PR). [23] Arrangement according to one of claims 11 to 22, comprising the heat radiation reflector device of claim 11, wherein the latter is formed by a reflective coating (RE) on the magnet arrangement. [24] Arrangement according to any one of claims 11 to 23, characterized by their arrangement in a spacecraft.

Images