The invention will now be explained in more detail with reference to the appended schematic Figures, in which:
FIG. 1 shows a first embodiment of the invention, in which air cooled by means of a liquid cooling system is directed on to an electronic device;
FIG. 2 shows a second embodiment of the invention, in which air flows over an electronic device and is then cooled by a liquid cooling system;
FIG. 3 shows a third embodiment of the invention, in which coolant is supplied by a liquid cooling system to a heat exchanger in a housing with a plurality of electronic devices arranged one above the other;
FIG. 4 shows a fourth embodiment of the invention similar to the third embodiment, in which a fan is arranged in the housing above the heat exchanger;
FIG. 5 shows a fifth embodiment of the invention, in which coolant flows through a board of an electronic device;
FIG. 6 shows a sixth embodiment of the invention, in which coolant flows in the outer region of a housing in which an electronic device is arranged;
FIG. 7 shows a seventh embodiment of the invention, in which the electronic device is arranged on a heat sink through which coolant flows;
FIG. 8 shows an eighth embodiment of the invention similar to the seventh embodiment, in which a plurality of electronic devices are arranged on the heat sink;
FIG. 9 shows a ninth embodiment of the invention, in which coolant flows around an electronic device, and
FIG. 10 shows a tenth embodiment of the invention, in which a plurality of electronic devices are cooled successively or in parallel in a cooling circuit.
FIG. 1 shows a liquid cooling system 2 which supplies coolant to a heat exchanger 8 via a feed line 4, which coolant is returned from the heat exchanger 8 to the liquid cooling system 2 via a return line 6. The liquid cooling system 2 cools the coolant and delivers it again. In the resulting cooling circuit the coolant is permanently in the liquid state. It is to be understood that in a different embodiment the coolant may vaporise at least partially in the heat exchanger 8. The heat exchanger 8 draws in warm air via an intake conduit 12, which warm air is cooled as it passes through the heat exchanger 8, and is directed by a discharge conduit 10 on to an electronic device 14 with a plurality of components. In this embodiment the electronic device 14 and its components 16 are cooled convectively. The heat exchanger 8 is located in proximity to the electronic device 14, so that only a short intake conduit 12 and discharge conduit 10 are required. The air exiting the heat exchanger 8 may cool a plurality of electronic devices 14.
FIG. 2 shows a further embodiment of the aircraft electronics cooling apparatus. A liquid cooling system 2 supplies coolant to a heat exchanger 8 via a feed line 4, which coolant is returned to the liquid cooling system 2 via a return line 6. Air from the cabin at cabin air temperature enters a housing 18 via at least one opening 20 in the housing 18, in which an electronic device 14 with a plurality of electronic components 16 is arranged. The air flows past the components 16 of the electronic device 14, cooling the components 16 and the whole electronic device 14. The air flowing past the electronic device 14 enters the heat exchanger via an intake conduit 12, is cooled in the heat exchanger to the cabin air temperature and re-enters the cabin via a discharge conduit 10. In some applications the usual cabin air temperature in an aircraft is sufficient to cool an electronic device. In this embodiment a neutral temperature compensation process which does not thermally influence the cabin air-conditioning system is produced for the aircraft cabin. An advantage of this embodiment is that no cold zones, on which condensate can collect, are produced on the electronic device 14 and/or on its components 16. Condensate can cause failure of a component 16 or of the electronic device 14. The air entering the heat exchanger 8 may cool a plurality of electronic devices 14.
FIG. 3 shows a third embodiment of the inventive aircraft electronics cooling apparatus. A plurality of electronic devices 14 with a plurality of electronic components 16 are arranged in a housing 22. At least one lower opening 26 is located in the lower region of the housing 22 and at least one upper opening 28 is located in the upper region of the housing 22. A heat exchanger 24 is arranged between the at least one lower opening 26 and the plurality of electronic devices 14. A liquid cooling system 2 supplies coolant to the heat exchanger 24 via a feed line 4, which coolant is returned to the liquid cooling system 2 via a return line 6. In this embodiment cooling takes place by free convection. The warm air with low density exits the housing 22 through the plurality of upper openings 28. At the same time air enters through the plurality of lower openings 26 of the housing 22, is cooled by the heat exchanger 24 and flows to the electronic devices 14 and their components 16 to be cooled.
FIG. 4 shows a fourth embodiment of the inventive aircraft air-conditioning system which is similar to the embodiment of FIG. 3 and additionally includes a fan 30 which is arranged in the housing 22 between the heat exchanger 24 and the plurality of electronic devices 14 with a plurality of components 14. The fan 30 generates an air flow which is directed towards the electronic devices 14 to be cooled. Air enters the housing via the plurality of lower openings 26, passes through the heat exchanger 24 and flows around the electronic devices 14 and their components 16 in order to cool same, and exits the housing 22 through the upper openings 28.
FIG. 5 shows a fifth embodiment of the inventive aircraft electronics cooling apparatus. An electronic device 14 comprises a plurality of components 16 which are arranged on a board 32. The board 32 is in the form of a heat exchanger and coolant flows at least partially through said heat exchanger. A liquid cooling system 2 supplies coolant to the board 32 via a feed line 4, which coolant cools the components 16 arranged on the board 32. The coolant may also flow through at least one component 16 which is arranged on the board 32. The coolant exits the board into a return line 6 and is returned to the liquid cooling system 2.
FIG. 6 shows a sixth embodiment of the inventive aircraft electronics cooling assembly, in which an electronic device with a plurality of components 16 is arranged in a housing 34. Coolant flows at least partially through the outer region of the housing 34, or at least a housing wall. A liquid cooling system 2 supplies coolant via a feed line 4 to the housing 34. The housing and also the electronic device 14 in the housing are thereby cooled. The coolant exits the housing 34 into a return line 6 and is returned to the liquid cooling system. In this embodiment the electronic device 14 is completely uncoupled from the environment. This embodiment may be used with electronic devices which must ensure especially high security against failure and/or which control or monitor safety-relevant functions.
FIG. 7 shows a seventh embodiment of the invention, in which an electronic device 14 is arranged on a heat sink 36, e.g. a cooling body. FIG. 8 shows an eighth embodiment of the invention, in which a plurality of electronic devices 14, 14a, 14b are arranged on a heat sink 36a. A liquid cooling system 2 supplies coolant via a feed line 4 to the heat sink 36, 36a, on which at least one electronic device 14, 14a, 14b is arranged. The heat sink extracts heat from the at least one electronic device 14, 14a, 14b and dissipates it to the coolant. The coolant flows back to the liquid cooling system 2 via a return line 6. These embodiments have the advantage that it is not necessary to open the cooling circuit in order to exchange the electronic device 14, 14a, 14b. This gives rise to an aircraft electronics cooling apparatus which is especially maintenance-friendly. However, it is not ruled out in these embodiments that individual components 16 are supplied with coolant separately.
FIG. 9 shows a ninth embodiment of the inventive aircraft electronics cooling apparatus, in which an electronic device is arranged in a housing 38, the coolant flowing through the interior of the housing 38. A liquid cooling system 2 supplies coolant to the housing 38 via a feed line 4. In the interior of the housing 38 the coolant flows around the electronic device and its components 16. However, the electronic device 14 may also be sealed, so that the components 16 do not come into contact with the coolant. The coolant extracts heat from the electronic device 14 and its components 16, respectively, and flows back to the liquid cooling system 2 via a return line 6. In this embodiment an especially large amount of heat is extracted from the electronic device 14 and its components 16, so that this embodiment is especially suitable for electronic devices which must provide high electronic performance or have high power dissipation. In this embodiment the electronic device must be so constructed that the coolant has no influence on the operability of the electronic device. This requirement is met, for example, by a dielectric cooling liquid and/or an electrically non-conductive cooling liquid.
FIG. 10 shows an inventive aircraft electronics cooling apparatus in which the coolant provides cooling in series and in parallel to a plurality of electronic devices in a cooling circuit. Via a feed line 4 a liquid cooling system 2 supplies coolant in parallel to a plurality of electronic devices 40a, 40b, 40c, through the boards of which coolant flows, as explained previously with reference to the fifth embodiment. The coolant flows through the plurality of electronic devices 40a, 40b, 40c in parallel, ensuring higher redundancy and security against failure The coolant also flows to an electronic device 42 which is arranged on a heat sink through which coolant flows, as explained previously with reference to the seventh embodiment. The coolant then flows into the outer region of a housing in which an electronic device 44 is located, as explained previously with reference to the sixth embodiment. The coolant then flows to a further electronic device 40d which is so configured that the coolant can flow through the board thereof in order to cool the electronic device 40d, as explained previously with reference to the fifth embodiment. The coolant then flows back to the liquid cooling system 2 via a return line 6. The electronic devices 42, 44, 40d connected in series to one another may be located at different sites in the aircraft. Because of the high flexibility of the inventive aircraft electronics cooling apparatus, electronic devices which are located at practically any desired site in the aircraft can be cooled. It is to be understood that, in order to increase the safety and redundancy of the inventive aircraft electronics cooling apparatus, all the electronic devices may also be supplied with coolant in parallel.
The coolant utilised in the aircraft electronics cooling apparatus is preferably a dielectric liquid. The dielectric liquid does not affect the operation of the electronic devices and their components. The coolant preferably has a temperature from approximately +10° C. to approximately +20° C. An example of a dielectric liquid is Galden® HT 135 or ZT 130 of Solvay Solexis.
In an embodiment the coolant delivered by the liquid cooling system may be permanently in the liquid state. In this embodiment thermodynamic parameters such as boiling temperature and the like do not need to be considered. Moreover, in this embodiment, as explained previously, a plurality of electronic devices to be cooled may be located serially in a cooling circuit.
In another embodiment, however, the aircraft electronics cooling apparatus may be so configured that the coolant delivered by the liquid cooling system vaporises at least partially while cooling the electronic device. With this embodiment higher cooling capacities can be achieved and larger quantities of heat transported away.
Patent Application
20080055852
