THERMAL DEVICE FOR A FLUID, WITH BAFFLES, AND ASSOCIATED CIRCUITS
20180238635 ยท 2018-08-23
Assignee
Inventors
- Fabrice Chopard (Paris, FR)
- Paul Bline (Paris, FR)
- Boris Chauvet (Paris, FR)
- Christophe Dominiak (Paris, FR)
Cpc classification
B60H1/3202
PERFORMING OPERATIONS; TRANSPORTING
Y02E60/14
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
F28D20/021
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01M2011/0025
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01P11/20
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01M2011/0016
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01M5/021
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F28D2020/0082
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F28D20/026
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F28D2020/0078
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01M11/0004
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60H1/00492
PERFORMING OPERATIONS; TRANSPORTING
International classification
F28D20/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01M5/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01P11/20
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A thermal device comprising a fluid circulation circuit in which the fluid circulates over time at different temperatures, and a thermal store and heat exchanger arranged on said circuit and enclosing an interior volume in which the fluid circulates, and in which are arranged elements that store and release thermal energy, of PCM type, in contact with the fluid, for heat exchanges. The interior volume of the store and heat exchanger is provided with baffles.
Claims
1. Thermal device for a refrigerant or heat transfer fluid, the device comprising: a circuit for circulating said fluid, in which the fluid circulates over time at different temperatures, a thermal store and heat exchanger arranged on said circuit and enclosing an interior volume: in which only the fluid circulates, between an inlet and an outlet, and in which PCM is arranged, for a heat exchange with said fluid which is the only one to circulate between each other, characterised in that: the PCM is arranged, within said interior volume, in a plurality of elements that store and release thermal energy, of modular construction, the thermal store and heat exchanger comprises several adjacent modules, structurally separate and of which at least some individually comprise a base separating two adjacent modules, each base: splitting the volume into a succession of sub-volumes, in which are arranged said elements that store and release thermal energy, around and/or wherein the fluid circulates, in heat exchanges with each other, and having at least one passage for communicating between the sub-volumes, and, for creating baffles in thermal store and heat exchanger on the fluid path: passages for communicating between the sub-volumes are offset from a following passage, and/or inside the corresponding module, and for creating other sub-volumes there, partitions stand which keep communications between said other sub-volumes, for the circulation of the fluid.
2. Thermal device according to claim 1, in which the elements that store and release thermal energy are individualised structures that have exterior surfaces formed to keep a space between two of said elements, in which space the fluid can circulate.
3. Thermal device according to claim 1, in which the elements that store and release thermal energy comprise beads.
4. Thermal device according to claim 1: in which the store and heat exchanger has at least one peripheral wall interleaved between the interior volume of the outside, and the device further comprises at least one first layer containing a PCM and at least one second layer containing a thermally-insulating material which surrounds said interior volume.
5. Thermal device according to claim 4, in which said at least one peripheral wall contains a mouldable polymer material and the at least one first and second layers are integrated with said polymer material.
6. Thermal device according to claim 4, in which said at least one peripheral wall belongs to an exterior protective casing surrounding all the modules of the store and heat exchanger and which integrates or is lined by said at least one first and second layer(s).
7. Thermal device according to claim 4, in which each one of the modules of the store and heat exchanger comprises said peripheral wall which integrates or is lined by said at least one first and second layer(s).
8. Thermal device according to claim 1, in which the circuit is a circuit for cooling by a heat transfer liquid, such as water, an engine on a vehicle, the circuit comprising a path for circulating the liquid and, arranged on the path: in series, a means for circulating the liquid on the path, an engine of which components are to be placed in heat exchange with the liquid and a radiator that has an inlet and an outlet for said liquid in order to place it in heat exchange with another fluid, assembled on a first branch, between the inlet and the outlet of the radiator, the thermal store and heat exchanger according to one of the preceding claims.
9. Thermal device for a refrigerant or heat transfer fluid, the device comprising a circulation circuit, in which a fluid circulates over time at different temperatures, and which, on a vehicle engine, is a lubrication circuit whereon are arranged, in fluid communication, functional components of the engine to be lubricated, a lubricant crankcase and a thermal store and heat exchanger, wherein said fluid only circulates, the thermal store and heat exchanger including: an interior volume: in which the lubricant circulates, between an inlet and an outlet, and in which are arranged, a plurality of elements having PCM, and that store and release thermal energy, in said interior volume, partitions which split the volume into a succession of sub-volumes with communications between them, for the circulation in baffles of the lubricant, around and/or in the elements that store and release thermal energy which are distributed in the sub-volumes, to thermally exchange with the lubricant, and, in the lubricant crankcase, with lubricant circulation stopped, said elements that store and release said thermal energy are immersed in a first lubricant volume outside which a second lubricant volume lays superior to the first volume.
10. Thermal device according to claim 9, in which, around said interior volume, at least one layer containing a thermally-insulating material is contained in an envelope sealed against the material and against air, such that with an air gap being created in said envelope, a VIP panel is constituted.
11. Thermal device according to claim 9, in which: the functional components of the engine are located in an engine block, the lubricant crankcase is screwed to the engine block, under said engine block, and contains a lubricant bath, and the thermal store and heat exchanger is arranged in the lubricant crankcase, to send the lubricant towards the engine block, after which it has circulated in said thermal store and heat exchanger.
12. Motor vehicle comprising a thermal device for a lubricating fluid, the device comprising a lubrication circuit, in which the lubricating fluid circulates over time at different temperatures, and whereon are arranged, in fluid communication: functional components of the engine to be lubricated, located in an engine block, a lubricant crankcase screwed to the engine block, under it, containing a lubricant bath, and a thermal store and heat exchanger including an interior volume wherein only the lubricant circulates, between an inlet and an outlet, a plurality of elements having PCM, and that store and release thermal energy, being arranged in the interior volume, which is split by the partitions into a succession of sub-volumes with communications between the sub-volumes, for the circulation in baffles of the lubricant, around and/or in the elements that store and release thermal energy which are distributed in said sub-volumes, to thermally exchange with the lubricant, the thermal store and heat exchanger being arranged in the lubricant crankcase, to send the lubricant towards the engine block, after it has circulated in said thermal store and heat exchanger.
13. Lubricant crankcase connected to a circuit for lubricating a vehicle engine whereon are arranged, in fluid communication, said lubricant crankcase and functional components of the engine to be lubricated, located in an engine block, characterised in that: the lubricant crankcase contains a thermal store and heat exchanger wherein only said lubricant circulates, before which it is sent towards the engine block, said thermal store and heat exchanger including the interior volume, wherein only the lubricant circulates, between an inlet and an outlet, a plurality of elements having PCM, and that store and release thermal energy, being arranged in the interior volume, which is split by partitions into a succession of sub-volumes with communications between the sub-volumes, for the circulation in baffles of the lubricant, around and/or in the elements that store and release thermal energy, which are distributed into said sub-volumes, to thermally exchange with the lubricant, and, with the lubricant circulation stopped, the lubricant crankcase contains a first lubricant volume and a second lubricant volume, said elements that store and release said thermal energy being immersed in said first volume outside of which lays, in the lubricant crankcase, the second lubricant volume which is superior to the first volume.
14. Motor vehicle comprising a thermal device for a lubricating fluid, the device comprising a lubrication circuit, in which the lubricating fluid circulates over time at different temperatures, and whereon are arranged, in fluid communication: functional components of the engine to be lubricated, located in an engine block, and the lubricant crankcase according to claim 13, which is screwed to the engine block, under it, and which contains a lubricant bath, in which the thermal store and heat exchanger is arranged.
Description
[0061] If necessary, the different aspects of the invention will be best understood and other characteristics, details and advantages of it will again appear upon reading the description will follows, produced as a non-exhaustive example and in reference to the appended drawings wherein:
[0062]
[0063]
[0064]
[0065] and
[0066] The diagram in
[0067] The device 1 comprises: [0068] a circulation circuit 300 of the fluid 9, in which the fluid circulates over time at different temperatures, [0069] and a thermal store and heat exchanger 10 arranged on the circuit 300.
[0070] The store and heat exchanger (or unit that stores and releases energy) 10 is a unit which will store thermal energy through phase change(s) of at least one PCM, then later, release a part at least of this energy through new phase change(s) (at least some) of this/these PCM(s).
[0071] The store and heat exchanger 10 therefore encloses an interior volume 7, in which the fluid 9 circulates and in which are arranged elements 13 having PCM that store and release thermal energy, and which are in contact with the fluid, for heat exchanges.
[0072] The interior volume 7 of the store and heat exchanger is provided with baffles. To define them, the store and heat exchanger 9 can have, on the fluid path, a series of partitions 29, as in
[0075] The fluid 9 circulating in and between the (sub)volumes can be liquid (water, oil) or gaseous (such as air).
[0076] So that the figures are legible,
[0077]
[0078] Each module 3 is constituted by a lateral peripheral wall 5 that completes the bored base 29.
[0079] Each transversal wall 29 and the crossing passage 30 thereof, thus form a decelerator to the free circulation of the fluid between the inlet 33 thereof and the outlet 35 thereof. Preferably, two successive passages 30 will be laterally offset as schematised. Opposite the base, each module is open, in 31, such that, exiting a passage 30, the fluid arrives directly in the interior volume of the adjacent module. The circulation in the store/exchanger, between the sub-volumes, can be in series or in parallel.
[0080] In the variant in
[0081] In each case, as constituting the elements 13, a rubber composition such as defined in EP2690137 or in EP2690141 can be provided, namely in the second case, a crosslinked composition with the basis of at least one RTV (room temperature vulcanisation) silicone elastomer and comprising at least one phase change material (PCM), said at least one silicone elastomer having a viscosity measured at 25 C. according to the standard ISO 3219 which is less than or equal to 5000 mPa.Math.s.
[0082] In this composition, the elastomer matrix will mainly be constituted of one or several RTV silicone elastomers. The thermal phase change material (PCM) can be constituted of n-hexadecane, or of a lithium salt, all having melting points of less than 40 C.
[0083] As an alternative, the PCM of the elements 13 could be fatty acid-based, paraffin-based, or eutectic or hydrated salt-based, or even fatty alcohol-based, for example.
[0084] In particular, for ease with implementing and optimising exchange surfaces, the elements 13 are here presented as individualised structures that have exterior surfaces, here convex, formed to keep a space 130 between them, in which the fluid can circulate (see
[0085] A very favourable solution is thus that these elements 13 are presented as beads. Spherical beads are favoured in the preferred example illustrated. The elements 13 could have crossing passages (bored beads, for example).
[0086] In principle, individualised structures 13, here these beads of spheres, will be arranged loosely in the sub-volumes, such as 7a, 7b, etc.
[0087] An active thermal barrier (15/23) will favourably ensure a thermal insulation of the store and heat exchanger 10 against the outside.
[0088] This active thermal barrier will either be integrated to the lateral peripheral wall 5 (as in
[0089] In principle, the second layer 23 will be, there where the two layers exist and if only two such layers exist, arranged around the first layer 15. Thus, it can be arranged such that an excessively cold or hot outside temperature only slightly interferes with that in the volume(s) 7, the first layer 15 acting as an accumulator/delayer in variation of the temperature in this/these volume(s) and within the fluid.
[0090] In order to optimise this process, it is recommended that the active thermal barrier comprises at least one VIP panel forming a pocket 19 in a controlled atmosphere, in which will be arranged at least the second layer 23, it will preferably coexist with the PCM layer 15 within the sealed envelope 37.
[0091] The second layer 23 will favourably be a porous, thermally-insulating material, against which the envelope 37 will be sealed. Once the air gap is created in the envelope, a VIP panel will be constituted.
[0092] The thermally-insulating material 23 will favourably be composed of a nanostructure material, such as a silica powder or an aerogel, confined in a deformable or conformable sheet which will not let water vapour or gases pass through. The VIP obtained will be emptied of the air thereof to obtain, for example, a pressure of a few millibars, then it can be sealed. Typically, the thermal conductivity A of such a VIP will be 0.004/0.008 W/m.Math.K. Using vacuum insultation panels should enable a thermal resistance R=5 m.sup.2.Math.K/W to be achieved, with only 20 to 30 mm of insulator.
[0093] The example could be applied here, of VIP panels and superinsulation materials, which are supplied in PCT/FR2014/050267 and in WO2014060906 (porous material), respectively.
[0094] The solutions presented above must enable, in an acceptable volume and weight, in particular by aircraft or automotive manufacturers, a quick storage of thermal energy available after around 6-10 minutes, maintaining this energy for 12 to 15 hours, before the quick release thereof, typically for a few minutes (in particular, less than 2/3 minutes), for example, to an engine during a cold start phase.
[0095] It is also recommended that thus designed, the store/exchangers 10 will favourably meet the need to introduce size parameters such as RTD (resident time distribution) in the blocks and NTU (number of transfer units/blocks) to facilitate a change in scale without modifying the thermal and hydrodynamic elements obtained during a qualification. With an identical reproduction of a flow in volumes 7a, 7b, etc. of different sizes being impossible, except for breaking down a total volume into identical sub-elements, the solutions above can enable to consider without the effects in scales of identical PCM loading and unloading kinetics.
[0096] To complete their fulfilment,
[0097] Like in the embodiments illustrated, each body 3 will favourably be one-piece. It can be made from plastic, metal (stainless steel, aluminium) or composite, in particular. A moulded production will be preferred. In this case, it is provided that the peripheral wall 5 contains a mouldable polymer material (for example, a polyamide or a poly(p-phenylene sulphide, fibre-charged or not), in which the first and/or second layers 15, 23 can be integrated, as provided in the embodiment in
[0098] The reference to a body made from mouldable material covers thermoplastic resins that are fibre-charged and injected, and also thermosetting resins, impregnating a fabric or a material, such as a woven or non-woven fabric.
[0099] Integrated or not in the wall of the components 3, at least the second insulating layer 23, and preferably the two layers 15/23, will favourably be vacuum surrounded in one or several pockets 19 therefore known here as VIP-constituted (being specified that the partial gap could be replaced by a controlled atmosphere: the volume would be filled by a gas that has a thermal conductivity of less than that of ambient air, 26 mW/m.Math.K).
[0100] In this regard, pockets, structurally separate from each other, as in
[0101] In
[0102] Even if one single PCM (based) layer 15 is represented as in
[0103] Each pocket 19 comprises: [0104] at least one first element, or first layer 15, therefore containing the PCM, to the side of which is arranged the second layer made from an insulating material 23 (porous, if there is a gap), and [0105] at least one closed exterior envelope 37 which contains the first and second elements and is constituted of at least one deformable or conformable sheet 49, sealed against the PCM, with: [0106] a) either said sheet 49 which is additionally sealable (thermally/chemically, in 49a, 49b around the pocket), as shown in
[0108] The sheet(s) or film(s) 49 and 53 can typically be made as a multilayer film comprising polymer films (PE and PET) and aluminium in laminated form, for example (sheet that is around ten micrometres thick) or metal form (vacuum deposit of a film that is a few dozen nanometres thick).
[0109] Two examples of application will now be given, in line with
[0110] Thus, a vehicle 60, such as a car, can be seen in
[0111]
[0112] In the two cases, the circuit 300 defines a path for circulating a fluid whereon are arranged, in fluid communication with each other, an oil crankcase 74 and functional components of the engine to be oiled, such as connecting-rod bearings and crankshaft bearings, but also the camshaft and the drive device 76 thereof. The crankcase 74, of which the tank (metal, in principle) is screwed under the engine block 720, with a seal, contains the oil necessary to lubricate the mobile elements of the bottom-engine and the top-engine. Oil is drawn here by the suction strainer of the oil pump 78 which distributes it under pressure, preferably via an oil filter, to the different components (crankshaft, connecting rods, camshaft, etc.). The oil can then sink simply through gravity; arrows 80.
[0113] In the version in
[0114] In the second assembly, schematised in
[0115] In
[0116] The store and heat exchanger is almost that of
[0117] Laterally all around, but also under and above it, via, for example, crankcase covers such as that 32 with a single or multiple pocket(s) and VIP-constituted 34 (as in
[0118] In principle, the internal volume of the crankcase 74 will be fixed by the manufacturer of the vehicle.
[0119] Yet, producing a vehicle lubricant tank which could enable to heat the lubricant while the outside temperature is very cold, for example, 5 to 10 C., and while the vehicle has been stopped, sitting at this temperature, for example, for 6 to 8 hours, was a challenge.
[0120] A solution has been given here, by providing both, favourably, and as schematised in
[0123] In particular, during an engine start, the PCM(s) of said elements 13 will thus still be hot: they will have kept the latent heat coming from the end of the previous functioning of the engine block provided from said lubricant crankcase. The first lubricant volume (V1) will therefore be hotter than the second (V2), by heat exchange with the elements 13 immersed in it.
[0124] But, the second exterior lubricant volume (V2) being constructed bigger than the first volume (V1), it has been chosen to multiply and extend the fluid/PCM exchange zones, from there the baffles 12 via an internal partitioning which is schematised in
[0125] In this way, at the time of starting a new cycle (after stopping mentioned above by cold time), by progressive mixing via circulation in the circuit, the total lubricant in circulation (V1+V2) can quickly be hot throughout, with advantages in terms of rate of the engine to be lubricated and limitation of pollutants.
[0126] In the enlarged extract in
[0127] In
[0128] The circuit comprises a path 4 for circulating the liquid and, arranged on the path: [0129] in series, a means 6 for circulating the liquid on a path, the engine 2 of which the components are to be placed in heat exchange with the liquid 9 which circulates and a radiator 8 that has a liquid inlet 8a and a liquid outlet 8b in order to place it in heat exchange with another fluid 90, [0130] assembled on a first branch 12, between the inlet and outlet of the radiator, the thermal store and heat exchanger (or unit) 10.
[0131] The term radiator includes: [0132] both a general automotive or aeroplane radiator of the (air) fluid/liquid (glycoled water) exchanger type, [0133] that the liquid/liquid exchangers as on maritime structures, such as boats, in which the radiator will typically be a liquid (seawater)/liquid (freshwater) exchanger.
[0134] In addition, two assemblies of the circuit are possible:
[0135] With the assembly in
[0139] With the assembly in
[0145] Preferably, the physical parameter to choose in the unit 10 and the radiator to control the loading of thermal units, more or less quickly or completely from the unit 10 will be a temperature in the radiator 8, preferably an exit temperature.
[0146] And, favourably, in nominal functioning, the first valve 14 will distribute, between the radiator 8 and said second branch 22, the circulation of the liquid exiting the engine according to temperature data connected to the radiator. A temperature sensor 26 is provided for this (
[0147] Furthermore, in nominal functioning, if a power problem occurs on the radiator 8 due to a thermal overload detected by a temperature sensor (such as the sensor 26), the fourth valve 20 will close and the third valve 18 will open, to ensure a circulation of liquid in the unit 10 (via the first branch 12) after passing into the radiator (
[0148] Then (see
[0149] Concerning the thermal efficiency of the unit 10 in one of the circuits, it will again be noted that the/each unit module can be thermally-insulated from the outside (EXT) by the barrier complex 15/23 favourably comprising an aerogel VIP 23 of thermal conductivity equal to 6-8 mW/mK at 25 C., 15-20 mm thick surrounding an elastomer-based layer 15 loaded with 80-90% by PCM mass, enthalpically microencapsulated equal to 200-240 kJ/kg, 2.5-5.5 mm thick. The initial quantity of stored energy of 1.5-2 MJ for the oil can be maintained with a SOC (state of charge) at 65-75% above 15 hours, thus enabling the release of very efficient new energy. This energy can be released in less than 2/3 minutes to maximise the reduction of CO.sub.2 emission in the case of a cold start of the engine, for example.
[0150] Regarding
[0151] All the superimposed modules 3 (even as here, the functionalised column 88 arranged opposite them), without therefore interfering with their internal volumes, are surrounded by the peripheral wall 500 of a protective casing 96 containing or lined inside, on all faces of the casing and almost continually, for the thermal management complex 15/23 having PCM and VIP pockets in a controlled atmosphere, 19 or 50.