HEAT EXCHANGERS
A heat exchanger which may be used in an engine, such as a vehicle engine for an aircraft or orbital launch vehicle. is provided. The heat exchanger may be configured as generally drum-shaped with a multitude of spiral sections, each containing numerous small diameter tubes. The spiral sections may spiral inside one another. The heat exchanger may include a support structure with a plurality of mutually axially spaced hoop supports, and may incorporate an intermediate header. The heat exchanger may incorporate recycling of methanol or other antifreeze used to prevent blocking of the heat exchanger due to frost or ice formation.
1 . A heat exchanger, comprising: at least one first conduit section for the flow of a first fluid in heat exchange with a second fluid in a flow path which passes the at least one first conduit section; and a support for the at least one first conduit section, wherein the at least one first conduit section is mounted at a first location to the support, and the at least one first conduit section at a second location thereon is movable relative to the support in response to thermal change.
2 . A heat exchanger as claimed in claim 1 , wherein the at least one first conduit section comprises a plurality of tubes for heat exchange.
3 . A heat exchanger as claimed in claim 2 , wherein the tubes are connected at a first end thereof to an inlet header and at a second end thereof to an outlet header of the at least one first conduit section.
4 . A heat exchanger as claimed in claim 3 , wherein the first location is at one of the inlet and outlet headers, which is fixedly mounted to the support, the other of the inlet and outlet headers being movable relative to the support in response to thermal change.
5 . A heat exchanger as claimed in claim 4 , wherein the other of the headers is mounted to a movable support therefor which is movable relative to the support.
6 . A heat exchanger as claimed in claim 2 , wherein the at least one first conduit section comprises a spiral section having a plurality of the tubes extending along in a spiral shape alongside and spaced from one another in rows.
7 . A heat exchanger as claimed in claim 6 , wherein the tubes in the at least one first conduit section are arranged in between 1 and 40 rows spaced from one another in a radial direction.
8 . A heat exchanger as claimed in claim 5 , wherein the tubes are arranged in about 10 to 1000 rows spaced from one another in an axial direction.
9 . A heat exchanger as claimed in claim 2 , wherein the tubes are about 1 to 3 metres long and extend from a first header to a second header.
10 . A heat exchanger as claimed in claim 2 , wherein the tubes have a diameter which is about 1 mm.
11 . A heat exchanger as claimed in claim 2 , wherein the tubes have a wall thickness of about 20 to 40 microns.
12 . A heat exchanger as claimed in claim 6 , comprising a plurality of said spiral sections internested and oriented angularly spaced relative to one another.
13 . A heat exchanger as claimed in claim 12 , wherein said spiral sections are configured in the shape of a generally cylindrical drum.
14 . A heat exchanger as claimed in claim 12 , wherein the support comprises at least one circular hoop to which the at least one first conduit section is secured.
15 . A heat exchanger as claimed in claim 14 , wherein the support comprises a plurality of said circular hoops which are configured spaced apart from one another in a generally cylindrical perforated drum structure and in which a header of the at least one first conduit section is fixed to the plurality of said circular hoops.
16 . A heat exchanger as claimed in claim 3 , wherein at least one of said inlet header and said outlet header is substantially rigid and is fluidly coupled to a flexible conduit.
17 . A heat exchanger as claimed in claim 16 , wherein the flexible conduit is fluidly coupled to a substantially rigid manifold.
18 . A heat exchanger as claimed in claim 17 , wherein the substantially rigid manifold is fixed axially in position relative to the support but is free to radially move.
19 . A heat exchanger as claimed in claim 6 , wherein the rows of tubes in the at least one first conduit section comprise a plurality of rows spaced from one another by spacers arranged to counter aerodynamic load applied to the tubes.
20 . A heat exchanger as claimed in claim 6 , further comprising a load element between tubes of two adjacent said first conduit sections for transmitting load therebetween while allowing relative sliding motion therebetween in response to thermal change.
21 . A heat exchanger as claimed in claim 20 , wherein the load element is substantially aligned with the spacers to form a generally radially extending load path structure for reaction against aerodynamic load applied to the tubes while allowing relative movement between adjacent said first conduit sections in response to thermal change.
22 . A heat exchanger as claimed in claim 21 , further comprising a plurality of said load elements configured in a series in which they are spaced generally circumferentially from one another.
23 . A vehicle engine, comprising: a combustion section; and a heat exchanger as claimed in claim 1 , wherein the heat exchanger is adapted to cool air as the second fluid in a flow path directed towards the combustion section.
24 . A vehicle engine as claimed in claim 23 , further comprising a helium supply for providing helium as the first fluid.
25 . A flying machine, comprising a heat exchanger as claimed in claim 1 .
26 . A flying machine, comprising a vehicle engine as claimed in claim 23 .
27 . A heat exchanger, comprising: a plurality of first conduit sections for the flow of a first fluid in heat exchange with a second fluid in a flow path which passes the first conduit sections; and a support for the plurality of first conduit sections, each of the first conduit sections comprising a plurality of tubes for heat exchange, each first conduit section comprising a spiral section having a plurality of the tubes extending along in a spiral shape alongside and spaced from one another in rows, wherein at least one load element is provided between tubes in mutually radially spaced rows for countering aerodynamic load applied to the tubes.
28 . A heat exchanger as claimed in claim 27 , wherein said at least one load element comprises a spacer fixing together tubes in radially spaced rows.
29 . A heat exchanger as claimed in claim 27 , wherein said at least one load element comprises an element provided between tubes of two adjacent said first conduit sections for transmitting load therebetween while allowing relative sliding motion therebetween in response to thermal change.
30 . A heat exchanger as claimed in claim 29 , wherein said element is fixed to a tube in one of said first conduit sections and slidably engages another of said first conduit sections.
31 . A heat exchanger as claimed in claim 27 , wherein said at least one load element comprises at least one I-beam-shaped element.
32 . A heat exchanger as claimed in claim 27 , wherein the tubes in one of said first conduit sections are arranged in between 2 and 40 rows spaced from one another in a radial direction.
33 . A heat exchanger as claimed in claim 27 , wherein the tubes are about 1 to 3 metres long from a first header to a second header.
34 . A heat exchanger as claimed in claim 27 , wherein the tubes have a diameter which is about 1 mm.
35 . A heat exchanger as claimed in claim 27 , wherein the tubes have a wall thickness of about 20 to 40 microns.
36 . A heat exchanger as claimed in claim 27 , wherein the tubes are arranged in about 10 to 1000 rows spaced from one another in an axial direction.
37 . A heat exchanger as claimed in claim 27 , wherein said spiral sections are internested with and oriented angularly spaced relative to one another.
38 . A heat exchanger as claimed in claim 27 , wherein said spiral sections are configured in the shape of a cylindrical drum.
39 . A heat exchanger as claimed in claim 27 , wherein the support comprises at least one circular hoop to which a one of the first said conduit sections is secured.
40 . A heat exchanger as claimed in claim 39 , wherein the support comprises a plurality of circular hoops which are configured spaced apart from one another in a generally cylindrical perforated drum structure, and in which at least one longeron member is provided for engagingly supported an adjacent said tube at a location substantially radially aligned with said at least one load element.
41 . A heat exchanger as claimed in claim 27 , wherein a plurality of said load elements are provided in a generally radially extending load path structure for reaction against aerodynamic load applied to the tubes.
42 . A heat exchanger as claimed in claim 41 , wherein the load path structure is adapted to permit relative movement between tubes of adjacent first conduit sections in response to thermal change.
43 . A vehicle engine, comprising: a combustion section; and a heat exchanger as claimed in claim 27 , wherein the heat exchanger is adapted to cool air, as the second fluid, in a flow path directed towards the combustion section.
44 . A vehicle engine as claimed in claim 43 , further comprising a helium supply for providing helium as the first fluid.
45 . A flying machine, comprising a heat exchanger as claimed in claim 27 .
46 . A flying machine, comprising an engine as claimed in claim 43 .
47 . A heat exchanger, comprising: at least one first conduit section for the flow of a first fluid in heat exchange with a second fluid in a flow path which passes the at least one first conduit section, in which each first conduit section comprises a flow path via at least one tube from an inlet to an outlet; and an intermediate header provided in the flow path between the inlet and outlet for flow communication with an intermediate fluid flow path.
48 . A heat exchanger as claimed in claim 47 , wherein each of the inlet and outlet comprises a header tube.
49 . A heat exchanger as claimed in claim 48 , wherein the header tubes are straight.
50 . A heat exchanger as claimed in claim 48 , wherein the at least one first conduit section comprises a plurality of first flow tubes extending from the inlet to the intermediate header for flow therebetween and a plurality of second flow tubes extending from the intermediate header to the outlet for flow therebetween.
51 . A heat exchanger as claimed in claim 50 , wherein the length of one first flow tube plus the length of one second flow tube is about 2 to 3 metres.
52 . A heat exchanger as claimed in claim 50 , wherein the first flow tubes and/or the second flow tubes are about 1 mm in diameter.
53 . A heat exchanger as claimed in claim 50 , wherein the first flow tubes and/or the second flow tubes have wall thickness of about 20 to 40 microns.
54 . A heat exchanger as claimed in claim 50 , wherein each said first conduit section comprises a spiral section having the first and second flow tubes extending in a generally spiral shape alongside and spaced from one another in rows.
55 . A heat exchanger as claimed in claim 47 , further comprising a controller for controlling pressure in the intermediate flow path.
56 . A heat exchanger as claimed in claim 55 , wherein the controller comprises a flow valve.
57 . A heat exchanger as claimed in claim 47 , wherein the intermediate header comprises an outer enclosure for enclosing first fluid and an injector for injecting intermediate fluid flow into the outer enclosure, the injector comprising a tube having a series of flow apertures spaced therealong for injecting fluid into the outer enclosure.
58 . A heat exchanger as claimed in claim 57 , wherein each of the outer enclosure and the injector comprises a straight elongate tube.
59 . A heat exchanger as claimed in claim 58 , comprising a plurality of rows of tubes spaced apart from one another along the longitudinal direction of the outer enclosure, the tubes in said spaced apart rows being fluidly coupled to the outer enclosure at respective spaced locations along the length thereof.
60 . A heat exchanger, comprising: at least one first conduit section for the flow of a first fluid in heat exchange with a second fluid in a flow path which passes the at least one first conduit section, wherein each first conduit section comprises a flow path via at least one tube from an inlet to an outlet, wherein at least one of said tubes has first and second portions extending therealong which are formed of different materials to one another.
61 . A method of operating a heat exchanger as claimed in claim 47 , comprising flowing helium through the at least one first conduit section and through the intermediate fluid flow path.
62 . A method of operating a heat exchanger as claimed in claim 61 , which comprises flowing air as the second fluid in the flow path past the at least one first conduit section.
63 . An engine, comprising a combustion section and a heat exchanger as claimed in any claim 47 , wherein the heat exchanger is adapted to cool air as the second fluid in a flow path directed towards the combustion section.
64 . An engine as claimed in claim 63 , further comprising a helium supply for providing helium as the first fluid.
65 . A flying machine, comprising a heat exchanger as claimed in claim 47 .
66 . A flying machine, comprising an engine as claimed in claim 63 .
67 . A support structure for a heat exchanger, the heat exchanger comprising at least one first conduit section for the flow of a first fluid in heat exchange with a section fluid in a flow path which passes the at least one first conduit section, the support structure comprising a generally cylindrical perforated drum structure.
68 . A support structure as claimed in claim 67 , further comprising a plurality of mutually axially spaced hoop supports.
69 . A support structure as claimed in claim 68 , further comprising a plurality of mutually radially spaced longeron members which are adapted to supportingly engage the at least one first conduit section at a generally radially aligned load path structure.
70 . A support structure as claimed in claim 68 , wherein the hoop supports are formed with bearers and/or attachment structure for locating header tubes of the first conduit sections on the hoop supports.
71 . A support structure as claimed in claim 69 , wherein the hoop supports and longeron members are configured with generally rectangular or square flow spaces therebetween.
72 . A support structure as claimed in claim 71 , further comprising at least one diagonally mounted bracing element extending across at least one of the spaces.
73 . A support structure as claimed in claim 72 , wherein each said space has two diagonally mounted bracing elements configured in an X configuration thereby providing four substantially triangular flow apertures in the region of each said space.
74 . A heat exchanger for cooling a fluid in a flow path and containing a component liable to phase change below a temperature thereof, the heat exchanger comprising a series of tubes for the passage of coolant and an injector for introducing an anti-freeze component into the fluid in the flow path.
75 . A heat exchanger as claimed in claim 74 , wherein the injector comprises an antifreeze injector, wherein the antifreeze injector comprises a methanol injector arranged for connection to a source of methanol.
76 . A heat exchanger as claimed in claim 75 , further comprising a removal arrangement for removing liquid located within a body of moving fluid within the flow path.
77 . A heat exchanger as claimed in claim 76 , wherein the removal arrangement is located downstream of the injector.
78 . A heat exchanger as claimed in claim 76 , wherein the removal arrangement comprises at least one catcher element arranged to extend generally transverse to a general flow direction of the fluid therepast.
79 . A heat exchanger as claimed in claim 78 , comprising at least one row of said catcher elements.
80 . A heat exchanger as claimed in claim 79 , wherein the catcher elements are spaced apart in the row by a spacing distance which is less than the maximum cross-dimension of each said catcher element in the direction of spacing.
81 . A heat exchanger as claimed in claim 80 , wherein the spacing distance is about one quarter, one third or half of said maximum cross-dimension.
82 . A heat exchanger as claimed in claim 80 , wherein the catcher arrangement comprises a second row of catcher elements, the second row of catcher elements being staggered, in a direction from one catcher element to another along a row, with the first row of catcher elements.
83 . A heat exchanger as claimed in claim 82 , wherein the catcher elements in the first and second rows are spaced from the catcher elements in the same row substantially the same distance that they are spaced from the catcher elements in the other row.
84 . A heat exchanger as claimed in claim 78 , wherein the at least one catcher element has a longitudinal extent and has at least one point therealong a substantially circular cross section.
85 . A heat exchanger as claimed in claim 84 , wherein the at least one catcher element comprises a hollow tube having at least one liquid collection pocket located on an exterior surface thereof.
86 . A heat exchanger as claimed in claim 85 , wherein the hollow tube is hydroformed of metallic material.
87 . A heat exchanger as claimed in claim 85 , wherein the at least one liquid collection pocket comprises a scavenge aperture communicating from the liquid collection pocket into an interior conduit of the hollow tube, the scavenge aperture area being of small size for limiting airflow drawn thereinto with liquid.
88 . A heat exchanger as claimed in claim 85 , further comprising a mesh covering the at least one liquid collection pocket, with a cavity formed between the pocket and the mesh.
89 . A heat exchanger as claimed in claim 88 , wherein the mesh is an approximately 25 micron to 100 micron mesh.
90 . A heat exchanger as claimed in claim 88 , wherein the mesh is coated with a wetting agent.
91 . A heat exchanger as claimed in claim 89 , wherein the mesh is generally flat in the region of each pocket.
92 . A heat exchanger as claimed in claim 85 , further comprising a suction system fluidly connected to the hollow tube for removing liquid from the at least one liquid collection pocket.
93 . A heat exchanger as claimed in claim 76 , further comprising a second removal arrangement which is located downstream of said removal arrangement.
94 . A heat exchanger as claimed in claim 93 , wherein the antifreeze injector comprises a plurality of injection portions and is arranged to inject a more concentrated antifreeze at a first injection portion in a first region of air flow and a more water-diluted antifreeze at a second injection portion which is more upstream than the first injection portion at a second region of air flow that is warmer than the first region.
95 . A heat exchanger as claimed in claim 94 , further comprising a recycle path for recycling antifreeze and liquid water removed from air flow at the second removal arrangement for re-injection, upstream of the first removal arrangement, at the second injection portion, wherein each such re-injection in a plural sequence of such re-injections having the antifreeze more dilute, into warmer air and more upstream in the airflow than upon the previous injection, the antifreeze being re-injectable along a sequence of re-injection points along a path that is counter to the direction of air flow through the heat exchanger.
96 . A heat exchanger as claimed in claim 74 , which is adapted to cool air to below 0 degrees C.
97 . A heat exchanger as claimed in claim 78 , which is adapted to cool air to or to below about minus 100 degrees C.
98 . A heat exchanger as claimed in claim 97 , further comprising a control for controlling the environment in the vicinity of the coldest catcher element to be about 80 mol % or about 88 wt % methanol, on a water-methanol solid-liquid phase diagram, as temperature approaches about minus 100 degrees C.
100 . A heat exchanger as claimed in claim 78 , wherein the removal arrangement comprises a sufficient number of catcher elements to remove over 90% of water content from air passing through the heat exchanger.
101 . A heat exchanger assembly with a longitudinal extent in a longitudinal direction thereof, comprising: at least one generally annular heat exchanger module arranged to communicate with a longitudinally extending duct; at least one guide vane for turning flow between one and the other selected from (a) generally radial through the heat exchanger module and (b) generally longitudinal along the longitudinally extending duct.
102 . A heat exchanger assembly as claimed in claim 101 , wherein the guide vane is adapted to turn flow from generally radial to generally longitudinal.
103 . A heat exchanger assembly as claimed in claim 101 , wherein the guide vane is annular.
104 . A heat exchanger assembly as claimed in claim 101 , wherein the guide vane has a leading edge and a trailing edge and is of substantially constant thickness between the leading edge and the trailing edge.
105 . A heat exchanger assembly as claimed in claim 104 , wherein the leading edge is arranged at an angle of about 5 to 20 degrees relative to a radial direction.
106 . A heat exchanger assembly as claimed in claim 104 , wherein the trailing edge is arranged at an angle of about 5 to 15 degrees to the longitudinal direction.
107 . A heat exchanger assembly as claimed in claim 101 , wherein the guide vane has a longitudinal extent in the longitudinal direction and in which the guide vane comprises a curvedly-flaring leading section that is substantially an arc in cross section, and a substantially conical trailing section, the trailing section extending for about 50 to 85% of the longitudinal extent.
108 . A heat exchanger assembly as claimed in claim 101 , further comprising a plurality of guide vanes arranged in a mutually overlapped series along the longitudinally extending duct.
109 . A heat exchanger assembly as claimed in claim 108 , wherein the vanes are arranged with a narrowing therebetween so as to accelerate flow.
110 . A heat exchanger assembly as claimed in claim 101 , further comprising a plurality of heat exchanger modules arranged in a series along and around said longitudinally extending duct, and a series of guide vanes is provided extending adjacent and at least substantially the full longitudinal extent of at least one of said heat exchanger modules.
111 . An engine, comprising a heat exchanger as claimed in claim 101 , wherein the heat exchanger is located upstream of an air compressor and/or combustion stage of the engine.
112 . An engine, comprising a combustion section and a heat exchanger as claimed in claim 75 , wherein the heat exchanger is adapted to cool air in a flow path directed towards the combustion section.
113 . An engine as claimed in claim 112 , further comprising a helium supply for providing helium as coolant flowable through the heat exchanger.
114 . A flying machine, comprising a heat exchanger as claimed in claim 75 .
115 . A flying machine, comprising an engine as claimed in claim 111 .