Aircraft heat exchangers

1. A turbine engine heat exchanger comprising:

a manifold having a first face and a second face opposite the first face;

a plurality of first plates along the first face, each first plate having an interior passageway;

a plurality of second plates along the second face, each second plate having an interior passageway; and

a first flowpath passing through the interior passageways of the first plates, the manifold, and the interior passageways of the second plates,

wherein:

the manifold forms a transfer plenum into which respective first flowpath legs through the first plates merge and from which respective second flowpath legs through the second plates split,

the manifold forms an inlet plenum from which respective first flowpath legs through the first plates split; and

the manifold forms an outlet plenum into which respective first flowpath legs through the second plates merge.

2. The turbine engine heat exchanger of claim 1 wherein:

the first flowpath passes sequentially through:

the interior passageways of the first plates;

the manifold; and

the interior passageways of the second plates.

3. The turbine engine heat exchanger of claim 1 wherein:

the first face is concave and the second face is convex.

4. The turbine engine heat exchanger of claim 1 wherein:

the first plates and the second plates comprise castings.

5. The turbine engine heat exchanger of claim 1 wherein:

the first plates and the second plates each have:

a proximal edge mounted to the manifold and an opposite distal edge;

a forward edge and an aft edge; and

an inlet to the respective first passageway and an outlet from the respective first passageway;

the first plates' outlets are along the associated first plate proximal edge, forward of the first plates' inlets;

the second plates' inlets are along the associated second plate proximal edge; and

the second plates' outlets are forward of the second plates' inlets.

6. The turbine engine heat exchanger of claim 1 wherein:

the first plates are circumferentially arrayed in at least one first bank; and

the second plates are in at least one second bank, wherein within each second bank the second plates share a common parallel orientation.

7. The turbine engine heat exchanger of claim 6 wherein:

within each respective bank all plates are joined by wave fins.

8. A turbine engine including the turbine engine heat exchanger of claim 1 and further comprising:

one or more fan sections;

one or more compressor sections aft and downstream of the one or more fan sections along a core flowpath;

a combustor section downstream of the one or more compressor sections along the core flowpath;

one or more turbine sections downstream of the combustor section along the core flowpath;

an outer bypass flowpath;

an inner bypass flowpath; and

a wall between the outer bypass flowpath and the inner bypass flowpath, wherein:

exteriors of the first plates are along the inner bypass flowpath; and

exteriors of the second plates are along the outer bypass flowpath.

9. The turbine engine of claim 8 wherein:

the first flowpath is a compressor bleed flowpath.

10. The turbine engine of claim 9 wherein:

the first flowpath provides turbine cooling.

11. The turbine engine of claim 8 wherein:

the inner bypass flowpath extends from a stage of the one or more fan sections; and

the outer bypass flowpath extends from another stage of the one or more fan sections upstream of said stage.

12. The turbine engine of claim 11 wherein:

the first flowpath extends from within or downstream of the one or more compressor sections.

13. The turbine engine of claim 8 wherein:

the first plates and the second plates each have:

an inner diameter edge and an outer diameter edge; and

an inlet to the respective first passageway and an outlet from the respective first passageway;

the first plates' outlets are along the associated first plate outer diameter edge, forward of the first plates' inlets;

the second plates' inlets are along the associated second plate inner diameter edge; and

the second plates' outlets are forward of the second plates' inlets.

14. The turbine engine of claim 13 wherein:

the first plates' inlets are along the associated first plate outer diameter edge.

15. The turbine engine of claim 13 wherein:

the second plates' outlets are along the associated second plate inner diameter edge.

16. A method for using the turbine engine of claim 8 , the method comprising running the turbine engine to:

transfer thermal energy from a flow along the first flowpath to an inner bypass flow along the inner bypass flowpath and an outer bypass flow along the outer bypass flowpath.

17. The method of claim 16 wherein the running of the turbine engine further comprises:

passing the outer bypass flow to the heat exchanger at a first temperature and first pressure;

passing the inner bypass flow to the heat exchanger at a second temperature and second pressure greater than the first temperature and first pressure, respectively; and

passes passing the flow along the first flowpath to the heat exchanger at a third temperature and third pressure greater than the second temperature and second pressure, respectively.

18. The method of claim 16 wherein:

the flow is generally counterflow to the inner bypass flow and outer bypass flow.

19. A turbine engine heat exchanger comprising:

a manifold having a first face and a second face opposite the first face;

a plurality of first plates along the first face, each first plate having an interior passageway;

a plurality of second plates along the second face, each second plate having an interior passageway; and

a first flowpath passing through the interior passageways of the first plates, the manifold, and the interior passageways of the second plates,

wherein:

the manifold forms an inlet plenum from which respective first flowpath legs through the first plates split;

the manifold forms a transfer plenum into which respective first flowpath legs through the first plates merge and from which respective second flowpath legs through the second plates split;

the first plates are joined by wave fins having peaks secured to one joined plate and troughs secured to the other joined plate; and

the second plates are joined by wave fins having peaks secured to one joined plate and troughs secured to the other joined plate.

20. The turbine engine heat exchanger of claim 19 wherein:

the first face is concave and the second face is convex;

the first plates are circumferentially arrayed in at least one first bank; and

the second plates are in at least one second bank, wherein within each second bank the second plates share a common parallel orientation.