Crossflow heat exchanger with stacked distribution tubes

1. A heat exchanger comprising:

a core having a front end and a back end that are depthwise spaced apart from each other, a first side and a second side that are width-wise spaced apart from each other, a top and a bottom that are heightwise spaced apart from each other;

an inlet header that is a first tubular manifold located at the top of the core and extending along the front end of the core, between the first and second sides of the core, through which a working fluid flows,

plural of sets of inlet tubes, extending height-wise from the header along the front end of the core, between the top and bottom of the core, and each of the sets of inlet tubes are width-wise spaced apart from each other along the inlet header,

each of the plural inlet tubes include a first inlet tube positioned depthwise against the front end of the heat exchanger, a second inlet tube positioned depthwise against the first inlet tube and a third inlet tube positioned depthwise against the second inlet tube, wherein the plural inlet tubes are fluidly isolated from each other away from the inlet header;

an outlet header that is a second tubular manifold located at the bottom of the core and extending along the back end of the core between the first and second sides of the core through which the working fluid flows,

plural sets of outlet tubes extending height-wise from the header along the back end of the core, between the top and bottom of the core, and each of the sets of outlet tubes are width-wise spaced apart from each other along the inlet header to align with ones of the sets of inlet tubes,

each of the plural outlet tubes include a first outlet tube positioned depthwise against the back end of the heat exchanger, a second outlet tube positioned depthwise against the first outlet tube and a third outlet tube positioned depthwise against the second outlet tube, wherein the plural outlet tubes are fluidly isolated from each other away from the outlet header,

wherein the first inlet and outlet tubes have a same length as each other, the second inlet and outlet tubes have the same length as each other and are longer than the first inlet and outlet tubes, and the third inlet and outlet tubes have a same length as each other and are longer than the second inlet and outlet tubes; and

core channels, within the core that extend depthwise from the front end to the back end of the heat exchanger,

wherein the core channels are fluidly isolated from each other within the core and connect the inlet tubes to the outlet tubes such that: the first inlet tube and third outlet tube are connected by the channels; the second inlet tube and second outlet tube are connected by the channels; and the third inlet tube and first outlet tube are connected by the channels.

2. The heat exchanger of claim 1 , wherein:

the inlet tubes and the outlet tubes each define a header end and a terminal end; and

each tube tapers towards the terminal end.

3. The heat exchanger of claim 1 , wherein the heat exchanger is a counterflow heat exchanger.

4. The heat exchanger of claim 1 , wherein:

each of the inlet tubes are connected to a same number of the core channels; and

each of the outlet tubes are connected to a same number of the core channels.

5. The heat exchanger of claim 1 , further comprising:

a first baffle on one side of the core channels; and

a second baffle on another side of the core channels,

wherein the first and second baffles are configured to direct a gas flow between the front end and the back end of the heat exchanger.

6. The heat exchanger of claim 5 , including:

a first set of heat fins that are coupled to the core channels and the first baffle; and

a second set of heat fins that are coupled to the core channels and the second baffle.

7. The heat exchanger of claim 1 , including a case extending from the front end to the back end to surround the core and form a flow boundary for the gas flow.

8. The heat exchanger of claim 1 , wherein the manifolds, tubes and channels each have a circular cross section.

9. A method of manufacturing a heat exchanger, comprising:

defining the heat exchanger of claim 1 ; and

additively manufacturing the heat exchanger.

10. The method of claim 9 , comprising defining the heat exchanger such that:

the inlet tubes and the outlet tubes each define a header end and a terminal end; and

each tube tapers towards the terminal end.

11. The method of claim 9 , comprising defining the heat exchanger such that the heat exchanger is a crossflow heat exchanger.

12. The method of claim 9 , comprising defining the heat exchanger such that:

each of the inlet tubes are connected to a same number of the core channels; and

each of the outlet tubes are connected to a same number of the core channels.

13. The method of claim 9 , comprising defining the heat exchanger to include:

a first baffle on one side of the core channels; and

a second baffle on another side of the core channels,

wherein the first and second baffles are configured to direct a gas flow between the front end and the back end of the heat exchanger.

14. The method of claim 13 , comprising defining the heat exchanger to include:

a first set of heat fins that are coupled to the core channels and the first baffle; and

a second set of heat fins that are coupled to the core channels and the second baffle.

15. The method of claim 9 , comprising defining the heat exchanger to include a case extending from the front end to the back end to surround the core and form a flow boundary for the gas flow.

16. The method of claim 9 , wherein the manifolds, tubes and channels each have a circular cross section.

17. The heat exchanger of claim 1 , wherein the front end and back end of the core are each square shaped.

18. The method of claim 9 , wherein the front end and back end of the core are each square shaped.