Thermal management device

Patent metadata

Field	Value
Publication number	US-10716246-B2
Application number	US-201816197775-A
Country	US
Kind code	B2
Filing date	Nov 21, 2018
Priority date	Dec 12, 2017
Publication date	Jul 14, 2020
Grant date	Jul 14, 2020

Abstract

A thermal management device for dissipating heat from one or more electrical components in an aircraft, the thermal management device including: a heat spreader with a plurality of layers of annealed pyrolytic graphite, the heat spreader having higher thermal conductivity in a plane defined by the layers than in a direction perpendicular to the layers; a flow path for a cooling fluid defined through the heat spreader, such that at least a portion of the flow path is surrounded by the heat spreader, wherein the flow path is helical, around a central axis extending through the plurality of layers; and a housing encasing the heat spreader, the housing arranged to have one or more electrical components mounted there-on and to form a thermal interface between the heat spreader and one or more electrical components.

First claim

The invention claimed is:

1. A thermal management device for dissipating heat from one or more electrical components in an aircraft, the thermal management device including:
a heat spreader comprising a plurality of layers of annealed pyrolytic graphite, the heat spreader having higher thermal conductivity in a plane defined by the layers than in a direction perpendicular to the layers;
a flow path for a cooling fluid defined through the heat spreader, such that at least a portion of the flow path is surrounded by the heat spreader, wherein the flow path is helical, around a central axis extending through the plurality of layers; and
a housing encasing the heat spreader, the housing arranged to have the one or more electrical components mounted there-on and to form a thermal interface between the heat spreader and the one or more electrical components,
wherein a pipe extends straight through the housing, and wherein the thermal management device further comprises:
a static helical baffle arranged on the exterior of the pipe;
a void formed in the heat spreader around the pipe and baffle; and
slots formed in a section of the pipe within the housing, to provide fluid communication between the interior of the pipe and the void,
wherein the flow path is defined on the exterior of the pipe, by the baffles.

2. The thermal management device of claim 1 , wherein the cooling fluid comprises aero-lubricant or aviation fuel.

3. The thermal management device of claim 1 , wherein the flow path contacts an internal surface of the housing at a plurality of points along the flow path.

4. The thermal management device of claim 3 , including recesses in an outer surface of the housing, where the thickness of the housing is reduced, wherein the recesses align with at least some of the contact points between the flow path and the housing.

5. The thermal management device of claim 1 , wherein the flow path is defined by the pipe carrying the cooling fluid passing through the housing.

6. The thermal management device of claim 5 , wherein the pipe extends outside the housing, and wherein portions of the pipe outside the housing are arranged for mounting the thermal management device to a cooling fluid and/or electrical system including the thermal management device.

7. The thermal management device of claim 5 , wherein the pipe is helical in shape, and the flow path is defined inside the pipe.

8. The thermal management device of claim 1 , wherein the housing comprises a plurality of faces, and at least two of the faces are arranged to have the one or more electrical components mounted thereon.

9. The thermal management device of claim 8 , wherein the housing comprises an elongate cuboid having four elongate sides arranged around the axial direction of the device,
wherein each of the elongate sides is arranged to have one or more electrical components mounted thereon.

10. The thermal management device of claim 1 , including:
an inlet in the housing for providing cooling fluid into the flow path; and
an outlet in the housing for exhaust cooling fluid form the flow path
wherein the fluid flows from the inlet to the outlet.

11. The thermal management device of claim 10 , wherein the flow path is arranged along a path axis extending from the inlet to the outlet, and wherein the path axis extends through the plurality of layers of the heat spreader.

12. The thermal management device of claim 1 , wherein the housing encapsulates the heat spreader.

13. A power converter including:
the one or more electrical components mounted on the thermal management device of claim 1 .

14. The power converter of claim 13 , wherein the housing of the thermal management device comprises a plurality of faces and the electrical components are mounted on two or more faces of the thermal management device.

15. The power converter of claim 13 , wherein the electrical components include one or more of: power modules; switches; capacitors; filters; gate drivers; bus bars; and sensors.

16. The power converter of claim 13 , wherein the electrical components are mounted concentrically around the thermal management device.

17. The power converter of claim 13 wherein the cooling fluid of the thermal management device comprises aero-lubricant or aviation fuel, the flow path of the thermal management device is defined by and inside a helical pipe carrying the cooling fluid passing through the housing of the thermal management device, and the power converter has one or more of the following features:
wherein the flow path has helix has a diameter of 43.18 mm;
wherein the pipe has a diameter of 19.05 mm;
where the pipe has a wall thickness of 1.78 mm;
wherein the flow path helix has a pitch of 33.02 mm;
wherein the helix has seven complete revolutions.

Assignees

• Rolls Royce Plc

Inventors

• Muthu Vivek
• Gajanayake Chandana J
• Chatterjee Pradip

Classifications

• H10W40/47

  by flowing liquids, e.g. forced water cooling · CPC title

• H10W40/25

  characterised by their materials · CPC title

• H10W40/22

  characterised by their shape, e.g. having conical or cylindrical projections · CPC title

• H10W40/40 Primary

  involving heat exchange by flowing fluids · CPC title

• H05K7/20872

  Liquid coolant without phase change · CPC title