Acoustic absorber with integrated heat sink

Patent metadata

Field	Value
Publication number	US-11204204-B2
Application number	US-201916296412-A
Country	US
Kind code	B2
Filing date	Mar 8, 2019
Priority date	Mar 8, 2019
Publication date	Dec 21, 2021
Grant date	Dec 21, 2021

Abstract

A thermal management assembly is provided for both removing heat and absorbing acoustic energy. The thermal management assembly includes a heat sink base component and a plurality of thermally conductive fins disposed in a sparsely-arranged array in thermal communication with the heat sink base component. Each fin defines a two-sided Helmholtz unit cell disposed in a periodic array extending from the heat sink base component. Each unit cell includes a lossy resonator and a lossless resonator. The lossy resonator includes a first chamber portion bounded by at least one first boundary wall defining a first chamber volume, and a first neck forming an opening in the first chamber portion. The lossless resonator includes a second chamber portion bounded by at least one second boundary wall defining a second chamber volume, and a second neck forming an opening in the second chamber portion.

First claim

What is claimed is:

1. A thermal management assembly for removing heat and absorbing acoustic energy, the thermal management assembly comprising:
a heat sink base component; and
a plurality of thermally conductive fins disposed in a sparsely-arranged periodic array in thermal communication with, and extending from, the heat sink base component, each fin defining a two-sided Helmholtz unit cell that comprises:
a lossy resonator having:
a first chamber portion bounded by at least one first boundary wall defining a first chamber volume; and
a first neck forming an opening in the first chamber portion and providing fluid communication between the first chamber portion and an ambient environment; and

a lossless resonator having:
a second chamber portion bounded by at least one second boundary wall defining a second chamber volume; and
a second neck forming an opening in the second chamber portion and providing fluid communication between the second chamber portion and the ambient environment.

2. The thermal management assembly according to claim 1 , wherein the heat sink base component defines first and second opposing major surfaces, the first major surface being provided in thermal communication with a heat generating device, and the second major surface being coupled with the plurality of fins.

3. The thermal management assembly according to claim wherein the heat generating device comprises an electronics component.

4. The thermal management assembly according to claim 2 , wherein the sparsely-arranged periodic array is positioned in an annular pattern, with the first necks of the lossy resonators directed toward a center of the sparsely-arranged periodic array.

5. The thermal management assembly according to claim 1 , wherein the fins are spaced apart by a center-to-center periodic distance, P, wherein the periodic distance, P, is greater than a maximum lateral width dimension, W, of each unit cell.

6. The thermal management assembly according to claim 5 , wherein the sparsely-arranged period array is characterized by a fill factor equal to W/P, and wherein the fill factor is 0.5 or less.

7. The thermal management assembly according to claim 1 , wherein within each fin, the second chamber volume is greater than the first chamber volume, a length of the first neck is greater than a length of the second neck, and the lossy resonator and the lossless resonator have the same resonance frequency.

8. The thermal management assembly according to claim 1 , wherein the heat sink base component and the plurality of fins are formed as a unitary, monolithic component.

9. The thermal management assembly according to claim 1 , comprising first and second sets of a plurality of fins, wherein:
the first set of the plurality of fins is disposed in a first annular periodic array, and configured with a first frequency;
the second set of the plurality of fins is disposed in a second annular periodic array, surrounding the first annular periodic array, and configured with a second frequency different from the first frequency;
the first necks of the lossy resonators are directed toward a common center of the first and second sets of the plurality of fins; and
the first and second sets of the plurality of fins are arranged in a staggered relationship.

10. The thermal management assembly according to claim 1 , wherein the fins are aligned in a plurality of sparsely-arranged linear rows, wherein each row is configured for absorbing acoustic energy of a different frequency, and wherein the sparsely-arranged linear rows are arranged in a staggered relationship.

11. The thermal management assembly according to claim 1 , wherein within each fin, the first boundary wall, the second boundary wall, and an interior partition wall cooperate to form a unit cell having a cross-section defining an elongated oval shape enclosing the lossy resonator and the lossless resonator with the lossy resonator and the lossless resonator separated by the interior partition wall, and the first neck and the second neck disposed at opposing ends.

12. The thermal management assembly according to claim 1 , wherein the first boundary wall, the second boundary wall, and an interior partition wall cooperate to form a unit cell having a cross-section defining a non-square, rectangular shape enclosing the lossy resonator and the lossless resonator with the lossy resonator and the lossless resonator separated by the interior partition wall.

13. The thermal management assembly according to claim 1 , wherein the first boundary wall and the second boundary wall cooperate to form a unit cell having a cross-section defining two equilateral parallelograms with the first neck and the second neck disposed at opposing ends.

14. A thermal management assembly for removing heat and absorbing acoustic energy, the thermal management assembly comprising:
a heat sink base component defining first and second opposing major surfaces;
a heat generating device in thermal communication with the first major surface; and
a plurality of thermally conductive fins disposed in a sparsely-arranged periodic array and in thermal communication with the heat sink base component and extending from the second major surface of the heat sink base component, each fin defining a two-sided Helmholtz unit cell that comprises:
a lossy resonator having:
a first chamber portion bounded by at least one first boundary wall defining a first chamber volume; and
a first neck forming an opening in the first chamber portion and providing fluid communication between the first chamber portion and an ambient environment; and

a lossless resonator having:
a second chamber portion bounded by at least one second boundary wall defining a second chamber volume; and
a second neck forming an opening in the second chamber portion and providing fluid communication between the second chamber portion and the ambient environment.

15. The thermal management assembly according to claim 14 , wherein the fins are positioned in an annular pattern, with the first necks of the lossy resonators directed toward a center of the sparsely-arranged periodic array.

16. The thermal management assembly according to claim 14 , wherein the heat sink base component and the plurality of tins are formed as a unitary, monolithic component.

17. The thermal management assembly according to claim 14 , wherein the fins are aligned in a plurality of sparsely-arranged linear rows. wherein each row is configured for absorbing acoustic energy of a different frequency, and wherein the sparsely-arranged linear rows are arranged in a staggered relationship.

18. The thermal management assembly according to claim 14 , wherein within each fin, the first boundary wall, the second boundary wall, and an interior partition wall cooperate to form a unit cell having a cross-section defining an elongated oval shape enclosing the lossy resonator and the lossless resonator with the lossy resonator and the lossless resonator separated by the interior partition wall, and the first neck and the second neck disposed at opposing ends.

19. A method of removing heat from a heat generating device and suppressing sound from an air circulation device, the method comprising:
positioning a heat sink adjacent a heat generating device, the heat sink including a base component with a plurality of thermally conductive fins extending therefrom in a sparsely-arranged periodic array, wherein each fin comprises a two-sided Helmholtz unit cell that comprises:
a lossy resonator having:
a first chamber po

Assignees

• Toyota Eng & Mfg North America

Inventors

• Lee Taehwa
• Iizuka Hideo
• Dede Ercan Mehmet

Classifications

• F28F2265/28

  for preventing noise · CPC title

• F28F3/04

  the means being integral with the element · CPC title

• F01N1/023 Primary

  Helmholtz resonators · CPC title

• H05K1/0209

  External configuration of printed circuit board adapted for heat dissipation, e.g. lay-out of conductors, coatings · CPC title

• F28F3/042

  in the form of local deformations of the element · CPC title