Phase change material (PCM)-based conductive thermal actuator switches and associated stacked and arrayed systems
An apparatus includes a thermal actuator switch configured to control a transfer of thermal energy through the thermal actuator switch. The thermal actuator switch includes first and second plates and a piston movable laterally between the first and second plates. The thermal actuator switch also includes a phase change material configured to (i) expand to move a surface of the piston into a first position and (ii) contract to allow the surface of the piston to move into a second position. The surface of the piston thermally contacts the first plate and increases thermal energy transfer between the first and second plates when in one of the first and second positions. The surface of the piston is spaced apart from the first plate and decreases thermal energy transfer between the first and second plates when in another of the first and second positions.
1. An apparatus comprising:
a thermal actuator switch configured to control a transfer of thermal energy through the thermal actuator switch, the thermal actuator switch comprising:
a first plate and a second plate, the first plate separated from the second plate by a thermally-insulative material;
an enclosed internal cavity defined by each of the first plate and the second plate;
a piston at least partially disposed within the internal cavity and movable laterally between the first plate and the second plate, and
a phase change material at least partially disposed within the internal cavity and configured to (i) expand to move a surface of the piston into a first position and (ii) contract to allow the surface of the piston to move into a second position, the surface of the piston thermally contacting the first plate and increasing thermal energy transfer between the first plate and the second plate when in one of the first position and the second position, the surface of the piston spaced apart from the first plate and decreasing thermal energy transfer between the first plate and the second plate when in another of the first position and the second position.
2. The apparatus of claim 1 , wherein:
the piston comprises a head coupled to a plunger by a shaft; and
the phase change material is configured to push against the plunger to move the piston closer to the first plate.
3. The apparatus of claim 1 , wherein:
the piston comprises a head coupled to a plunger by a shaft configured to contact the phase change material; and
the plunger comprises a plurality of fins extending toward the head and configured to contact the phase change material.
4. The apparatus of claim 3 , wherein the thermal actuator switch further comprises a soft or pliant material in one of the first plate and the second plate, the plunger configured to contact the soft or pliant material.
5. The apparatus of claim 1 , wherein at least one of the first plate and the second plate comprises a plurality of fins extending into the internal cavity and configured to contact the phase change material.
6. The apparatus of claim 1 , wherein the thermal actuator switch further comprises at least one heat strap coupling at least one of the first plate and the second plate to the piston.
7. The apparatus of claim 1 , wherein the thermally-insulative material comprises a thermally-insulative epoxy.
8. The apparatus of claim 1 , wherein the internal cavity defined between the first plate and the second plate comprises one of:
a vacuum; or
one or more gases configured to inhibit thermal energy transfer between the piston and the first plate.
9. The apparatus of claim 1 , wherein the thermal actuator switch further comprises at least one heat strap extending through at least one of the first plate and the second plate.
10. A system comprising:
at least one heat source;
at least one heat sink; and
multiple thermal actuator switches configured to control a transfer of thermal energy between the at least one heat source and the at least one heat sink, each of the thermal actuator switches comprising:
a first plate and a second plate, the first plate separated from the second plate by a thermally-insulative material;
an enclosed internal cavity defined by each of the first plate and the second plate;
a piston at least partially disposed within the internal cavity and movable laterally between the first plate and the second plate; and
a phase change material at least partially disposed within the internal cavity and configured to (i) expand to move a surface of the piston into a first position and (ii) contract to allow the surface of the piston to move into a second position, the surface of the piston thermally contacting the first plate and increasing thermal energy transfer between the first plate and the second plate when in one of the first position and the second position, the surface of the piston spaced apart from the first plate and decreasing thermal energy transfer between the first plate and the second plate when in another of the first position and the second position.
11. The system of claim 10 , wherein, in each thermal actuator switch:
the piston comprises a head coupled to a plunger by a shaft; and
the phase change material is configured to push against the plunger to move the piston closer to the first plate.
12. The system of claim 10 , wherein, in each thermal actuator switch:
the piston comprises a head coupled to a plunger by a shaft configured to contact the phase change material; and
the plunger comprises a plurality of fins extending toward the head and configured to contact the phase change material.
13. The system of claim 12 , wherein, in each thermal actuator switch, the thermal actuator switch further comprises a soft or pliant material in one of the first plate and the second plate, the plunger configured to contact the soft or pliant material.
14. The system of claim 10 , wherein, in each thermal actuator switch, at least one of the first plate and the second plate comprises a plurality of fins extending into the internal cavity and configured to contact the phase change material.
15. The system of claim 10 , wherein, in each thermal actuator switch, the thermal actuator switch further comprises at least one of:
one or more heat straps coupling at least one of the first plate and the second plate to the piston; and
one or more heat straps extending through at least one of the first plate and the second plate.
16. The system of claim 10 , wherein, in each thermal actuator switch, the thermally-insulative material comprises a thermally-insulative epoxy.
17. The system of claim 10 , wherein, in each thermal actuator switch, the internal cavity defined between the first plate and the second plate comprises one of:
a vacuum; or
one or more gases configured to inhibit thermal energy transfer between the piston and the first plate.
18. The system of claim 10 , wherein at least some of the thermal actuator switches are arranged in parallel between the at least one heat source and the at least one heat sink.
19. The system of claim 10 , wherein at least some of the thermal actuator switches are arranged in a stacked configuration between the at least one heat source and the at least one heat sink.
20. A method comprising:
receiving thermal energy at a thermal actuator switch from at least one heat source; and
controlling a transfer of the thermal energy between the at least one heat source and at least one heat sink using the thermal actuator switch;
wherein the thermal actuator switch comprises:
a first plate and a second plate, the first plate separated from the second plate by a thermally-insulative material;
an enclosed internal cavity defined by each of the first plate and the second plate;
a piston at least partially disposed within the internal cavity that moves laterally between the first plate and the second plate; and
a phase change material at least partially disposed within the internal cavity that (i) expands to move a surface of the piston into a first position and (ii) contracts to allow the surface of the piston to move into a second position, the surface of the piston thermally contacting the first plate and increasing thermal energy transfer between the first plate and the second plate when in one of the first position and the second position, the surface of the piston spaced apart from the first plate and decreasing thermal energy transfer between the first plate and the second plate when in another of the first position and the second position.