Electroactive polymer devices for moving fluid
The invention describes devices for performing thermodynamic work on a fluid, such as pumps, compressors and fans. The thermodynamic work may be used to provide a driving force for moving the fluid. Work performed on the fluid may be transmitted to other devices, such as a piston in a hydraulic actuation device. The devices may include one or more electroactive polymer transducers with an electroactive polymer that deflects in response to an application of an electric field. The electroactive polymer may be in contact with a fluid where the deflection of the electroactive polymer may be used to perform thermodynamic work on the fluid. The devices may be designed to efficiently operate at a plurality of operating conditions, such as operating conditions that produce an acoustic signal above or below the human hearing range. The devices may be used in thermal control systems, such as refrigeration system, cooling systems and heating systems.
1. A device for performing thermodynamic work on a fluid, the device comprising:
one or more transducers, each transducer comprising at least two electrodes and an electroactive polymer in electrical communication with the at least two electrodes, wherein a portion of the electroactive polymer is arranged to deflect from a first position to a second position in response to a change in electric field, and wherein the electroactive polymer has an elastic modulus below about 100 MPa; and
at least one surface in contact with a fluid and operatively coupled to the one or more transducers, wherein the deflection of the portion of the electroactive polymer causes the thermodynamic work to be imparted to the fluid and wherein the thermodynamic work is transmitted to the fluid via the at least one surface.
2. The device of claim 1 , further comprising:
a chamber for receiving the fluid wherein a bounding surface of the chamber includes the at least one surface.
3. The device of claim 2 , wherein the chamber is formed from one of a bladder or a bellows.
4. The device of claim 3 , wherein the deflection of the portion of the electroactive polymer squeezes the bladder or bellows to reduce a volume of the bladder or the bellows.
5. The device of claim 3 , wherein the deflection of the portion of the electroactive polymer stretches the bladder or bellows to increase a volume of the bladder or the bellows.
6. The device of claim 3 , wherein the chamber is formed from a cylinder and a piston wherein the one surface is a portion of a piston head.
7. The device of claim 2 , wherein the deflection of the portion of the electroactive polymer causes a change in a volume of the chamber.
8. The device of claim 7 , wherein the change in the volume in the chamber compresses the fluid.
9. The device of claim 7 , wherein the change in the volume in the chamber expands the fluid.
10. The device of claim 7 , wherein the change in the volume in the chamber causes a thermodynamic phase change in at least a portion of the fluid.
11. The device of claim 7 , wherein the change in volume in the chamber draws fluid into the chamber.
12. The device of claim 7 , wherein the change in volume in the chamber expels fluid from the chamber.