AC induction field heating of graphite foam

Patent metadata

Field	Value
Publication number	US-9739501-B2
Application number	US-201414466532-A
Country	US
Kind code	B2
Filing date	Aug 22, 2014
Priority date	Aug 22, 2014
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

A magneto-energy apparatus includes an electromagnetic field source for generating a time-varying electromagnetic field. A graphite foam conductor is disposed within the electromagnetic field. The graphite foam when exposed to the time-varying electromagnetic field conducts an induced electric current, the electric current heating the graphite foam. An energy conversion device utilizes heat energy from the heated graphite foam to perform a heat energy consuming function. A device for heating a fluid and a method of converting energy are also disclosed.

First claim

We claim:

1. A magneto-energy apparatus for heating a fluid, comprising:
an electromagnetic field generating device for generating a time-varying electromagnetic field of between 180 kHz and 10 MHz;
a porous graphite foam conductor disposed within the electromagnetic field, the porous graphite foam conductor comprising a plurality of pores including subsurface portions that are interconnected so as to permit fluid flow there through, the pores defined by pore walls having a wall thickness of from 50 μm to 100 μm and the porous graphite foam conductor having a porosity of from 67% to 89%;
the porous graphite foam conductor when exposed to the time-varying electromagnetic field conducting an induced electric current, the electric current heating the porous graphite foam conductor;
an energy conversion device utilizing heat energy from the porous graphite foam conductor to perform a heat energy consuming function on the fluid, by contacting the fluid to the porous graphite foam conductor including subsurface pore wall portions of the porous graphite foam conductor; and,
a feedback control for controlling the electromagnetic field generating device according to a sensed characteristic of the fluid.

2. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has a thermal conductivity of at least 40 W/mK.

3. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has a thermal conductivity of between 40 W/mK and 100 W/mK.

4. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has a porosity of at least 75%.

5. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has a thermal conductivity of at least 220 W/mK.

6. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has a thermal conductivity of between 220 W/mK and 240 W/mK.

7. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has a porosity of at least 69%.

8. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has a porosity of between 69% to 85%.

9. The magneto-energy apparatus of claim 1 , wherein the specific thermal conductivity of the porous graphite foam conductor is at least 109 W cm 3 /mKg.

10. The magneto-energy apparatus of claim 1 , wherein the specific thermal conductivity of the porous graphite foam conductor is between 109 W cm 3 /mKg and 200 W cm 3 /mKg.

11. The magneto-energy apparatus of claim 1 , wherein the time varying electromagnetic field has a frequency of between 25 kHz and 1 MHz.

12. The magneto-energy apparatus of claim 1 , wherein the time varying electromagnetic field has a power of at least 1 kW.

13. The magneto-energy apparatus of claim 1 , wherein the time varying electromagnetic field has a power of between 10 W and 20 kW.

14. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor is derived from a pitch selected from the group consisting of petroleum-derived mesophase pitch, petroleum derived isotropic pitch, coal-tar-derived mesophase pitch, synthetic mesophase pitch, and synthetic isotropic pitch.

15. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has an X-ray diffraction pattern as depicted in FIG. 26 .

16. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has a specific thermal conductivity greater than four times that of copper.

17. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor has an X-ray diffraction pattern exhibiting doublet peaks at 2θ angles between 40 degrees and 50 degrees.

18. The magneto-energy apparatus of claim 1 , wherein the energy conversion device is a water heater.

19. The magneto-energy apparatus of claim 1 , wherein the porous graphite foam conductor is within an electrically non-conductive housing.

20. The magneto-energy apparatus of claim 1 , wherein the fluid flows through a fluid flow path, and the graphite foam conductor is positioned in the fluid flow path such that all of the flowing fluid flows through the interconnected pores the graphite foam conductor.

21. A device for heating a fluid, comprising:
an electromagnetic field generating device for generating a time-varying electromagnetic field of between 180 kHz and 10 MHz;
a porous graphite foam conductor disposed within the electromagnetic field, the porous graphite foam conductor comprising a plurality of pores including subsurface portions that are interconnected so as to permit fluid flow there through, the pores defined by pore walls having a wall thickness of from 50 μm to 100 μm and the porous graphite foam conductor having a porosity of from 67% to 89%, the porous graphite foam conductor when exposed to the time-varying electromagnetic field conducting an induced electric current, the electric current heating the porous graphite foam conductor including subsurface pore wall portions;
at least one fluid flow path for contacting the fluid with the porous graphite foam conductor including subsurface pore wall portions of the porous graphite foam conductor, whereby the porous graphite foam conductor will transfer heat to the fluid; and
a feedback control for controlling the electromagnetic field generating device according to a sensed characteristic of the fluid.

22. The device of claim 21 , wherein the fluid is water.

23. The device of claim 21 , further comprising a switch for selectively energizing the electromagnetic field source.

24. The device of claim 21 , further comprising at least one temperature sensor, the temperature sensor operating to turn on the electromagnetic field source when the temperature of the fluid is below a set point, and to turn off the electromagnetic field source when the temperature of the fluid is above a set point.

25. The device of claim 21 , wherein the fluid flows through a fluid flow path, and the graphite foam conductor is positioned in the fluid flow path such that all of the flowing fluid flows through the interconnected pores the graphite foam conductor.

26. A method of converting energy and imparting at least a portion of that energy to a fluid, comprising the steps of:
providing an electromagnetic field generating device for generating a time-varying electromagnetic field of between 180 kHz and 10 MHz;
providing a porous graphite foam conductor disposed within the electromagnetic field, the porous graphite foam conductor comprising a plurality of pores including subsurface portions that are interconnected so as to permit fluid flow there through, the pores defined by pore walls having a wall thickness of from 50 μm to 100 μm and the porous graphite foam conductor having a porosity of from 67% to 89%, the porous graphite foam conductor when exposed to the time-varying electromagnetic field conducting an induced electric current, the electric current heating the porous graphite foam conductor including subsurface pore wall portions;
providing an energy conversion device and utilizing heat energy from the heated porous graphite foam conductor to perform a heat energy consuming function on the fluid by contacting the fluid to the porous graphite foam conductor including subsurface pore wall portions of the porous graphite foam conductor; and,
providing feedback control for controlling the electromagnetic field generating device accor

Assignees

• Ut Battelle Llc

Inventors

• Klett James W
• Rios Orlando
• Kisner Roger

Classifications

• F24H1/0018 Primary

  using electric energy supply · CPC title

• H05B6/105

  using a susceptor · CPC title