Working fluid for a device, device and method for converting heat into mechanical energy

Patent metadata

Field	Value
Publication number	US-9739179-B2
Application number	US-201514657567-A
Country	US
Kind code	B2
Filing date	Mar 13, 2015
Priority date	Mar 13, 2015
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

A working fluid ( 6 ) for a device ( 4 ) for converting heat into mechanical energy is disclosed. The working fluid ( 6 ) comprises a fluid ( 7 ) having a boiling temperature in the range between 30 and 250° C. at a pressure of 1 bar and nanoparticles ( 8 ) which are dispersed or suspended in the liquid phase of the fluid ( 7 ). Said nanoparticles ( 8 ) are instrumented as condensation and/or boiling nuclei and the surface of said nanoparticles ( 8 ) is adapted to support condensation and/or boiling.

First claim

The invention claimed is:

1. A device for converting heat into mechanical energy comprising:
a working fluid comprising:
a fluid having a boiling temperature in the range between 30 and 250° C. at a pressure of 1 bar: and
nanoparticles which are dispersed or suspended in the liquid phase of the fluid; wherein said nanoparticles are instrumented as condensation and/or boiling nuclei and wherein the surface of said nanoparticles is adapted to support condensation and/or boiling;
an inflow condenser device adapted for at least partly condensing the working fluid thereby removing heat from the working fluid, the inflow condenser device comprising a plurality of stator heat exchangers which are arranged in series with respect to a flow direction of the working fluid for removing heat from the working fluid; and
a rotor arranged between two stator heat exchangers of the inflow condenser device with respect to the flow direction of the working fluid so that a liquid-gas mixture of the working fluid at least partially converts an internal and/or kinetic energy of the liquid-gas mixture of the working fluid into mechanical energy associated with the rotor;
wherein said nanoparticles contained in the working fluid are adapted to increase an overall condensation surface for enhancing and accelerating a condensation process and wherein the condensation process is implemented such that a fraction of the liquid-gas mixture of the working fluid condenses at said nanoparticles.

2. The device of claim 1 , further comprising
a boiler adapted to heat the working fluid for generating the liquid-gas mixture of the working fluid; and
a turbine adapted to expand the liquid-gas mixture of the working fluid.

3. The device of claim 1 , wherein the liquid-gas mixture of the working fluid enters the inflow condenser device with a vapor quality between 100% and 80% or between 99% and 93% and/or wherein the liquid-gas mixture of the working fluid leaves the inflow condenser device with a vapor quality between 60% and 40% or between 55% and 45%.

4. The device of claim 2 , wherein the boiler is a channel flow boiler having at least one channel, said channel flow boiler heating the working fluid for generating the liquid-gas mixture of the working fluid and wherein said nanoparticles act as nucleation sites for boiling within the at least one channel.

5. A method for converting heat into mechanical energy, wherein the method comprises:
heating (S 1 ) a working fluid comprising nanoparticles for generating a liquid-gas mixture of the working fluid;
expanding (S 2 ) the liquid-gas mixture of the working fluid;
converting (S 3 ) the internal and/or kinetic energy of the liquid-gas mixture of the working fluid into mechanical energy; and
at least partly condensing (S 4 ) the liquid-gas mixture of the working fluid in an inflow condenser device such that condensation at least partly sets in at said nanoparticles as condensation nuclei;
wherein said inflow condenser device comprises a plurality of stator heat exchangers which are arranged in series with respect to a flow direction of the working fluid for removing heat from the working fluid; and
wherein a rotor is arranged between two stator heat exchangers of the inflow condenser device with respect to the flow direction of the working fluid so that the liquid-gas mixture of the working fluid at least partially converts an internal and/or kinetic energy of the liquid-gas mixture of the working fluid into mechanical energy associated with the rotor; and
wherein the method is operated as a thermodynamic cycle and/or the condensation in the inflow condenser device is approximately isothermal.

6. The method of claim 5 , wherein the plurality of stator heat exchangers enable a cyclic re-cooling during the condensation in the inflow condenser device to allow an isothermal condensation.

7. The device of claim 1 , wherein a diameter of said nanoparticles in said working fluid is between 1 and 100 nm.

8. The device of claim 1 , wherein a concentration of said nanoparticles in the working fluid is in the range of 0.01 to 1 percent by volume.

9. The device of claim 1 , wherein said nanoparticles have a functionalized surface.

10. The device of claim 1 , wherein said nanoparticles comprise an oxide monolayer and/or an organic monolayer.

11. The device of claim 1 , wherein a diameter of said nanoparticles in said working fluid is between 1 and 50 nm.

12. The device of claim 1 , wherein a diameter of said nanoparticles in said working fluid is between 1 and 10 nm.

13. The device of claim 1 , wherein a concentration of said nanoparticles in the fluid is in the range of 0.05 to 0.5 percent by volume.

14. The device of claim 1 , wherein a concentration of said nanoparticles in the fluid is in the range of 0.06 to 0.14 percent by volume.

15. The device of claim 1 , wherein said nanoparticles have a hydrophilic surface.

Assignees

• IBM

Inventors

• Burg Brian
• Michel Bruno
• Paredes Stephan

Classifications

• F01K25/04

  the fluid being in different phases, e.g. foamed · CPC title

• F01K11/02 Primary

  the engines being turbines · CPC title

• F01K27/00 Primary

  Plants for converting heat or fluid energy into mechanical energy, not otherwise provided for · CPC title

• F01K25/08

  using special vapours · CPC title

• C09K5/048 Primary

  Boiling liquids as heat transfer materials · CPC title