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

Patent metadata

Field	Value
Publication number	US-2016265390-A1
Application number	US-201514657567-A
Country	US
Kind code	A1
Filing date	Mar 13, 2015
Priority date	Mar 13, 2015
Publication date	Sep 15, 2016
Grant date	—

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

1 . A working fluid for a device for converting heat into mechanical energy 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.

2 . The working fluid of claim 1 , wherein a diameter of said nanoparticles is between 1 and 100 nm, preferably between 1 and 50 nm and more preferably between 1 and 10 nm.

3 . The working fluid of claim 1 , wherein a concentration of said nanoparticles in the fluid is in the range of 0.01 to 1 per cent by volume, preferably in the range of 0.05 to 0.5 per cent by volume and more preferably in the range of 0.06 to 0.14 per cent by volume.

4 . The working fluid of claim 1 , wherein said nanoparticles have a functionalized surface, in particular a hydrophilic surface.

5 . The working fluid of claim 1 , wherein said nanoparticles comprise an oxide monolayer and/or an organic monolayer.

6 . A device for converting heat into mechanical energy comprising:
a working fluid according to claim 1 ; and an inflow condenser device adapted for at least partly condensing the working fluid thereby removing heat from the working fluid; 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 a liquid-gas mixture of the working fluid condenses at said nanoparticles.

7 . The device of claim 6 , further comprising
a boiler adapted to heat the working fluid for generating the liquid-gas mixture of the working fluid; and an expansion device adapted to expand the liquid-gas mixture of the working fluid.

8 . The device of claim 6 , wherein the inflow condenser device comprises a stator heat exchanger for removing heat from the working fluid.

9 . The device of claim 8 , wherein the inflow condenser device comprises a plurality of stator heat exchangers for removing heat from the working fluid, which are arranged in series with respect to a flow direction of the working fluid.

10 . The device of claim 6 , further comprising a movable element arranged such 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 movable element.

11 . The device of claim 10 , wherein the inflow condenser device comprises a plurality of stator heat exchangers for removing heat from the working fluid, which are arranged in series with respect to a flow direction of the working fluid, and wherein the movable element is arranged between two stator heat exchangers of the inflow condenser device with respect to the flow direction of the working fluid.

12 . The device of claim 6 , wherein the liquid-gas mixture of the working fluid enters the inflow condenser device with a vapor quality between 100% and 80%, preferably 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%, preferably between 55% and 45%.

13 . The device of claim 7 , wherein the boiler is a channel flow boiler having at least one channel adapted to heat 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.

14 . 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 the method is operated as a thermodynamic cycle and/or the condensation in the inflow condenser device is approximately isothermal.

15 . The method of claim 14 , wherein a plurality of stator heat exchangers enable a cyclic re-cooling during the condensation in the inflow condenser device to allow an isothermal condensation.

Assignees

• IBM

Inventors

• Burg Brian
• Michel Bruno
• Paredes Stephan

Classifications

• F01K7/16

  the engines being only of turbine type (the engines using steam of critical or overcritical pressure F01K7/32; the engines being of extraction or non-condensing type F01K7/34) · CPC title

• F01K25/04

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

• F01K9/003

  condenser cooling circuits · CPC title

• C09K5/048 Primary

  Boiling liquids as heat transfer materials · CPC title

• F01K3/06

  the engine being of extraction or non-condensing type {(F01K3/004 takes precedence)} · CPC title