Mechanically pumped system for direct control of two-phase isothermal evaporation

Patent metadata

Field	Value
Publication number	US-10906150-B2
Application number	US-201916380644-A
Country	US
Kind code	B2
Filing date	Apr 10, 2019
Priority date	Apr 11, 2018
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

A thermal system may comprise a reservoir, a first fluid flowpath, and a second fluid flowpath. The first fluid flowpath may start at the reservoir and return to the reservoir. The first fluid flowpath may comprise, in a direction of the fluid flow, a first side of a sub-cooler, a liquid pump, a first side of a pre-heater, and a first side of an evaporator. The second fluid flowpath may start at the reservoir and return to the reservoir. The second fluid flowpath may comprise, in a direction of a fluid flow, a pressure regulator, a vapor compressor, a first side of a condenser, and an expansion value.

First claim

What is claimed is:

1. A thermal system comprising:
a reservoir;
a first fluid flowpath from the reservoir and returning to the reservoir comprising in a direction of fluid flow:
a first side of a sub-cooler;
a liquid pump;
a first side of a pre-heater; and
a first side of an evaporator

and
a second fluid flowpath from the reservoir and returning to the reservoir comprising in a direction of fluid flow:
a pressure regulator;
a vapor compressor;
a first side of a condenser; and
an expansion valve.

2. The thermal system of claim 1 , wherein said first fluid flowpath further comprises a pressure regulator after said first side of said evaporator.

3. The thermal system of claim 1 further comprising a sub-cooling fluid flowpath from the reservoir to a suction of the vapor compressor comprising in a direction of fluid flow:
a flow controller; and
a second side of the sub-cooler.

4. The thermal system of claim 3 further comprising a pre-heating fluid flowpath from a discharge of the vapor compressor to the reservoir comprising in a direction of fluid flow:
a flow controller; and
a second side of the pre-heater.

5. The thermal system of claim 3 further comprising a pre-heating fluid flowpath from the discharge of the vapor compressor to the reservoir comprising in a direction of fluid flow:
a second side of the pre-heater; and
a flow controller.

6. The thermal system of claim 1 further comprising a pre-heating fluid flowpath from a discharge of the vapor compressor to the reservoir comprising in a direction of fluid flow:
a flow controller; and
a second side of the pre-heater.

7. The thermal system of claim 1 further comprising a pre-heating fluid flowpath from a discharge of the vapor compressor to the reservoir comprising in a direction of fluid flow:
a second side of the pre-heater; and
a flow controller.

8. The thermal system of claim 1 comprising a fluid in said first and second fluid flowpaths, wherein said fluid is a sub-cooled liquid at a suction of the liquid pump by a first margin of sub-cooling and the fluid is a sub-cooled liquid at an inlet to the evaporator by a second margin of sub-cooling.

9. The thermal system of claim 8 wherein the fluid at an outlet of the evaporator has a vapor quality no more than 90%.

10. The thermal system of claim 9 wherein a temperature of the fluid at an inlet of an evaporator channel is the same as a temperature of the fluid at an outlet of the evaporator channel.

11. The thermal system of claim 8 wherein a temperature of the fluid at an inlet of an evaporator channel is the same as a temperature of the fluid at an outlet of the evaporator channel.

12. The thermal system of claim 1 further comprising a cooling fluid flowpath from the reservoir to a suction of the vapor compressor comprising in a direction of fluid flow:
a control valve; and
a heat exchanger.

13. The thermal system of claim 1 wherein a fluid at an outlet of the evaporator has a vapor quality no more than 90%.

14. A thermal system for maintaining the temperature of a primary heat load, said thermal system comprising:
a reservoir;
a cooling loop originating from the reservoir and returning to the reservoir, the cooling loop comprising:
a primary heat exchanger having a cooling fluid outlet in fluid communication with the reservoir;
a liquid pump having a suction in fluid communication with the reservoir and a discharge in fluid communication with a cooling fluid inlet to the primary heat exchanger;
a sub-cooler between the reservoir and the suction of the pump;
a pre-heater between the discharge of the pump and the cooling fluid inlet to the primary heat exchanger; and
a pressure regulator between the primary heat exchanger and the reservoir; and

a heat rejection loop originating from the reservoir and returning the reservoir, the heat rejection loop comprising;
a condenser having a hot fluid outlet in fluid communication with the reservoir;
a vapor compressor having a suction in fluid communication with the reservoir and a discharge in fluid communication with a hot fluid inlet of the condenser;
a pressure regulator between the reservoir and the suction of the vapor compressor; and
an expansion valve between a fluid outlet of the condenser and the reservoir.

15. The thermal system of claim 14 wherein a heat sink for the sub-cooler comprises fluid drawn from the reservoir.

16. The thermal system of claim 15 wherein a heat source for the pre-heater comprises fluid drawn from the discharge of the vapor compressor.

17. The thermal system of claim 14 further comprising a secondary cooling flowpath originating from the reservoir and discharging into the suction of the vapor compressor, the secondary cooling flowpath comprising a flow control valve and the cold side of a secondary heat exchanger.

18. A method of maintaining the temperature of a primary heat load comprising:
drawing a fluid from a reservoir;
sub-cooling the fluid drawn from the reservoir;
pumping the sub-cooled fluid to an inlet of an evaporator;
pre-heating the pumped fluid prior to the inlet of the evaporator to a predetermined margin of sub-cooling;
evaporating a portion of the fluid in the evaporator;
regulating the pressure of the fluid at the outlet of the evaporator to thereby maintain a substantially constant fluid temperature between the inlet and the outlet of the evaporator; and
returning the partially evaporated fluid to the reservoir;
while simultaneously:
drawing fluid from the reservoir;
regulating the pressure of the fluid drawn from the reservoir;
compressing the fluid drawn from the reservoir;
condensing the compressed fluid;
expanding the condensed fluid; and
returning the expanded fluid to the reservoir.

19. The method of claim 18 comprising sub-cooling the fluid drawn from the reservoir by transferring heat from the fluid to expanded fluid drawn from the reservoir.

20. The method of claim 19 comprising pre-heating the fluid prior to the inlet of the evaporator by transferring heat from fluid drawn from compressed fluid.

21. The method of claim 18 comprising pre-heating the fluid prior to the inlet of the evaporator by transferring heat from fluid drawn from compressed fluid.

Assignees

• Rolls Royce Nam Tech Inc

Inventors

• Jansen Eugene
• Donovan Eric

Classifications

• F25B40/00 Primary

  Subcoolers, desuperheaters or superheaters · CPC title

• F25B25/005

  using primary and secondary systems · CPC title

• F25B41/00

  Fluid-circulation arrangements · CPC title

• F25B2400/23

  Separators · CPC title

• B23Q11/141 Primary

  using a closed fluid circuit for cooling or heating · CPC title