Rankine cycle system and method

Patent metadata

Field	Value
Publication number	US-9702272-B2
Application number	US-201414453160-A
Country	US
Kind code	B2
Filing date	Aug 6, 2014
Priority date	Dec 23, 2010
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

A Rankine cycle waste heat recovery system uses a receiver with a maximum liquid working fluid level lower than the minimum liquid working fluid level of a sub-cooler of the waste heat recovery system. The receiver may have a position that is physically lower than the sub-cooler's position. A valve controls transfer of fluid between several of the components in the waste heat recovery system, especially from the receiver to the sub-cooler. The system may also have an associated control module.

First claim

What is claimed is:

1. A fluid management system comprising:
a Rankine cycle waste heat recovery system, comprising:
a fluid circuit structured to circulate a working fluid;
a condenser positioned along the fluid circuit;
a sub-cooler positioned along the fluid circuit in working fluid receiving communication with the condenser and containing the working fluid in liquid form; and
a receiver positioned along the fluid circuit in working fluid receiving communication with the sub-cooler and containing the liquid working fluid, wherein a level of the liquid working fluid in the receiver is lower than a level of the liquid working fluid in the sub-cooler throughout all operating conditions.

2. The system of claim 1 , further including a pump positioned along the fluid circuit in working fluid receiving communication with the sub-cooler and connected to at least one heat exchanger, wherein the pump is operable to move the liquid working fluid in the sub-cooler to the at least one heat exchanger.

3. The system of claim 2 , wherein the at least one heat exchanger is the source of high-pressure vaporized working fluid.

4. The system of claim 2 , wherein the at least one heat exchanger receives exhaust gas from an exhaust gas recirculation system.

5. The system of claim 3 , wherein the at least one heat exchanger heats the liquid working fluid and changes the state of the liquid working fluid to the high-pressure vaporized working fluid.

6. The system of claim 5 , further comprising an energy conversion device positioned along the fluid circuit in working fluid receiving communication with the heat exchanger and operable to convert the high-pressure vaporized working fluid received from the heat exchanger to energy.

7. The system of claim 1 , wherein the receiver is physically located in a position that is lower than the sub-cooler's position.

8. The system of claim 1 , further comprising a shutoff valve positioned along the fluid circuit between the sub-cooler and the receiver.

9. The system of claim 8 , wherein the shutoff valve is closed when the fluid management system is shutdown.

10. The system of claim 8 , wherein the shutoff valve is periodically closed when the fluid management system is operational to increase levels of the working fluid in each of the sub-cooler and the condenser.

11. A fluid management system for a Rankine cycle waste heat recovery system for an internal combustion engine, the fluid management system comprising:
a fluid circuit;
a condenser positioned along the fluid circuit;
a sub-cooler fluidly connected to the condenser and containing a liquid working fluid;
a receiver fluidly connected to the sub-cooler and containing the liquid working fluid, wherein a level of the liquid working fluid in the receiver is lower than a level of the liquid working fluid in the sub-cooler throughout all operating conditions; and
a valve positioned along the fluid circuit upstream of the condenser and movable into a valve first position and a valve second position,
wherein the valve second position fluidly connects a source of high-pressure vaporized working fluid to the receiver,
wherein the high-pressure vaporized working fluid causes the liquid working fluid in the receiver to flow from the receiver to the sub-cooler, and
wherein the valve first position fluidly connects the receiver to the condenser.

12. The system of claim 11 , further comprising an energy conversion device fluidly connected to the heat exchanger and operable to convert the high-pressure vaporized working fluid received from the heat exchanger to energy.

13. The system of claim 11 , wherein the valve is a bypass valve, and further comprising a shutoff valve positioned along the fluid circuit between the sub-cooler and the receiver.

14. The system of claim 13 , wherein the shutoff valve is closed when the fluid management system is shutdown.

15. The system of claim 13 , wherein the shutoff valve is periodically closed when the fluid management system is operational to increase levels of the working fluid in each of the sub-cooler and the condenser.

16. A fluid management system for a Rankine cycle waste heat recovery system for an internal combustion engine, the fluid management system comprising:
a fluid circuit;
a condenser positioned along the fluid circuit;
a sub-cooler fluidly connected to the condenser and containing a liquid working fluid;
a receiver fluidly connected to the sub-cooler and containing the liquid working fluid, wherein a level of the liquid working fluid in the receiver is lower than a level of the liquid working fluid in the sub-cooler throughout all operating conditions; and
a valve positioned along the fluid circuit upstream of the condenser and movable into a valve first position and a valve second position,
wherein the valve second position fluidly connects a source of high-pressure vaporized working fluid to the receiver,
wherein the high-pressure vaporized working fluid causes the liquid working fluid in the receiver to flow from the receiver to the sub-cooler, and
wherein the valve includes a valve third position, the valve third position connecting the source of high-pressure vaporized working fluid to the condenser.

17. The system of claim 16 , further comprising an energy conversion device fluidly connected to the heat exchanger and operable to convert the high-pressure vaporized working fluid received from the heat exchanger to energy.

18. The system of claim 16 , wherein the valve is a bypass valve, and further comprising a shutoff valve positioned along the fluid circuit between the sub-cooler and the receiver.

19. The system of claim 18 , wherein the shutoff valve is closed when the fluid management system is shutdown.

20. The system of claim 18 , wherein the shutoff valve is periodically closed when the fluid management system is operational to increase levels of the working fluid in each of the sub-cooler and the condenser.

Assignees

• Cummins Ip Inc

Inventors

• Ernst Timothy C
• Nelson Christopher R

Classifications

• F02G5/02 Primary

  Profiting from waste heat of exhaust gases · CPC title

• F01N5/02

  the devices using heat · CPC title

• F01N2240/02

  a heat exchanger · CPC title

• F01K11/02

  the engines being turbines · CPC title

• F01K27/02 Primary

  Plants modified to use their waste heat, other than that of exhaust, e.g. engine-friction heat · CPC title