Waste heat recovery system

Patent metadata

Field	Value
Publication number	US-9845711-B2
Application number	US-201313902719-A
Country	US
Kind code	B2
Filing date	May 24, 2013
Priority date	May 24, 2013
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

A waste heat recovery system includes a Rankine cycle (RC) circuit having a pump, a boiler, an energy converter, and a condenser fluidly coupled via conduits in that order, to provide additional work. The additional work is fed to an input of a gearbox assembly including a capacity for oil by mechanically coupling to the energy converter to a gear assembly. An interface is positioned between the RC circuit and the gearbox assembly to partially restrict movement of oil present in the gear assembly into the RC circuit and partially restrict movement of working fluid present in the RC circuit into the gear assembly. An oil return line is fluidly connected to at least one of the conduits fluidly coupling the RC components to one another and is operable to return to the gear assembly oil that has moved across the interface from the gear assembly to the RC circuit.

First claim

What is claimed is:

1. A waste heat recovery system configured to be operatively coupled to an internal combustion engine, the waste heat recovery system comprising:
a Rankine cycle (RC) circuit operable to convert heat energy of the internal combustion engine, said RC circuit including a pump, a boiler, an energy converter, a condenser, and a conduit fluidly connecting the energy converter and the condenser;
a gear assembly mechanically coupled to the energy converter, said gear assembly including a capacity for oil;
an interface positioned between the RC circuit and the gear assembly; and
an oil collector positioned in the conduit between the energy converter and the condenser, wherein the waste heat recovery system is structured to return, due to a first pressure of oil proximate the oil collector being higher than a second pressure of oil proximate the gear assembly due to a dynamic pressure of the oil proximate the oil collector, oil that has moved across the interface from the gear assembly to the RC circuit.

2. The waste heat recovery system according to claim 1 , wherein the oil collector comprises:
a port in an interior of the conduit between the energy converter and the condenser; and
a channel formed in an inner wall of the conduit and having one end distal to the port and another end proximal to the port.

3. The waste heat recovery system according to claim 1 , further comprising an oil return line fluidly connected to the oil collector and operable to return to the gear assembly oil that has moved across the interface from the gear assembly to the RC circuit.

4. The waste heat recovery system according to claim 3 , further comprising:
a flow control device positioned in a path of the oil return line;
a sensor adapted to sense a characteristic of the waste heat recovery system and generate a signal indicative of the sensed characteristic; and
a controller to cause the flow control device to open based on a comparison of the generated signal with a predetermined condition.

5. The waste heat recovery system according to claim 4 , wherein the predetermined condition is at least one of a threshold value corresponding to a sensed pressure at an inlet of the energy converter, a threshold value corresponding to a sensed temperature at the inlet of the energy converter, a threshold value corresponding to an oil temperature, whether presence of oil is detected, and a threshold value corresponding to sensed time spent at a particular engine operating condition.

6. The waste heat recovery system according to claim 1 , wherein the gear assembly includes an input shaft mechanically coupled to the energy converter and the interface is a seal for the input shaft.

7. The waste heat recovery system according to claim 1 , further comprising:
a vent positioned at the gear assembly;
a working fluid vapor return line fluidly connected between the vent and the conduit fluidly connecting the energy converter to the condenser; and
a check valve in the working fluid vapor return line configured to prevent back flow of working fluid vapor into the gear assembly from the conduit fluidly connecting the energy converter to the condenser.

8. A waste heat recovery system, comprising:
a Rankine cycle (RC) circuit operable to convert heat energy of a waste heat source, said RC circuit including a boiler fluidly connected to a pump downstream of the pump, an energy converter fluidly connected to the boiler downstream of the boiler, a condenser fluidly connected to the energy converter downstream of the energy converter and fluidly connected to the pump upstream of the pump, each fluid connection between the boiler, pump, energy converter and condenser comprising a conduit;
a gear assembly mechanically coupled to the energy converter, said gear assembly including a capacity for oil;
an interface positioned between the RC circuit and the gear assembly;
an oil collector positioned in the conduit between the energy converter and the condenser; and
an oil return line fluidly connected to the oil collector and operable to return to the gear assembly, due to a first pressure of oil proximate the oil collector being higher than a second pressure of oil proximate the gear assembly due to a dynamic pressure of the oil proximate the oil collector, oil that has moved across the interface from the gear assembly to the RC circuit.

9. The waste heat recovery system according to claim 8 , wherein the gear assembly includes an input shaft mechanically coupled to the energy converter and the interface is a seal for the input shaft.

10. The waste heat recovery system according to claim 8 , wherein the oil collector is positioned proximate a bend in the conduit between the energy converter and the condenser.

11. The waste heat recovery system according to claim 8 , wherein the oil collector comprises:
a port providing a passageway between an interior of the conduit between the energy converter and the condenser; and
a channel formed in an inner wall of the conduit configured to flow the working fluid and having one end distal to the port and another end proximal to the port;
wherein the oil return line is fluidly connected between the oil collector and the gear assembly.

12. The waste heat recovery system according to claim 8 , wherein the oil collector comprises a channel structure comprising at least one channel that extends along a path that intersects a tangential fluid flow path in the conduit between the energy converter and the condenser, the at least one channel configured to collect and guide oil on an inner wall of the conduit through an opening of the oil collector.

13. The waste heat recovery system according to claim 12 , wherein the at least one channel is at least two channels.

14. The waste heat recovery system according to claim 8 , further comprising:
a flow control device positioned in the path of the oil return line;
a sensor adapted to sense a characteristic of the waste heat recovery system and generate a signal indicative of the sensed characteristic; and
a controller operable to cause the flow control device to open based on a comparison of the generated signal with a predetermined condition.

15. The waste heat recovery system according to claim 14 , wherein the predetermined condition is at least one of a threshold value corresponding to a sensed pressure at an inlet of the energy converter, a threshold value corresponding to a sensed temperature at the inlet of the energy converter, a threshold value corresponding to an oil temperature, whether presence of oil is detected, and a threshold value corresponding to sensed time spent at a particular engine operating condition.

16. The waste heat recovery system according to claim 8 , further comprising:
a flow control device positioned in the oil return line and operable to control an amount of oil flow in the oil return line;
a sensor adapted to sense a characteristic of the waste heat recovery system and generate a signal indicative of the sensed characteristic; and
a controller operable to cause the flow control device to open based on a comparison of the generated signal with a predetermined condition.

17. The waste heat recovery system according to claim 16 , wherein the predetermined condition is at least one of a threshold value corresponding to a sensed pressure at an inlet of the energy converter, a threshold value corresponding to a sensed temperature at the inlet of the energy converter, a threshold value corresponding to a sensed oil temperature, whether presence of oil is detected, a threshold value corre

Assignees

• Cummins Inc
• Paccar Inc

Inventors

• Ernst Timothy C
• Zigan James A

Classifications

• F01K9/00 Primary

  Plants characterised by condensers arranged or modified to co-operate with the engines (by condensers structurally combined with engines F01K11/00; steam condensers per se F28B)(F01K23/04 takes precedence) · CPC title

• F01K25/04 Primary

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

• F01K25/06

  using mixtures of different fluids (plants using mixtures of steam and gas F01K21/04) · CPC title