# US 8,739,541 B2 · System and method for cooling an expander > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,739,541 B2 - Document ID: US8739541B2 - Status: Granted - Kind: B2 - Application number: 12/892,973 - Filed: 2010-09-29 - Published: 2012-03-29 - Granted: 2014-06-03 - Earliest claimed: 2010-09-29 - Assignees: General Electric Company - Applicants: Gabor Ast; Sebastian Walter Freund; Thomas Johannes Frey; Pierre Sebastien Huck; Herbert Kopecek; Günther Wall - Inventors: Gabor Ast; Sebastian Walter Freund; Thomas Johannes Frey; Pierre Sebastien Huck; Herbert Kopecek; Günther Wall - Web page: https://patentgrep.com/patent/US8739541B2 ## CPC - F01K 25/10: the vapours being cold, e.g. ammonia, carbon dioxide, ether - F01K 13/00: General layout or general methods of operation of complete plants - F01K 23/065: {the combustion taking place in an internal combustion piston engine, e.g. a diesel engine} - F01K: STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES (gas-turbine or jet-propulsion plants F02; nuclear power plants, engine arrangements therein G21D) ## Abstract A Rankine cycle system includes: an evaporator configured to receive heat from a heat source and circulate a working fluid to remove heat from the heat source; an expander in flow communication with the evaporator and configured to expand the working fluid fed from the evaporator; a condenser in flow communication with the expander and configured to condense the working fluid fed from the expander; a pump in flow communication with the condenser and configured to pump the working fluid fed from the condenser; a first conduit for feeding a first portion of the working fluid from the pump to the evaporator; and a second conduit for feeding a second portion of the working fluid from the pump to the expander. ## Claims ### Claim 1 A Rankine cycle system, comprising: an evaporator configured to receive heat from a heat source and circulate a working fluid to remove heat from the heat source; an expander in flow communication with the evaporator and configured to expand the working fluid fed from the evaporator; a condenser in flow communication with the expander and configured to condense the working fluid fed from the expander; a pump in flow communication with the condenser and configured to pump the working fluid fed from the condenser, a first conduit for feeding a first portion of the working fluid from the pump to the evaporator; and a second conduit for feeding a second portion of the working fluid from the pump directly to the expander, wherein the second portion of the working fluid is fed to at least one location in the expander, and wherein the expander comprises a multi-stage expander and the at least one location comprises a location in-between two stages of the multi-stage expander. ### Claim 2 (depends on 1) The system of claim 1, wherein the working fluid comprises an organic working fluid. ### Claim 3 (depends on 2) The system of claim 2, wherein the expander comprises expander components, and wherein the second portion of the working fluid is fed to the expander to cool at least one of the expander components. ### Claim 4 (depends on 3) The system of claim 3, wherein the expander components comprise a casing, a bearing, a shaft, and an impeller, and wherein the bearing, the shaft, and the impeller are disposed in the casing. ### Claim 5 (depends on 4) The system of claim 4, further comprising a coupling device, wherein the second conduit is coupled to the expander via the coupling device. ### Claim 6 (depends on 4) The system of claim 4, further comprising a regulating device configured to control the flow of the second portion of the working fluid fed to the expander. ### Claim 7 (depends on 6) The system of claim 6, wherein the regulating device is configured to control the flow of the second portion of the working fluid fed to the expander based on a temperature of at least one of the expander components. ### Claim 8 (depends on 7) The system of claims 7, further comprising a temperature sensor for obtaining the temperature of the at least one of the expander components. ### Claim 9 (depends on 1) The system of claim 1, wherein the second portion of the condensed working fluid comprises 0.3% to 1% of a mass flow of the working fluid circulated in the Rankine cycle system. ### Claim 10 A Rankine cycle system, comprising: an evaporator configured to receive heat from a heat source and circulate a working fluid to remove heat from the heat source; an expander in flow communication with the evaporator and configured to expand the working fluid fed from the evaporator; a condenser in flow communication with the expander and configured to condense the working fluid fed from the expander; a pump in flow communication with the condenser and configured to pump the working fluid fed from the condenser, a first conduit for feeding a first portion of the working fluid from the pump to the evaporator; and a second conduit for feeding a second portion of the working fluid from the pump directly to the expander, wherein the second portion of the working fluid is fed to at least one location in the expander, and wherein the expander comprises a multi-stage expander and the at least one location comprises at least two locations with a first location comprising a location corresponding to a position of at least one expander component and a second location comprising a location in-between two stages of the multi-stage expander. ### Claim 11 A method of operating a Rankine cycle system, comprising circulating a working fluid in an evaporator in heat exchange relationship with a heat source so as to vaporize the working fluid; expanding the vaporized working fluid in an expander, wherein the expander comprises a multi-stage expander; condensing the expanded working fluid via a condenser fed from the expander; pumping the condensed working fluid, supplying a first portion of the pumped working fluid to the evaporator; and supplying a second portion of the pumped working fluid directly to at least one location in the expander, wherein the at least one location comprises a location in-between two stages of the multi-stage expander.