# US 11,028,735 B2 · Thermal power cycle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,735 B2 - Document ID: US11028735B2 - Status: Granted - Kind: B2 - Application number: 13/816,490 - Filed: 2011-08-26 - Published: 2013-05-30 - Granted: 2021-06-08 - Earliest claimed: 2010-08-26 - Applicants: Michael Joseph Timlin, III - Inventors: Michael Joseph Timlin, III - Web page: https://patentgrep.com/patent/US11028735B2 ## CPC - F01K 25/08: using special vapours - C09K 5/041: {for compression-type refrigeration systems} - F01K 25/06: using mixtures of different fluids (plants using mixtures of steam and gas F01K21/04) - C09K 2205/102: Alcohols - 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) - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract One embodiment of an improved thermal power cycle comprising a wet binary motive fluid, pump (21), evaporator (22), expander (23), and condenser (24). Using a binary motive fluid, it can operate efficiently over a lower range of heat source temperatures than the steam Rankine cycle. Using a wet binary motive fluid, it eliminates the need for superheating the fluid in evaporator (22), allows for complete expansion of the fluid in expander (23), and reduces back-pressure by the fluid on expander (23), thereby providing higher efficiency than the ORC (organic Rankine cycle), Eliminating the regenerator that is used by ORC systems results in a simpler, less costly system. Using direct-contact heat exchange in condenser (24) rather than the indirect-contact heat exchange used by ORC systems results in more efficient condensation of the fluid. Using a pump (21) rather than the power-hungry compressor used by ORC systems further reduces power losses and expenses. Accordingly, the improved cycle provides higher overall system efficiency at lower overall system cost. Other embodiments are described and shown. ## Claims ### Claim 1 A method for converting heat into mechanical power comprising: (a) compressing a motive fluid to form a subcooled liquid, the motive fluid being a non-aqueous wet fluid; (b) evaporating a first portion of the subcooled liquid with the heat at subcritical conditions to form a vapor; (c) expanding the vapor to produce mechanical power and a two-phase vapor and liquid mixture, the vapor being expanded approximately isentropically; (d) combining a second portion of the subcooled liquid with the two-phase vapor and liquid mixture to form a combined mixture; (e) condensing the combined mixture to form the motive fluid in step (a); repeating steps (a)-(e); and producing the mechanical power; wherein the motive fluid is an azeotrope. ### Claim 2 (depends on 1) The method of claim 1 wherein the boiling point of the motive fluid at standard atmospheric pressure is no more than 100° C. ### Claim 3 (depends on 1) The method of claim 1 wherein the motive fluid comprises methanol. ### Claim 4 (depends on 1) The method of claim 1 wherein the motive fluid includes a mixture of at least two substances. ### Claim 5 (depends on 1) The method of claim 1 wherein the first portion of the subcooled liquid is evaporated by a heat source having a temperature of no more than 200° C. ### Claim 6 (depends on 1) The method of claim 1 wherein the two-phase vapor and liquid mixture in step (c) is a first two-phase vapor and liquid mixture and wherein step (c) further comprises: reheating the first two-phase vapor and liquid mixture to produce a reheated fluid; and expanding the reheated fluid to produce a second two-phase vapor and liquid mixture; and wherein the two-phase vapor and liquid mixture in step (d) is the second two-phase vapor and liquid mixture. ### Claim 7 (depends on 1) The method of claim 1 wherein the vapor formed by evaporating the subcooled liquid is superheated vapor. ### Claim 8 (depends on 1) The method of claim 1 comprising expanding the vapor in a reaction turbine. ### Claim 9 (depends on 8) The method of claim 8 wherein the reaction turbine is an axial-flow, reaction turbine. ### Claim 10 (depends on 1) The method of claim 1 wherein the subcooled liquid is evaporated in an evaporator, the vapor is expanded in an expander, and the combined mixture is condensed in a condenser. ### Claim 11 A method for converting heat into mechanical power comprising: (a) compressing a motive fluid to form a subcooled liquid, the motive fluid being a non-aqueous wet fluid; (b) evaporating a first portion of the subcooled liquid with the heat at subcritical conditions to forma saturated motive fluid, the saturated motive fluid being substantially saturated vapor with no superheat; (c) expanding the saturated motive fluid to produce mechanical power and a two-phase vapor and liquid mixture, the saturated motive fluid being expanded approximately isentropically; (d) combining a second portion of the subcooled liquid with the two-phase vapor and liquid mixture to form a combined mixture; (e) condensing the combined mixture to form the motive fluid in step (a); repeating steps (a)-(e); and producing the mechanical power; wherein the motive fluid is an azeotrope. ### Claim 12 (depends on 11) The method of claim 11 wherein the boiling point of the motive fluid at standard atmospheric pressure is no more than 100° C. ### Claim 13 (depends on 11) The method of claim 11 wherein the motive fluid comprises methanol. ### Claim 14 (depends on 11) The method of claim 11 wherein the motive fluid includes a mixture of at least two substances. ### Claim 15 (depends on 11) The method of claim 11 wherein the two-phase vapor and liquid mixture in step (c) is a first two-phase vapor and liquid mixture and wherein step (c) further comprises: reheating the first two-phase vapor and liquid mixture to produce a reheated fluid; and expanding the reheated fluid to produce a second two-phase vapor and liquid mixture; and wherein the two-phase vapor and liquid mixture in step (d) is the second two-phase vapor and liquid mixture. ### Claim 16 (depends on 11) The method of claim 11 comprising expanding the saturated motive fluid in a reaction turbine. ### Claim 17 (depends on 16) The method of claim 16 wherein the reaction turbine is an axial-flow, reaction turbine. ### Claim 18 (depends on 11) The method of claim 11 wherein the subcooled liquid is evaporated in an evaporator, the saturated motive fluid is expanded in an expander, and the combined mixture is condensed in a condenser. ### Claim 19 (depends on 18) The method of claim 18 wherein the motive fluid is compressed by a pump, and wherein the motive fluid moves from the condenser to the pump without passing through a fluid reservoir.