Device for controlling the working fluid circulating in a closed circuit operating according to a rankine cycle and method of using same

Patent metadata

Field	Value
Publication number	US-10458285-B2
Application number	US-77550810-A
Country	US
Kind code	B2
Filing date	May 7, 2010
Priority date	May 13, 2009
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

The present invention relates to a device for controlling the working fluid circulating in a closed circuit ( 10 ) operating according to a Rankine cycle, said circuit comprising a heat exchanger ( 22 ) for evaporation of said fluid, swept by a hot fluid (Ch) from a hot source ( 28 ), expansion means ( 30 ) for expanding the fluid in vapor form, a cooling exchanger ( 40 ) swept by a cold fluid (Fr) for condensation of the fluid in vapor form, and a circulation and compression pump ( 12 ) for the fluid in liquid form.
According to the invention, the device comprises means ( 54 ) of managing the mass of fluid contained in circuit ( 10 ).

First claim

The invention claimed is:

1. A device for controlling the working fluid circulating in a closed circuit operating according to a Rankine cycle, said circuit comprising a heat exchanger for evaporation of said working fluid, swept by a hot fluid from a hot source, expansion means with an inlet and an outlet for discharging the working fluid in vapour form, a cooling exchanger swept by a cold fluid for condensation of the working fluid in vapour form, and a fluid circulation and compression pump for the fluid in liquid form, characterized in that the device comprises a pressurized working fluid storage tank comprising a preset cap providing a preset pressure in the pressurized working fluid storage tank, the pressurized working fluid storage tank being provided outside said circuit and connected to said circuit by selective working fluid circulation means between said tank and said circuit comprising two fluid circulation lines each controlled by a throttling means, one of the fluid circulation lines connecting a zone of said tank below a level of working fluid in said tank to an inlet of said fluid circulation and compression pump and the other fluid circulation line connecting a zone of said tank below a level of working fluid in said tank to said circuit between an outlet of said fluid circulation and compression pump and said heat exchanger for evaporation of said working fluid so as to feed working fluid into said circuit or to remove working fluid from said circuit in order to obtain a desired flow rate, as well as desired pressures at said inlet and at said outlet of said expansion means, and characterized in that the working fluid in the pressurized working fluid storage tank is water in liquid form.

2. A control device as claimed in claim 1 , characterized in that said hot source comes from the exhaust gas of an internal-combustion engine.

3. A control device as claimed in claim 1 , characterized in that each of said throttling means is provided in a respective one of said two fluid circulation lines.

4. A control device as claimed in claim 1 , further comprising an engine calculator configured to control said throttling means to add working fluid to the fluid already contained in said circuit in cases where the flow rate and/or the pressure values at the inlet and outlet of the expansion means are below a desired value and to withdraw part of the working fluid present in the circuit in cases where the flow rate and/or the pressure values at the expansion means inlet and outlet are above a desired value.

5. A method of controlling the working fluid circulating in a closed circuit operating according to a Rankine cycle, said circuit comprising a heat exchanger for evaporation of said working fluid, swept by a hot fluid from a hot source, expansion means with an inlet and an outlet for discharging the working fluid in vapour form, a cooling exchanger swept by a cold fluid for condensation of the working fluid in vapour form, and a circulation and compression pump for the working fluid in liquid form, characterized in that the method comprises modifying the mass of the working fluid contained in said circuit by feeding working fluid into the circuit from a pressurized storage tank comprising a preset cap providing a preset pressure in the pressurized working fluid storage tank, the pressurized working fluid storage tank being provided outside said circuit, through a fluid circulation line connecting a zone of said storage tank below a level of working fluid in said storage tank to an inlet of said circulation and compression pump or by removing working fluid from said circuit through a fluid circulation line connecting a zone of said storage tank below a level of working fluid in said storage tank to said circuit between an outlet of said circulation and compression pump and said heat exchanger for evaporation of said working fluid so as to feed the working fluid into the pressurized storage tank in order to obtain a desired flow rate, as well as desired pressures at the inlet and at the outlet of the expansion means so as to recover the maximum amount of energy from the heat source, and characterized in that the working fluid in the pressurized tank is water in liquid form.

6. A control method as claimed in claim 5 , characterized in that the method comprises adding working fluid to the fluid already contained in said circuit in cases where the flow rate and/or the pressure values at the expansion means inlet and outlet are below said desired values.

7. A control method as claimed in claim 6 , characterized in that the method comprises adding to the working fluid already contained in said circuit a working fluid contained in a storage tank.

8. A control method as claimed in claim 5 , characterized in that the method comprises withdrawing part of the working fluid present in the circuit in cases where the flow rate and/or the pressure values at the expansion means inlet and outlet are above the desired values.

9. A control method as claimed in claim 5 , characterized in that the heat exchanger for evaporation of said working fluid is swept by exhaust gas of an internal-combustion engine.

10. A control method as claimed in claim 5 , characterized in that feeding working fluid into the circuit from a pressurized storage tank provided outside said circuit to an inlet of said circulation and compression pump comprises feeding liquid working fluid into the circuit from a pressurized storage tank provided outside said circuit to an inlet of said circulation and compression pump.

11. A device for controlling the working fluid circulating in a closed circuit operating according to a Rankine cycle, the closed circuit comprising a heat exchanger for evaporation of the working fluid, swept by a hot fluid from a hot source, a pressure regulator having an inlet and an outlet for discharging the working fluid in vapour form, a cooling exchanger swept by a cold fluid for condensation of the working fluid in vapour form, and a fluid circulation and compression pump for the fluid in liquid form, characterized in that the device comprises a pressurized working fluid storage tank comprising a preset cap providing a preset pressure in the pressurized working fluid storage tank, the pressurized working fluid storage tank being provided outside the closed circuit and connected to the closed circuit by a first fluid circulation line connecting a zone of the pressurized working fluid storage tank below a level of working fluid in the pressurized working fluid storage tank to an inlet of the fluid circulation and compression pump, a first valve to control flow of working fluid through the first fluid circulation line to selectively feed working fluid into the closed circuit in order to obtain a desired flow rate, a second fluid circulation line connecting a zone of the pressurized working fluid storage tank below a level of working fluid in the pressurized working fluid storage tank to the closed circuit between an outlet of the fluid circulation and compression pump and the heat exchanger for evaporation of the working fluid, and a second valve to control flow of working fluid through the second fluid circulation line so as to selectively remove working fluid from the closed circuit, the first and second valves being configured to be operable to obtain a desired flow rate of working fluid in the closed circuit and desired pressures at the inlet and at the outlet of the pressure regulator, and characterized in that the working fluid in the pressurized working fluid storage tank is water in liquid form.

12. A control device as claimed in claim 11 , characterized in that the hot source comes from the exhaust gas of an internal-combu

Assignees

• Duparchy Alexandre
• Ifp Energies Now

Inventors

• Duparchy Alexandre

Classifications

• F01K23/065 Primary

  the combustion taking place in an internal combustion piston engine, e.g. a diesel engine · CPC title

• F02G5/02

  Profiting from waste heat of exhaust gases · CPC title

• F01K13/02

  Controlling, e.g. stopping or starting · CPC title

• Y02T10/166

  Cross-Sectional Technologies · mapped topic

• Y02T10/12

  Improving ICE efficiencies · CPC title