External combustion engine

Abstract

An external combustion engine comprises a container (11) with a working liquid (12) sealed therein in a state adapted to flow, a heater (13) for heating and vaporizing the working liquid (12) in the container (11), and a cooler (14) for cooling and liquefying the vapor of the working liquid (12) heated and vaporized by the heater (13). The displacement of the working liquid (12) caused by the vapor volume change is output as mechanical energy by being converted into the mechanical energy. A pressure regulating liquid (18) is sealed in a pressure regulating container (16) communicating with the container (11). A pressure regulating unit (19) regulates the internal pressure (Pt) of the pressure regulating container (16). A control unit (21) controls the pressure regulating unit (19) in such a manner that the internal pressure (Pt) is decreased in the case where it is higher than the saturation vapor pressure (Ps1) of the working liquid (12) at the temperature (T1) of a heated portion (11a) of the container for vaporizing the working liquid (12), while the internal pressure (Pt) is increased in the case where it is lower than the saturation vapor pressure (Ps1).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram schematically showing a configuration of a power generating system according to a first embodiment of the invention.

FIG. 2 is a diagram for explaining the operation characteristics of an external combustion engine according to the first embodiment.

FIG. 3A is a PV diagram showing the ideal state of the external combustion engine according to the first embodiment.

FIG. 3B is a PV diagram showing the external combustion engine according to the first embodiment, in which the peak value of the internal pressure of the container is lower than the saturation vapor pressure.

FIG. 3C is a PV diagram showing the external combustion engine according to the first embodiment, in which the peak value of the internal pressure of the container is higher than the saturation vapor pressure.

FIG. 4A is a diagram for explaining the problem posed by the conventional steam engine in which the volume of the working liquid 12 is decreased.

FIG. 4B is a diagram for explaining the problem posed by the conventional steam engine in which the volume of the working liquid 12 is increased.

FIG. 5 is a graph showing the relation between the volume of the working liquid and the efficiency of the external combustion engine.

FIG. 6 is a block diagram schematically showing the control operation according to the first embodiment of the invention.

FIG. 7 is a graph showing the vapor pressure curve of the working liquid.

FIG. 8 is a diagram showing a general configuration of a power generating system according to a second embodiment of the invention.

FIG. 9 is a block diagram schematically showing the control operation according to the second embodiment of the invention.

FIG. 10 is a diagram showing a general configuration of a power generating system according to a third embodiment of the invention.

FIG. 11 is a block diagram schematically showing the control operation according to the third embodiment of the invention.

FIG. 12 is a diagram showing a general configuration of a power generating system according to a fourth embodiment of the invention.

FIG. 13 is a block diagram schematically showing the control operation according to the fourth embodiment of the invention.

FIG. 14 is a diagram showing a general configuration of a power generating system according to a fifth embodiment of the invention.

FIG. 15 is a graph showing the temperature gradient of the pressure regulating container according to the fifth embodiment of the invention.

FIG. 16 is a block diagram schematically showing the control operation according to the fifth embodiment of the invention.

FIG. 17 is a diagram showing a general configuration of a power generating system according to a sixth embodiment of the invention.

FIG. 18 is a block diagram schematically showing the control operation according to the sixth embodiment of the invention.

FIG. 19 is a diagram showing a general configuration of a power-generating system according to a seventh embodiment of the invention.

FIG. 20 is a diagram showing a general configuration of a power generating system according to an eighth embodiment of the invention.

FIG. 21 is a block diagram schematically showing the control operation according to the eighth embodiment of the invention.

FIG. 22 is a diagram showing a general configuration of a power generating system according to a ninth embodiment of the invention.

FIG. 23 is a model diagram showing the thermal resistance of the pressure regulating container according to the ninth embodiment of the invention.

FIG. 24 is a diagram showing a general configuration of a power generating system according to a tenth embodiment of the invention.

FIG. 25 is a diagram showing a general configuration of a power generating system according to an 11th embodiment of the invention.

FIG. 26 is an enlarged sectional view showing the pressure regulating container according to a 12th embodiment of the invention.

FIG. 27 is an enlarged sectional view showing the pressure regulating container according to a 13th embodiment of the invention.

FIG. 28 is an enlarged sectional view showing the pressure regulating container according to a 14th embodiment of the invention.

FIG. 29 is an enlarged sectional view showing the pressure regulating container according to a 15th embodiment of the invention.

FIG. 30 is an enlarged sectional view showing the connecting pipe portion according to a 16th embodiment of the invention.

FIG. 31 is an enlarged sectional view showing the connecting pipe portion according to a 17th embodiment of the invention.

FIG. 32 is a diagram showing a general configuration of a power generating system according to an 18th embodiment of the invention.

FIG. 33 is a block diagram schematically showing the control operation according to the 18th embodiment of the invention.

FIG. 34 is a diagram showing a general configuration of a power generating system according to a 19th embodiment of the invention.

FIG. 35 is a block diagram schematically showing the control operation according to the 19th embodiment of the invention.

FIG. 36 is a diagram showing a general configuration of a power generating system according to a 20th embodiment of the invention.

FIG. 37 is a diagram showing a general configuration of a power generating system according to a 21st embodiment of the invention.

FIG. 38 is a graph showing the relation, as compared with the comparative examples 1 and 2, between the temperature of the cooled portion and the volume of the working liquid according to the 21st embodiment.

Claims

1. An external combustion engine comprising: a container sealed with a working liquid in a way adapted to flow therein; anda heater for heating and vaporizing the working liquid in the container; anda cooler for cooling and liquefying the vapor of the working liquid heated and vaporized by the heater;wherein the displacement of the working liquid caused by the volume change of the vapor is output by being converted into mechanical energy, the external combustion engine further comprising:a pressure regulating container sealed with a pressure regulating liquid and communicating with the container;a pressure regulating means for regulating the internal pressure (Pt) of the pressure regulating container; anda control means for controlling the pressure regulating means in such a manner that the internal pressure (Pt) is reduced in the case where the internal pressure (Pt) is higher than the saturation vapor pressure (Ps1) of the working liquid at the temperature (T1) of a heated portion of the container for vaporizing the working liquid, and the internal pressure (Pt) is increased in the case where the internal pressure (Pt) is lower than the saturation vapor pressure (Ps1).

2. An external combustion engine comprising: a container sealed with a working liquid in a way adapted to flow therein; anda heater for heating and vaporizing the working liquid in the container; anda cooler for cooling and liquefying the vapor of the working liquid heated and vaporized by the heater;wherein the displacement of the working liquid caused by the volume change of the vapor is output by being converted into mechanical energy, the external combustion engine further comprising:a pressure regulating container sealed with a pressure regulating liquid and communicating with the container;a restrictor means disposed in a communicating portion between the pressure regulating container and the container;a pressure regulating means for regulating the internal pressure (Pt) of the pressure regulating container; anda control means for controlling the pressure regulating means in such a manner as to reduce the internal pressure (Pt) of the pressure regulating container if it is higher than a target value (Pc0) and to increase the internal pressure (Pt) if it is lower than the target value (Pc0).

3. The external combustion engine according to claim 2, wherein the control means sets the target value (Pc0) as a value intermediate between the saturation vapor pressure (Ps1) of the working liquid at the temperature (T1) of the heated portion of the container for vaporizing the working liquid and the saturation vapor pressure (Ps2) of the working liquid at the temperature (T2) of the cooled portion of the container for liquefying the vapor of the working liquid.

4. The external combustion engine according to claim 1, wherein the pressure regulating means includes a piston mechanism adapted to reciprocate in the pressure regulating container.

5. The external combustion engine according to claim 4, wherein a gas is sealed, together with the pressure regulating liquid, in the pressure regulating container.

6. The external combustion engine according to claim 1, wherein the pressure regulating means includes a pump mechanism for sucking in the pressure regulating liquid from the pressure regulating container on the one hand and discharging the pressure regulating liquid-to the pressure regulating container on the other hand.

7. The external combustion engine according to claim 2, wherein the pressure regulating means includes a heating means for heating and vaporizing the pressure regulating liquid.

8. The external combustion engine according to claim 7, wherein the pressure regulating container and the heating means are adapted to maintain at least a part of the pressure regulating liquid in a boiling state.

9. The external combustion engine according to claim 7, wherein the heating means includes an electric heater arranged on the outer surface of the pressure regulating container and a temperature controller for controlling the temperature of the electric heater.

10. The external combustion engine according to claim 9, wherein the control means calculates the internal pressure (Pt) based on at least the electric energy (Q3) input to the electric heater, the temperature of the pressure regulating container yet to be heated by the electric heater and the vapor pressure curve of the pressure regulating liquid.

11. The external combustion engine according to claim 7, wherein the heating means includes a pressure regulating heater for heating the pressure regulating liquid with a high-temperature gas as a heat source and a flow rate regulating means for regulating the flow rate (mg) of the high-temperature gas under the control of the control means.

12. The external combustion engine according to claim 11, wherein the control means calculates the internal pressure (Pt) based on at least the temperature (Tgi) of the high-temperature gas before heating the pressure regulating container, the temperature (Tgo) of the high-temperature gas after heating the pressure regulating container, the flow rate (mg), the temperature (T2) of a cooled portion of the container for liquefying the vapor of the working liquid and the vapor pressure curve of the pressure regulating liquid.

13. An external combustion engine comprising: a container sealed with a working liquid in a way adapted to flow therein;a heater for heating and vaporizing the working liquid in the container; anda cooler for cooling and liquefying the vapor of the working liquid heated and vaporized by the heater;wherein the displacement of the working liquid caused by the volume change of the vapor is output by being converted into the mechanical energy, the external combustion engine further comprising:a pressure regulating container sealed with a pressure regulating liquid and communicating with the container;a heating means for heating and vaporizing the pressure regulating liquid; anda restrictor means disposed in the communicating portion between the pressure regulating container and the container;wherein the pressure regulating container and the heating means are adapted to maintain at least a part of the pressure regulating liquid in a boiling state; andwherein the pressure regulating container is adapted to have such a thermal resistance that the temperature (Th) of the high-temperature portion of the pressure regulating container for vaporizing the pressure regulating liquid assumes a value intermediate between the temperature (T1) of the heated portion of the container for vaporizing the working liquid and the temperature (T2) of the cooled portion of the container for liquefying the vapor of the working liquid.

14. The external combustion engine according to claim 13, wherein the heat source of the heating means is a high-temperature gas.

15. The external combustion engine according to claim 14, wherein the high-temperature gas is used also a heat source of the heated portion of the container for vaporizing the working liquid.

16. The external combustion engine according to claim 15, wherein the heating means is located downstream of the heated portion in the high-temperature gas flow.

17. The external combustion engine according to claim 13, further comprising a heat conduction means for conducting the heat of the heated portion to the heating means.

18. The external combustion engine according to claim 7, wherein the pressure regulating container is provided with a volume regulating mechanism for increasing the volume of the pressure regulating container upon vaporization of the pressure regulating liquid.

19. The external combustion engine according to claim 18, wherein the volume regulating mechanism includes a mass-like elastic member disposed in the pressure regulating container and adapted to be compressed and reduced in volume upon vaporization of the pressure regulating liquid.

20. The external combustion engine according to claim 18, wherein a partitioning plate for separating the internal space of the pressure regulating container into a first space sealed with the pressure regulating liquid arid a second space sealed with a gas is slidably disposed in the pressure regulating container;wherein upon vaporization of the pressure regulating liquid, the partitioning plate is pressed against the second space thereby to compress the gas; andwherein the volume regulating mechanism includes the partitioning plate and the gas.

21. The external combustion engine according to claim 18, wherein a partitioning plate for separating the internal space of the pressure regulating container into a first space sealed with the pressure regulating liquid and a second space provided with an elastic member is slidably disposed in the pressure regulating container;wherein upon vaporization of the pressure regulating liquid, the partitioning plate is pressed against the second space thereby to compress the elastic member; andwherein the volume regulating mechanism includes the partitioning plate and the elastic member.

22. The external combustion engine according to claim 7, wherein the pressure regulating container is provided with a temperature regulating mechanism for reducing the temperature of the pressure regulating liquid upon vaporization of the pressure regulating liquid.

23. An external combustion engine comprising: a container sealed with a working liquid in a state adapted to flow therein;a heater for heating and vaporizing the working liquid in the container; anda cooler for cooling and liquefying the vapor of the working liquid heated and vaporized by the heater;wherein the displacement of the working liquid caused by the volume change of the vapor is output by being converted into the mechanical energy; the external combustion engine further comprising:a plurality of pressure regulating containers sealed with a pressure regulating liquid and communicating with the container;pressure means for applying different pressures to the interior of the plurality of the pressure regulating containers, respectively;a plurality of on/off valves for opening/closing communicating portions between the plurality of the pressure regulating containers and the container, respectively; anda control means for controlling the plurality of the on/off valves in such a manner that, in the case where the average value (Pca) of the internal pressure (Pc) of the container is lower than a target value (Pc0), only the communicating portion of that one of the plurality of the pressure regulating containers which has the internal pressure (Pt) higher than and nearest to the target value (Pc0) is opened, while in the case where the average value (Pca) is higher than the target value (Pc0), on the other hand, only the communicating portion of that one of the plurality of the pressure regulating containers which has the internal pressure (Pt) lower than and nearest to the target value (Pc0) is opened.

24. The external combustion engine according to claim 1, wherein the pressure regulating liquid is the same liquid as the working liquid.

25. An external combustion engine comprising: a container sealed with a working liquid in a way adapted to flow therein;a heater for heating and vaporizing the working liquid in the container; anda cooler for cooling and liquefying the vapor of the working liquid heated and vaporized by the heater;wherein the displacement of the working liquid caused by the vapor volume change is output by being converted into the mechanical energy; the external combustion engine further comprising:an expansion and contraction portion formed on the container and capable of increasing and decreasing the volume by extension and contraction;an extension and contraction drive mechanism for expanding and contracting the expansion and contraction portion; anda control means for controlling the extension and contraction mechanism in such a manner as to extend the expansion and contraction portion in the case where the average value (Pca) of the internal pressure (Pc) of the container is larger than a target value (Pc0) while the expansion and contraction portion is contracted in the case where the average value (Pca) is smaller than the target value (Pc0).

26. An external combustion engine comprising: a container sealed with a working liquid in a way adapted to flow therein;a heater for heating and vaporizing the working liquid in the container; anda cooler for cooling and liquefying the vapor of the working liquid heated and vaporized by the heater;wherein the displacement of the working liquid caused by the vapor volume change is output by being converted into the mechanical energy; the external combustion engine further comprising:a temperature control means for controlling the temperature of the working liquid; anda control means for controlling the temperature control means in such a manner that in the case where the internal pressure (Pc) of the container is higher than the saturation vapor pressure (Ps1) of the working liquid at the temperature (T1) of the heated portion of the container for vaporizing the working liquid, the temperature of the working liquid is decreased, while in the case where the internal pressure (Pc) is lower than the saturation vapor pressure (Ps1), the temperature of the working liquid is increased.

27. An external combustion engine comprising: a container sealed with a working liquid in a state adapted to flow therein;a heater for heating and vaporizing the working liquid in the container; anda cooler for cooling and liquefying the vapor of the working liquid heated and vaporized by the heater;wherein the displacement of the working liquid caused by the vapor volume change is output by being converted into the mechanical energy; the external combustion engine further comprising:a volume regulating mechanism for increasing the volume of the container with the increase in the temperature (T2) of the cooled portion of the container for liquefying the vapor of the working liquid and decreasing the volume thereof with the decrease in the temperature (T2) of the cooled portion.

28. The external combustion engine according to claim 27, comprising: a first partitioning plate, adapted to slide in the container, for separating the internal space of the container into a first space sealed with a working liquid and a second space sealed with a first gas;a second partitioning plate, disposed in opposed relation to the first partitioning plate and adapted to slide in the container, for separating the internal space of the container into the first space and a third space sealed with a second gas;a connecting portion for connecting the first and second partitioning plates; anda heat conduction member for thermally connecting the first gas and the cooled portion;wherein the volume of the first space is increased by the slide of the first and second partitioning plates toward the third space, and the volume of the first space is decreased by the slide of the first and second partitioning plates toward the second space; andwherein the volume regulating mechanism includes the first partitioning plate, the second partitioning plate, the connecting portion, the first gas, the second gas and the heat conduction member.

29. The external combustion engine according to claim 28, wherein the volume regulating mechanism is adapted so that the force (F3) exerted on the second partitioning plate by the second gas is larger than the maximum value (Fmax) of the force exerted on the second partitioning plate by the working liquid.

30. An external combustion engine comprising: a container sealed with, and in a state adapted to flow therein, a first working liquid and a second working liquid smaller in the coefficient of linear expansion than and insoluble in the first working liquid;a heater for heating and vaporizing the second working liquid in the container; anda cooler for cooling and liquefying the vapor of the second working liquid heated and vaporized by the heater;wherein the displacement of the first working liquid caused by the vapor volume change is output by being converted into the mechanical energy.