External combustion engine

Abstract

An external combustion engine comprising a container (11) sealed with a working liquid (12) in a way adapted to allow the liquid to flow therein, a heating unit (13, 30) for heating and vaporizing the working liquid (12) in the container (11), and a cooling unit (14) for cooling and liquefying the vapor of the working liquid (12) heated and vaporized by the heating unit (13, 30) is disclosed, wherein the displacement of the working liquid (12) caused by the volume change of the vapor is output by being converted into mechanical energy. A pressure regulating unit (16, 60, 63) regulates the internal pressure (Pc) of the container (11). A control unit (21) controls the pressure regulating unit (16, 60, 63) based on at least the temperature (T1) of the heated portion (11a) of the container (11) for vaporizing the working liquid (12). The control unit (21) calculates the temperature (T1) based on at least the heat quantity (Q) applied from the heating unit (13 30) to the working liquid (12).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a general configuration of a power generating device 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 of the invention.

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

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

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

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

FIG. 4B is a diagram for explaining the problem posed by the conventional steam engine, showing a state 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 showing a general control operation according to the first embodiment.

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

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

FIG. 9 is a diagram showing a general configuration of the power generating device according to a third embodiment of the invention.

FIG. 10 is a block diagram showing a general control operation according to the third embodiment.

FIG. 11 is a diagram showing a general configuration of the power generating device according to a fourth embodiment of the invention.

FIG. 12 is a block diagram showing a general control operation according to the fourth embodiment.

FIG. 13 is a diagram showing a general configuration of the power generating device according to a fifth embodiment of the invention.

FIG. 14 is a block diagram showing a general control operation according to the fifth embodiment.

FIG. 15 is a diagram showing a general configuration of the power generating device according to a sixth embodiment of the invention.

FIG. 16 is a graph showing the temperature gradient of a regulating container according to the sixth embodiment of the invention.

FIG. 17 is a block diagram showing a general control operation according to the sixth embodiment.

FIG. 18 is a diagram showing a general configuration of the power generating device according to a seventh embodiment of the invention.

FIG. 19 is a block diagram showing a general control operation according to the seventh embodiment.

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

FIG. 21 is a block diagram showing a general control operation according to the eighth embodiment.

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

FIG. 23 is a time chart for explaining the operation of a control unit according to the ninth embodiment of the invention.

Claims

1. An external combustion engine for outputting mechanical energy by converting the displacement of a working liquid caused by the volume change of the vapor of the working liquid into mechanical energy, comprising: a container sealed with a working liquid in a way adapted to allow the liquid to flow therein;a heating means for heating and vaporizing the working liquid in the container;a cooling means for cooling and liquefying the vapor of the working liquid heated and vaporized by the heating means;a pressure regulating means for regulating the internal pressure (Pc) of the container; anda control means for controlling the pressure regulating means based on at least the temperature (T1) of the heated portion of the container for vaporizing the working liquid;wherein the control means calculates the temperature (T1) based on at least the heat quantity (Q) applied to the working liquid from the heating means.

2. The external combustion engine according to claim 1, wherein the control means calculates the saturated vapor pressure (Ps1) of the working liquid at the temperature (T1) based on the temperature (T1) and the vapor pressure curve of the working liquid.

3. The external combustion engine according to claim 2, wherein the control means controls the pressure regulating means in such a manner that the internal pressure (Pc), if not lower than the saturated vapor pressure (Ps1), is decreased.

4. The external combustion engine according to claim 2, wherein the control means controls the pressure regulating means in such a manner that the internal pressure (Pc), if not lower than the saturated vapor pressure (Ps1), is decreased and, if not higher than the saturated vapor pressure (Ps1), is increased.

5. The external combustion engine according to claim 2, wherein the control means controls the pressure regulating means in such a manner that the internal pressure (Pc) is decreased in the case where the average value (Pca) of the internal pressure (Pc) is not lower than the target value (Pc0) calculated based on at least the saturated vapor pressure (Ps1) and the internal pressure (Pc) is increased in the case where the average value (Pca) is not higher than the target value (Pc0).

6. A temperature calculating device used with an external combustion engine for outputting mechanical energy by converting the displacement of a working liquid caused by the vapor volume change of the working liquid into mechanical energy, comprising a container sealed with the working liquid adapted to allow the liquid to flow therein, a heating means for heating and vaporizing the working liquid in the container and a cooling means for cooling and liquefying the vapor of the working liquid heated and vaporized by the heating means, wherein the temperature (T1) of the heated portion of the container for vaporizing the working liquid is calculated based on at least the heat quantity (Q) applied to the working liquid from the heating means.

7. The temperature calculating device for the external combustion engine according to claim 6, wherein the control means calculates the temperature (T1) using Equation (1) below: T1=Q/(m·Cp)−T0   (1)where m is the mass of the heated portion, Cp the specific heat of the heated portion, and T0 the temperature of the heated portion before being heated by the heating means.

8. The temperature calculating device for the external combustion engine according to claim 6, wherein the heating means is an electric heater, the temperature calculating device further comprising a wattage detecting means for detecting the wattage (Q1) input to the electric heater, andwherein the control means calculates the temperature (T1) using the wattage (Q1) in place of the heat quantity (Q).

9. The temperature calculating device for the external combustion engine according to claim 6; wherein the heating means is a heater for exchanging heat with a high-temperature gas, the temperature calculating device comprising,a first temperature detecting means for detecting the temperature (Tgi) of the high-temperature gas before exchanging heat with the heated portion,a second temperature detecting means for detecting the temperature (Tgo) of the high-temperature gas after exchanging heat with the heated portion, anda flow rate detecting means for detecting the flow rate (mg) of the high-temperature gas;wherein the control means calculates the heat quantity (Q) based on at least the temperature (Tgi) of the high-temperature gas before exchanging heat with the heated portion, the temperature (Tgo) of the high-temperature gas after exchanging heat with the heated portion and the flow rate (mg).

10. The temperature calculating device for the external combustion engine according to claim 9, wherein the control means calculates the heat quantity (Q) using Equation (2) below: Q=mg·Cgp·(Tgi−Tgo)   (2)