Heat engine

Abstract

The present invention relates to a heat engine comprising: a first heat source; a second heat source; a module (3') for alternately displacing the thermodynamic fluid between a cold portion (4) connected to the first heat source (1) and a hot portion (5) connected to the second heat source (2), said module (3') comprising a chamber able and intended to contain a thermodynamic fluid, the chamber being connected to a supply outlet of thermodynamic fluid (G), said module (3') further comprising a displacer capable of moving in said chamber alternately between the cold portion (4) and the hot portion (5); a first conversion unit (6) for converting a pressure difference of the thermodynamic fluid into mechanical energy, the conversion unit (6) comprising at least one circuit (7) that includes at least one motor (8) and is connected to the supply outlet of thermodynamic fluid (G); a first control unit placed in the first conversion unit (6) for controlling the phase of the thermodynamic cycle in said module (3'); a second control unit of said module (3') for controlling the displacement of said displacer alternately between the hot portion (5) and the cold portion (4).

Description

[0001] [The present invention relates to the field of thermal machines. Document US2006 / 059912 A1 describes an example of such a thermal machine.

[0002] The control of thermal machines such as classic Stirling engines, for which there is a mechanical coupling of the moving parts, is complex because the rotation speed depends mainly on the temperature difference between the hot and cold source. As a result, the actual thermodynamic cycle of this type of thermal machine is very far from the ideal Stirling cycle, composed of two isochoric transformations and two isotherms. The efficiency is thus much lower than the theoretical efficiency.

[0003] Improvements have been made to improve the cycle and get as close as possible to the theoretical cycle. For example, publication WO2010 / 043469A1 proposes a method for controlling a Stirling cycle thermal engine with fluidic pistons. The method is based on the Stirling cycle in which the movement of the thermodynamic fluid is done with management of the working fluid. This logic has the major drawback that the working fluid transits between the hot and cold parts, causing significant heat losses. In addition, isothermal compression requires regulation by means of a hydraulic compressor.

[0004] Publication WO84 / 00399A1 discloses an example of mechanical decoupling between the displacer positions and the working piston positions for a Stirling engine powered by external combustion. However, the system works with an additional hydraulic piston to the working piston, which complicates the engine and the control of the assembly, especially since a pump is integrated between the pistons to compress the air before mixing it with the fuel.

[0005] Another area of ​​low-temperature heat-to-electricity conversion processes is ORC (Organic Rankine Cycle) systems, which take advantage of the phase change of an organic fluid. These systems can theoretically recover energy from very low-temperature sources but are not currently economically viable for temperatures below 100 degrees Celsius. They also require continuous cycle management based on the temperatures of the cold and hot sources to ensure that the fluid is single-phase, i.e., either gaseous or liquid, when passing through the expansion and compression components. Furthermore, a compressor is essential to achieve compression between the low-pressure and high-pressure parts.

[0006] The present invention aims to overcome at least one of these drawbacks and aims to propose an alternative thermal machine solution.

[0007] For this purpose, the invention relates to a thermal machine according to claim 1.

[0008] The invention will be better understood from the following description, which relates to several preferred embodiments, given as non-limiting examples, and explained with reference to the appended schematic drawings, in which: [ Fig. 1 ] there figure 1 represents a global diagram representative of the thermal machine according to the type of module, [ Fig. 2 ] there figure 2 represents the Temperature T- Entropy S diagram of a thermodynamic cycle of the heat engine for carbon dioxide, [ Fig. 3 ] there figure 3 represents a schematic view of a thermal machine according to a first variant of the invention illustrating the first control unit, [ Fig. 4 ] there figure 4 represents a schematic view of a thermal machine according to a second variant of the invention illustrating the first control unit, [ Fig. 5 ] there figure 5 represents a schematic view of a module for a thermal machine illustrating a second control unit according to a first possibility, [ Fig. 6 ] there figure 6 represents a schematic view of a module for a thermal machine illustrating the second control unit according to a second possibility, [ Fig. 7 ] there figure 7 represents a schematic view of a module for a thermal machine illustrating the second control unit, [ Fig. 8 ] there figure 8 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to a first example, [ Fig. 9 ] there figure 9 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to a second example, [ Fig. 10 ] there figure 10 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to a third example, [ Fig. 11 ] there figure 11 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to a fourth example, [ Fig. 12 ] there figure 12 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to the third example and illustrates its operation, [ Fig. 13 ] there figure 13 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to the third example and illustrates its operation, [ Fig. 14 ] there figure 14 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to the third example and illustrates its operation, [ Fig. 15 ] there figure 15 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to the third example and illustrates its operation, [ Fig. 16 ] there figure 16 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to the third example and illustrates its operation, [ Fig. 17 ] there figure 17 represents a schematic view of a thermal machine with a so-called phase opposition architecture according to the third example and illustrates its operation, [ Fig. 18 ] there figure 18 represents a schematic view of a thermal machine according to the first variant of the invention in which the pressure limiter is replaced by an additional pressure accumulator, [ Fig. 19 ] there figure 19 represents a sectional view of a module comprising a cartridge.

[0009] A thermal machine is capable and intended to carry out at least one conversion of thermal energy into mechanical energy comprising at least one thermodynamic fluid and capable and intended to implement a thermodynamic cycle comprising at least one isochoric heating phase 1-2, optionally one isobaric heating phase 2-3, one expansion phase 3-4 and one isobaric cooling phase 4-1 ( figure 2 ).

[0010] The thermal machine includes at least: a first heat source 1 at a first temperature T1 configured to contain and transmit thermal energy to at least one heat transfer fluid ( figure 1 ), a second heat source 2 at a second temperature T2 configured to contain and transmit thermal energy to at least one heat transfer fluid, the first and second temperatures T1 and T2 being different ( figure 1 ), at least one module 3, 3' for moving the thermodynamic fluid alternately between a cold part 4 connected to the first heat source 1 and a hot part 5 connected to the second heat source 2 ( figures 3 à 16 ), said at least one module 3, 3' comprising at least the cold part 4, said at least one module 3, 3' comprising a first heat transfer fluid supply circuit A, B connected to the first heat source 1 and to the cold part 4, said at least one module 3, 3' comprising at least the hot part 5, said at least one module 3, 3' comprising a second heat transfer fluid supply circuit C, D connected to the second heat source 2 and to the hot part 5, said at least one module 3, 3' comprising at least one chamber suitable and intended to contain said at least one thermodynamic fluid and which is connected to at least one thermodynamic fluid supply outlet G at a first pressure P1 or to a hydraulic fluid supply outlet E at a second pressure P2,at least one first unit 6 for converting a pressure difference of the thermodynamic fluid into mechanical energy comprising at least one circuit 7 which comprises at least mechanical conversion means, preferably a motor 8, said first conversion unit 6 being connected to the thermodynamic fluid supply outlet G (, figures 4 And 11 ) or at the hydraulic fluid supply outlet E ( figures 3 , 8 has 10 ).

[0011] According to the invention, the thermal machine is characterized in that said at least one module 3, 3' further comprises at least one movable displacer in said chamber alternately between the cold part 4 and the hot part 5, said chamber being suitable and intended to contain said at least one high-pressure thermodynamic fluid having pressures between 50 bars and 300 bars and in the supercritical state, in that it comprises at least a first control unit at least partly arranged in the first conversion unit 6 arranged at least to control the phase in which the thermodynamic cycle is located in said at least one module 3, 3', and in that it comprises a second control unit of said at least one module 3, 3' arranged to control the movement of said at least one displacer alternately between the hot part 5 and the cold part 4.

[0012] Advantageously, the heat engine according to the invention allows the conversion of heat, preferably at low temperature, that is to say for first and second heat sources 1, 2 whose temperature T1, T2 does not exceed 150 degrees Celsius, into mechanical energy. This conversion is carried out according to a closed thermodynamic cycle using a thermodynamic fluid preferably in supercritical phase alternately heated and cooled via the first heat source 1 and the second heat source 2. As illustrated in figure 2 the thermodynamic cycle comprises at least one 1-2 isochoric heating phase, optionally one 2-3 isobaric heating phase, one preferably polytropic 3-4 expansion phase and one 4-1 isobaric cooling phase. The supercritical thermodynamic cycle contains one 1-2 isochoric heating which is supplemented by one 2-3 isobaric heating if the pressure during heating exceeds a determined limit value between 100 bar and 200 bar. When the thermodynamic fluid is carbon dioxide, the pressure ranges of the thermodynamic fluid are typically between 74 bar and 350 bar, preferably 74 bar and 250 bar and the temperature ranges are between 0 degrees Celsius and 150 degrees Celsius, preferably between 10 degrees Celsius and 100 degrees Celsius. These different phases of the thermodynamic cycle can be controlled in order to modulate the actual thermodynamic cycle followed by the thermodynamic fluid.This allows the efficiency and the average power to be continuously influenced. The first conversion unit 6 advantageously allows the conversion of the pressure of the thermodynamic fluid at the thermodynamic fluid supply outlet G or of the hydraulic fluid at the hydraulic fluid supply outlet E into mechanical movement. The energy recovery by the first conversion unit 6 can thus be carried out using a hydraulic fluid different from the thermodynamic fluid (. figures 3 , 8 has 10 ) or directly with the thermodynamic fluid ( figures 4 And 11). The first control unit allows the control of the completion state of each thermodynamic transformation phase and therefore of the thermodynamic cycle, in particular by detecting the points of the thermodynamic cycle, for example by detecting pressure and / or flow rate as described below. The second control unit allows the thermodynamic fluid to be moved alternately in the chamber from the cold part 4 to the hot part 5 and to modulate the heat supply of the module 3, 3'. For example, the second control unit allows the management of the pressure and / or flow rate from the first and second heat sources 1, 2 as described below. As a result, the efficiency of the heat engine and its average power density can consequently be modulated at will, offering the possibility of optimizing one or the other depending on the availability of the first and second heat sources 1, 2.

[0013] The mover is one or more mechanical parts.

[0014] Preferably, the expansion 3, 4 is polytropic, that is to say it is neither isothermal nor adiabatic. Thus, the expansion is variable and can approach either an isothermal expansion 3, 4' or an adiabatic expansion 3, 4" ( figure 2 ).

[0015] Preferably, the isochoric heating phase 1-2 does not correspond to an ideal / theoretical isochoric heating, but the heating phase approaches this ideal or theoretical isochore with a deviation value which is preferably between 0 and 20 percent.

[0016] Preferably, the heating phase isobars 2-3 and / or the cooling phase 4-1 do not correspond to ideal / theoretical isobars, but approach them with a deviation value which is preferably between 0 and 20 percent.

[0017] Module 3 comprises at least one chamber suitable and intended to contain a high-pressure thermodynamic fluid, i.e. for pressures between 50 bars and 300 bars, preferably between 80 bars and 250 bars, and in the supercritical state, and which is connected to the thermodynamic fluid supply outlet G. Module 3 is said to be basic. This is the case in particular for modules 3 described in the figures 4 And 11 .

[0018] In the case where the module 3' further comprises a hydraulic piston 36 connected to the hydraulic fluid supply outlet E, this module 3' is said to be hybrid. This is the case in particular for the modules 3' described in the figures 3 , 8 has 10 .

[0019] Alternatively, the so-called basic module 3 can be connected to a hydraulic piston 36 which is outside the module 3. Each basic module 3 or association of modules 3 can be coupled to one or more high-pressure hydraulic piston(s) 36 outside the module(s) 3 and maintained at temperature by one of the first / second heat sources 1, 2. The hydraulic piston 36 thus makes it possible to transmit the pressure of the supercritical fluid to a hydraulic fluid. A hydraulic reduction ratio, not shown, can also be produced within the hydraulic piston 36 so as to modify the characteristics of the pressure and the volume of oil displaced. This can have a certain advantage in certain cases to facilitate the sizing of the charging system, in particular to adapt to the pressure / flow characteristics of the hydraulic motor 12.If no reduction ratio is required, then the hydraulic piston 36 can be in the form of a so-called "liquid" piston, i.e. without a solid interface between the two fluids provided that they are immiscible and insoluble with each other. This makes it possible to avoid losses due to friction of seals.

[0020] As illustrated by the figure 3 , according to a first variant embodiment of the invention, said first conversion unit 6 comprises at least one hydraulic pressure accumulator 11 connected downstream of the mechanical conversion means, preferably of the motor 8, which is a hydraulic motor 12, said pressure accumulator 11 being capable and intended to maintain the pressure of the circuit 7 greater than or equal to the critical pressure of the thermodynamic fluid.

[0021] Advantageously, the pressure accumulator 11 ensures that the pressure of the hydraulic fluid in the circuit 7 is maintained above or equal to the critical pressure of the thermodynamic fluid for the entire thermodynamic cycle and in particular during the isobaric cooling phase. For carbon dioxide, this critical pressure is substantially equal to 73.77 bars. Consequently, the precharged pressure of the pressure accumulator 11 is preferably between 73 and 85 bars, preferably equal to 80 bars. In this configuration, the thermodynamic fluid contained in one or more so-called hybrid module(s) 3' is alternately heated, then cooled and works against a quasi-constant assimilated pressure of the pressure accumulator 11. The pressure differences of the thermodynamic fluid, then of the hydraulic fluid are converted into mechanical energy by the hydraulic motor 12.

[0022] As illustrated by the figure 4 , according to a second variant embodiment of the invention, said first conversion unit 6 comprises at least one pressure accumulator 11 connected downstream of the mechanical conversion means, preferably of the engine 8 which is a thermodynamic fluid turbine 14 preferably in the supercritical state, said pressure accumulator 11 being capable and intended to maintain the pressure of the circuit 7 greater than or equal to the critical pressure of the thermodynamic fluid.

[0023] Advantageously, the pressure accumulator 11 ensures that the pressure of the thermodynamic fluid in the circuit 7 is maintained above or equal to the critical pressure of the thermodynamic fluid for the entire thermodynamic cycle and in particular during the isobaric cooling phase. For carbon dioxide, this critical pressure is substantially equal to 73.77 bars. Consequently, the precharged pressure of the pressure accumulator 11 is preferably between 73 and 85 bars, preferably equal to 80 bars. In this configuration, the thermodynamic fluid contained in one or more so-called basic module(s) 3 is alternately heated then cooled and works against a quasi-constant assimilated pressure of the pressure accumulator 11. The only differences in pressure of the thermodynamic fluid are converted into mechanical energy by the thermodynamic fluid turbine 14.

[0024] Preferably, said first control unit comprises at least one pressure and / or flow rate measuring member 9 arranged to control the phase in which the thermodynamic cycle is located and in particular to determine the completion of each phase of the cycle. Said pressure and / or flow rate measuring member 9 is preferably arranged between the chamber and said pressure accumulator 11.

[0025] Advantageously, said first control unit makes it possible, thanks to at least one pressure and / or flow rate measuring member 9 arranged in the circuit 7 or in the chamber, to monitor the evolution of the different phases of the thermodynamic cycle by measuring the pressure of the thermodynamic or hydraulic fluid in the chamber or in the circuit 7 and / or by measuring the flow rate of the hydraulic fluid in the circuit 7. This pressure and / or flow rate measuring member 9 is arranged upstream of the motor 8 or at the motor 8. This configuration makes it possible to monitor the state of completion of each thermodynamic transformation and therefore of the thermodynamic cycle, in particular by detecting11 the points of the cycle by detecting and monitoring the pressure and / or flow rate of the thermodynamic fluid or the hydraulic fluid.

[0026] Preferably as illustrated by the figures 3 And 4, according to the first embodiment of the invention and the second embodiment, said first control unit comprises two pressure and / or flow rate measuring members 9 of the circuit 7 in the form of a pressure sensor 90 and a rotation speed sensor 10.

[0027] The rotation speed sensor 10 is arranged at the motor 8 and allows indirect measurement of the flow rate in the circuit 7. For example, the rotation speed sensor 10 can allow, via the measurement of the flow rate of the hydraulic fluid in the circuit 7, to conclude that at the end of the isobaric heating phase, the system is at equilibrium.

[0028] The pressure sensor 90 allows direct measurement of the pressure of the hydraulic fluid in the circuit 7 ( figure 3 ) or a direct measurement of the pressure of the thermodynamic fluid in circuit 7 ( figure 4 ).

[0029] According to the first embodiment variant illustrated in the figure 3 , said pressure and / or flow rate measuring member 9 is arranged between the hydraulic fluid supply outlet E and said pressure accumulator 11. Said pressure and / or flow rate measuring member 9 is arranged in the circuit 7.

[0030] According to the second embodiment illustrated in the figure 4 , said pressure and / or flow rate measuring member 9 is arranged between the thermodynamic fluid supply outlet G and said pressure accumulator 11. Said pressure and / or flow rate measuring member 9 is arranged in the circuit 7.

[0031] Preferably and as illustrated by the figures 3 And 4, said first control unit comprises at least one pressure and / or flow rate regulating element 13 of the circuit 7 arranged at least to control / pilot the isobaric heating phase and / or the expansion phase of the thermodynamic cycle, said at least one pressure and / or flow rate regulating element 13 being arranged between the thermodynamic fluid supply outlet G or the hydraulic fluid supply outlet E and said pressure accumulator 11.

[0032] Advantageously, said first control unit makes it possible in particular, thanks to at least one pressure and / or flow regulation element 13, to supply or not supply the motor 8. Said first control unit also makes it possible, thanks to at least one pressure and / or flow regulation element 13, to control the movement of the thermodynamic fluid ( figure 4 ) or hydraulic fluid ( figure 3 ) in circuit 7 to control / pilot the isobaric heating phase and / or the expansion phase of the thermodynamic cycle

[0033] Preferably, said at least one pressure and / or flow regulating element 13 is chosen from a pressure limiter 16 ( figure 3 ) and / or a flow regulator, and / or a hydraulic valve 15 ( figure 3 ) and / or an adjustable flow limiter and / or a variable throttle orifice 17 ( figure 4 ) or an additional pressure accumulator 30 ( figure 18 ).

[0034] According to the first embodiment variant illustrated in the figure 3 , said at least one pressure and / or flow regulating element 13 is arranged between the hydraulic fluid supply outlet E and said pressure accumulator 11.

[0035] According to the first embodiment variant illustrated in the figure 3 , said first control unit comprises two pressure and / or flow regulating elements 13 in the form of an adjustable pressure limiter 16 and a hydraulic valve 15.

[0036] Advantageously, the adjustable pressure limiter 16 makes it possible to ensure the transition from the isochoric heating phase to the isobaric heating phase at a determined pressure. At the end of the isobaric heating, when the system is at equilibrium, the hydraulic valve 15 is opened to carry out the polytropic expansion then the cooling of the fluid after inversion of the displacers in the module(s) 3'.

[0037] As illustrated by the figure 18 , the adjustable pressure limiter 16 can be replaced by an additional pressure accumulator 30 preferably precharged to the isobaric heating pressure.

[0038] This configuration allows the storage of energy in the additional pressure accumulator 30 during the isochoric heating phase.

[0039] According to the second embodiment illustrated in the figure 4 , said at least one pressure and / or flow regulating element 13 is arranged between the thermodynamic fluid supply outlet G and said pressure accumulator 11.

[0040] According to the second embodiment illustrated in the figure 4 , said first control unit comprises a pressure and / or flow regulating element 13 in the form of a variable throttle orifice 17.

[0041] Advantageously, in this second variant the adjustable pressure limiter 16 and the hydraulic valve 15 of the first variant can be replaced by a single variable throttle orifice 17 so as to be able to actively control the isobaric heating phase and the preferably polytropic expansion phase.

[0042] In the first conversion unit, the circuit 7 may comprise one or more pipes, preferably insulated, which in particular make it possible to connect the thermodynamic fluid supply outlet G or the hydraulic fluid supply outlet E to the pressure accumulator 11 and / or to the pressure and / or flow rate measuring member 9 and / or to the pressure and / or flow rate regulating element 13 and / or to the motor 8.

[0043] Preferably and as illustrated by the figures 3 And 4 , the machine further comprises a second unit 18 for converting mechanical energy into electrical energy connected to said first conversion unit 6 downstream of said motor 8.

[0044] Advantageously, the second conversion unit 18 makes it possible to convert the mechanical energy coming from the motor 8 into electrical energy.

[0045] Preferably and as illustrated by the figures 3 And 4, the second conversion unit 18 comprises at least one inertia 19 connected on the one hand to a coupling 20 and on the other hand to a generator 21.

[0046] Preferably, the module 3, 3' comprises at least one piston (not shown) contained in a cylinder (not shown) connected to a working fluid supply circuit J, H by a first end and a second end of the cylinder to control the movement of the movable piston in the cylinder and the displacer and the piston are coupled to each other.

[0047] Advantageously, the movement of the piston causes the movement of the displacer in the chamber between the hot part 5 and the cold part 4. The coupling between the displacer and the piston is preferably a magnetic coupling to limit friction losses in particular.

[0048] Preferably and as illustrated by the figure 5 , according to a first possibility the second control unit comprises at least one first pressure and / or flow rate regulating member at the first end of the cylinder and at least one second pressure and / or flow rate regulating member at the second end of the cylinder to maintain or vary a pressure difference between the first end and the second end so as to alternately move said at least one displacer between the hot part 5 and the cold part 4.

[0049] Advantageously, the second control unit allows the management of the position of the thermodynamic fluid between the hot part 5 and the cold part 4 in at least one module 3, 3'. Each module 3, 3' contains a certain mass of thermodynamic fluid preferably in supercritical phase which is alternately brought into contact with the first heat source 1 then with the second heat source 2 by means of one or more displacer(s). This or these displacer(s) function as free pistons whose stop-type position is determined solely by the pressure difference between the first end of the cylinder and the second end of the cylinder. In this case, the working fluid supply circuit J, H is independent of the regulation of the pressure of said first heat transfer fluid supply circuit A, B and of said second heat transfer fluid supply circuit C, D.

[0050] Preferably and as illustrated by the figures 6 And 7 , the working fluid supply circuit J, H is formed of said first heat transfer fluid supply circuit A, B and said second heat transfer fluid supply circuit C, D.

[0051] Preferably and according to a possibility not shown, the second control unit comprises at least a first member for regulating the pressure and / or the flow rate of the first heat source 1 and a second member for regulating the pressure and / or the flow rate of the second heat source 2, the first member for regulating the pressure and / or the flow rate and the second member for regulating the pressure and / or the flow rate being configured to maintain or vary a pressure difference between the first heat source 1 and the second heat source 2 so as to alternately move said at least one displacer between the cold part 4 and the hot part 5.

[0052] Preferably, the first heat source 1 comprises at least one pump, preferably hydraulic, which forms the first pressure and / or flow rate regulating member and the second heat source 2 comprises a second pump, preferably hydraulic, which forms the second pressure and / or flow rate regulating member.

[0053] The control of the movement of the preferably supercritical hydraulic fluid in the module 3, 3' is therefore carried out as simply as possible by adequate regulation of the preferably hydraulic pumps (not shown) of the first and second heat sources 1, 2 in order to create / maintain the differential pressure between the first and second heat transfer fluid supply circuits A, B and C, D required for the movement of the displacer(s).

[0054] If regulation of the preferably hydraulic pumps is not possible, regulation of the first / second heat transfer fluid supply circuits A, B and C, D with added elements described below in the second possibility (pressure limiter 26, 27 and / or a flow regulator 28, 29) then makes it possible to precisely control the flow rate and pressure in each part of the module(s) 3, 3'.

[0055] Preferably and as illustrated by the figure 6 , according to a second possibility the second control unit comprises at least a third pressure and / or flow rate regulating member of the first supply circuit A, B and a fourth pressure and / or flow rate regulating member of the second supply circuit C, D, the third pressure and / or flow rate regulating member and the fourth pressure and / or flow rate regulating member being configured to maintain or vary a pressure difference between the first supply circuit A, B and the second supply circuit C, D so as to alternately move said at least one displacer between the cold part 4 and the hot part 5.

[0056] Advantageously, the second control unit allows the management of the position of the thermodynamic fluid between the hot part 5 and the cold part 4 in at least one module 3, 3'. Each module 3, 3' contains a certain mass of thermodynamic fluid preferably in supercritical phase which is alternately brought into contact with the first heat source 1 then with the second heat source 2 by means of one or more displacer(s). This or these displacer(s) function as free pistons whose stop-type position is determined solely by the pressure difference between the first and second heat transfer fluid supply circuits A, B and C, D.

[0057] Preferably, said first pressure and / or flow rate regulating member and / or said second pressure and / or flow rate regulating member and / or said third pressure and / or flow rate regulating member of the first heat transfer fluid supply circuit A, B and / or the fourth pressure regulating member of the second heat transfer fluid supply circuit C, D is chosen from a pressure limiter 26, 27 and / or a flow regulator 28, 29 and / or a hydraulic valve and / or an adjustable flow limiter and / or a variable throttle orifice or an additional pressure accumulator.

[0058] The second control unit preferably comprises at least one pressure sensor 22, 23, 24, 25. The pressure sensor 22, 23 can be connected to the working fluid supply circuit J, H. Alternatively, the pressure sensor 24, 25 can be connected to the first supply circuit A, B or to the second supply circuit C, D. The second control unit can also comprise a temperature sensor 37, 38 which can be connected to the first supply circuit A, B or to the second supply circuit C, D.

[0059] Preferably and as illustrated by the figures 3 And 4, said thermal machine comprises at least a first module 3, 3' and a second module 3, 3', which are connected in series to each other at their thermodynamic fluid supply outlet G or their hydraulic fluid supply outlet E using a first interconnection pipe 31, which are connected in series to each other at their first supply circuit A, B, and which are connected in series to each other at their second supply circuit C, D.

[0060] Preferably, said first control unit is arranged at least to centrally control the phase in which the thermodynamic cycle is located in said first module 3, 3' and in said second module 3, 3'.

[0061] Alternatively, said second control unit is common to the first module 3, 3' and to the second module 3, 3' and is arranged to centrally control said at least one displacer of the first module 3, 3' and said at least one displacer of the second module 3, 3'.

[0062] As illustrated by the figures 8 à 11 , said thermal machine comprises at least one first module 32 and at least one second module 33, which are each connected to the first conversion unit 6 by their thermodynamic fluid supply outlet G or by their hydraulic fluid supply outlet E and the first module 32 and the second module 33 are arranged so that when said at least one displacer of the first module 32 is in the cold part 4 then said at least one displacer of the second module 33 is in the hot part 5.

[0063] Advantageously, this configuration is said to be in phase opposition. The examples illustrated below in the figures 8 à 11 are distinguished by the management of energy from the isobaric heating phase 2-3. This management depends on the conversion system installed (hydraulic motor mapping, inertia size). It is therefore interesting to be able to modulate this energy to supply the hydraulic motor 12 in its best efficiency zone.

[0064] In a first example illustrated in the figure 8 , the first conversion unit 6 and the second conversion unit 18 are substantially identical to those of the first embodiment variant illustrated in figure 3 . The thermal machine makes it possible to heat at least one first module 32 forming an assembly A while cooling at least one second module 33 forming an assembly B to avoid working with hydraulic pressure accumulators 11 of excessively large dimensions. The hydraulic fluid thus passes from said at least one first module 32 to said at least one second module 33. In this case, the pressure accumulator 11 then only plays a buffer storage role, the thermodynamic fluid not necessarily contracting at the same rate as it expands on the opposite side. The equilibrium detection of said at least one second module 33 is carried out for example using a flow meter 34. Four non-return valves 35 form a passive system for managing the flows between said at least one first module 32 and said at least one second module 33.

[0065] Advantageously, in the first example of the figure 8 , the energy of the isobaric heating phase 2-3 is not stored and feeds the hydraulic motor 12 directly upon opening the adjustable pressure limiter 16 at the pressure of point 2 of the cycle. There is no feed flow control of the hydraulic motor 12.

[0066] In a second example illustrated in the figure 9 , the addition of an additional pressure accumulator 30 in the high pressure part after the hydraulic valve 15 can make it possible to smooth the flow of fluid supplying the motor 8 during polytropic expansion in order to operate the latter in its best efficiency range. The pressure accumulator 11 is precharged at least to the critical pressure of the thermodynamic fluid.

[0067] Advantageously, in the second example of the figure 9 , the energy of the isobaric heating phase 2-3 is partially stored in an additional pressure accumulator 30 in order to smooth the flow supplying the hydraulic motor 12 during this phase.

[0068] In a third example illustrated in the figure 10 , an additional pressure accumulator 30 is selected, sized to be able to store all of the energy during the isobaric heating phase 2-3, in this case it is possible to simplify by placing the additional pressure accumulator 30 before the hydraulic valve 15, which makes it possible to eliminate the adjustable pressure limiter 16. When the hydraulic valve 15 opens, the energy from the isobaric heating and then from the preferably polytropic expansion is then restored. The inertia 19 then determines the expansion time.

[0069] 35 check valves can be simple ( figures 8 et 9 ) or tared ( figure 10 ).

[0070] Advantageously, in the third example of the figure 10 , the energy of the isobaric heating phase 2-3 is fully stored in an additional pressure accumulator 30 then returned at the start of the expansion phase 3-4.

[0071] This management of the energy from the isobaric phase 2-3 is a significant advantage. Indeed, the energy of the thermodynamic cycle is recovered during two phases, the isobaric heating phase and the preferably polytropic expansion. However, the times of these two phases can be very different, the expansion phase being faster than the isobaric heating phase. The flow rates supplying the motor 8 can therefore vary greatly from one phase to the other. However, for example, the hydraulic motors 12 maintain good efficiency in defined flow rate ranges which can be lower than the actual flow rate variations of the cycle. This is why, in the examples, figures 9 And 10a "smoothing" of this energy, by means of a partial or total storage of the energy of the isobaric heating phase in an additional pressure accumulator 30 placed before or after the pressure and / or flow regulating element 13 (hydraulic valve 15). It is thus possible to modulate the supply flow of the engine 8 to remain in its high efficiency range. The order of magnitude of the time to carry out a complete thermodynamic cycle varies greatly depending on the temperature difference between the first and second heat sources 1, 2 but is between a few seconds to a few tens of seconds. The thermodynamic cycle is carried out without a mechanical compressor.

[0072] In a fourth example illustrated in the figure 11 , the configuration is similar to that of the figure 4 A 36 4 / 2 distributor can also fulfill the role of managing the flows between the different sets A and B but needs to be controlled (active system), unlike the four non-return valves 35 described previously.

[0073] The operation of the third example illustrated in the figure 10 is explained below in relation to the figures 12 à 17 . As illustrated by the figure 12 , said at least one first module 32 of the assembly A is heated in the isochoric heating phase 1-2 and said at least one second module 33 of the assembly B is cooled in the cooling phase 4-1. The coupling 20 is uncoupled. The hydraulic valve 15 is closed. The additional pressure accumulator 30 is closed as long as the pressure is lower than the precharge pressure of the additional pressure accumulator 30. This phase is completed when the pressure in said at least one first module 32 of the assembly A is equal to the precharge pressure of the additional pressure accumulator 30.

[0074] As illustrated by the figure 13 , said at least one first module 32 of the set A is heated in the isobaric heating phase 2-3 and said at least one second module 33 of the set B is cooled in the cooling phase 4-1. The hydraulic valve 15 is closed. The additional pressure accumulator 30 is open and stores the energy coming from the isobaric heating phase 2-3. The flow meter 341 allows the detection of the end of this heating phase.

[0075] As illustrated by the figure 14 , said at least one first module 32 of the assembly A is in the expansion phase 3-4 and said at least one second module 33 of the assembly B is cooled in the cooling phase 4-1. The hydraulic valve 15 is open. The additional pressure accumulator 30 restores the stored energy. The rotation speed sensor 10 makes it possible to detect the end of the expansion phase. The flow meter 342 makes it possible to detect the end of this cooling phase. The coupling 20 is coupled and the mechanical energy is transformed into electricity. When the expansion and the cooling are finished, the hydraulic valve 15 is closed and said at least one displacer of said at least one first module 32 and said at least one displacer of said at least one second module 33 are reversed by differential pressure inversion, as described previously using the second control module.

[0076] As illustrated by the figure 15 , said at least one first module 32 of the assembly A is cooled in the cooling phase 4-1 and said at least one second module 33 of the assembly B is heated in the isochoric heating phase 1-2. The hydraulic valve 15 is closed. The coupling 20 is decoupled. The additional pressure accumulator 30 is closed as long as the pressure is lower than the precharge pressure of the additional pressure accumulator 30. This phase is completed when the pressure in said at least one second module 33 of the assembly B is equal to the precharge pressure of the additional pressure accumulator 30.

[0077] As illustrated by the figure 16 , said at least one first module 32 of the set A is cooled in the cooling phase 4-1 and said at least one second module 33 of the set B is heated in the isobaric heating phase 2-3. The hydraulic valve 15 is closed. The additional pressure accumulator 30 is open and stores the energy coming from the isobaric heating phase 2-3. The flow meter 341 allows the detection of the end of this heating phase.

[0078] As illustrated by the figure 17 , said at least one first module 32 of the assembly A is cooled in the cooling phase 4-1 and said at least one second module 33 of the assembly B is in the expansion phase 3-4. The hydraulic valve 15 is open. The additional pressure accumulator 30 restores the stored energy. The rotation speed sensor 10 and / or the pressure sensor 9, 90 associated with the assembly B makes it possible to detect the end of the expansion phase. The flow meter 342 and / or the pressure sensor 9, 90 associated with the assembly A makes it possible to detect the end of this cooling phase. The coupling 20 is coupled and the mechanical energy is transformed into electricity.When the expansion and cooling are complete, the hydraulic valve 15 is closed and said at least one displacer of said at least one first module 32 and said at least one displacer of said at least one second module 33 are reversed by differential pressure inversion, as described previously using the second control module.

[0079] Advantageously, the sequencing proposed and explained in relation to the figures 12 à 17 and allows the evolution of the phases to be followed in a so-called phase opposition architecture, that is to say that set A is heated and set B is cooled or vice versa and two volumes of thermodynamic fluids follow opposite phases at each instant.

[0080] The inversion of the movers within the modules is done according to the description in relation to the figures 5 à 7 .

[0081] A certain number of elements have a "passive" operation, thus simplifying the control of the thermal machine as much as possible. For example, the non-return valves 35 make it possible to supply the hydraulic motor 12 always in the same direction by forming a circuit managed solely by the induced pressure differences. The coupling 20, ideally of the freewheel type, does not require any particular action and transmits energy to the inertia only in the direction of rotation of the hydraulic motor 12, while remaining decoupled if the hydraulic motor 12 rotates less quickly than the inertia 19. The additional pressure accumulator 30 is calibrated to an opening pressure of point 2 of the cycle, allowing isochoric heating as long as the pressure is lower than the pressure at point 2 of the cycle.

[0082] The first control unit only requires the use of two flow meters 34, 341, 342 and / or two pressure sensors 9, 90 in order to determine the ends of the heating and cooling phases.

[0083] One of the characteristics of phase-opposed architectures as illustrated in figure 9 is that a set A, B can chain the first three phases of the cycle [1-2, 2-3, 3-4] independently of the other set B, A which is only in the cooling phase [4-1] The inversion of the displacers only occurs when the two sequences are finished, [1-2, 2-3, 3-4] on one side and [4-1] on the other, but it is not determined that the cooling [4-1] is systematically longer or shorter than the succession of phases [1-2, 2-3, 3-4] The order of magnitude of the time necessary for the two sequences is however quite close in the temperature and pressure range targeted, which avoids downtime in the use of the machine.

[0084] This optimization logic only applies to phase-opposed architectures. For simple architectures such as figure 3 , only cycle optimization is possible.

[0085] There figure 19 represents an example of module 3 according to the invention for the displacement of a thermodynamic fluid alternately between a cold part 4 connected to a first heat source 1 and a hot part 5 connected to a second heat source 2 for a thermodynamic cycle thermal machine.

[0086] This module 3 generally comprises at least one cartridge 101 or a plurality of cartridges 101, in the example of the figure 19 , a single cartridge 101 described below is included, and further comprises:

[0087] the first heat transfer fluid supply circuit A, B connected to first circulation means 103 of said at least one cartridge 101 by at least one first supply orifice 135 and at least one second supply orifice 136 of the first circulation means 103,

[0088] a second heat transfer fluid supply circuit C, D connected to second circulation means 109 of said at least one cartridge 101 by at least one third supply orifice 137 and at least one fourth supply orifice 138 of the second circulation means 109,

[0089] a junction plate 139 comprising at least junction means 114 of the cartridge 101,

[0090] a working fluid supply circuit H, J, connected to a third profile 115 of said at least one cartridge 101 by at least one fifth supply orifice 140 which the third profile 115 comprises and at least one sixth supply orifice 141 which the third profile 115 comprises, arranged to control the movement of the piston 126,

[0091] a thermodynamic fluid supply outlet G connected to the chamber 124 of said at least one cartridge 101 or a hydraulic fluid supply outlet E connected to a first filling space 121 or to a second filling space 123 of said chamber 124.

[0092] Preferably and as illustrated by the figure 19 , the working fluid supply circuit H, J is formed of said first heat transfer fluid supply circuit A, B and said second heat transfer fluid supply circuit C, D.

[0093] Preferably and as illustrated by the figure 19 , the module 3 comprises a first insulating enclosure 143 which comprises at least one first compartment 144 into which said at least one first supply orifice 135 of the first circulation means 103 opens and at least one second compartment 145 into which said at least one second supply orifice 136 of the first circulation means 103 opens.

[0094] Preferably additionally or alternatively and as illustrated in figure 19 , the module 3 comprises a second insulating enclosure 143' which comprises at least one third compartment 146 into which said at least one third supply orifice 137 of the second circulation means 109 opens and at least one fourth compartment 147 into which said at least one fourth supply orifice 138 of the second circulation means 109 opens.

[0095] The first compartment 144 and the second compartment 145 are preferably delimited by at least one first separating wall 148.

[0096] The third compartment 146 and the fourth compartment 147 are preferably delimited by at least one second separating wall 149.

[0097] As illustrated by the figure 19 , a cartridge 101 for moving a thermodynamic fluid between a cold part 4 connected to a first heat source 1 and a hot part 5 connected to a second heat source 2 for a thermodynamic cycle thermal machine comprises at least: a first exchanger, forming a so-called cold part 4, comprising a first hollow profile 102 comprising first circulation means 103 of at least one heat transfer fluid suitable and intended to be connected to a first heat transfer fluid supply circuit A, B connected to a first heat source, said first profile 102 comprising an internal wall and an external wall, a second exchanger, forming a so-called hot part, comprising a second hollow profile 108 comprising second circulation means 109 of at least one heat transfer fluid suitable and intended to be connected to a second heat transfer fluid supply circuit C, D connected to a second heat source, said second profile 108 comprising an internal wall and an external wall, a third hollow profile 115 suitable and intended to be connected to at least one supply circuit of at least one working fluid J, H,said third profile 115 being arranged inside the first profile 102 and the second profile 108, said third profile 115 comprising an inner wall and an outer wall, at least a portion of the inner wall of the first profile 102 and a first portion of the outer wall of the third profile 115 being spaced apart and located opposite each other so as to form a first filling space 121, at least a portion of the inner wall of the second profile 108 and a second portion of the outer wall of the third profile 115 being spaced apart and located opposite each other so as to form a second filling space 123, at least one chamber 124 capable and intended to contain at least one thermodynamic fluid preferably at high pressure and in the supercritical state, said chamber 124 comprising at least the first filling space 121 and the second filling space 123 which are communicating,at least one displacer 125 disposed inside said chamber 124 and mounted to slide relative to the external wall of said third profile 115 and movable between a first position and a second position, and configured to alternately move said at least one thermodynamic fluid between the first filling space 121 and the second filling space 123, a piston 126 disposed inside said third profile 115 and mounted to slide relative to the internal wall of said third profile 115 and movable between the first position and the second position, the piston 126 being capable and intended to be moved by said at least one working fluid J, H between the first position and the second position, the displacer 125 and the piston 126 being coupled to each other.

[0098] Preferably, the third profile 115 is preferably made of non-magnetic material and the displacer 125 and the piston 126 are magnetically coupled to each other through the third profile 115 by magnetic connection means 127.

[0099] Advantageously, this configuration allows control of the displacer 125 from outside the chamber 124 by means of a magnetic coupling between the piston 126 and the displacer 125. This magnetic coupling makes it possible to transmit axial forces to the displacer 125 without mechanical contact and therefore without friction. This avoids causing prohibitive losses and wear due to friction. This arrangement thus helps to limit losses.

[0100] Non-magnetic means a material which does not have magnetic properties or whose magnetic permeability is low, i.e. for example close to 1 and generally less than 50.

[0101] Preferably and as illustrated by the figure 19 , said third profile 115, said first profile 102 and said second profile 108, the displacer 125 and the piston 126 are coaxial.

Claims

1. Heat engine adapted and designed to perform at least one conversion of thermal energy into mechanical energy comprising at least one thermodynamic fluid and adapted and designed to implement a thermodynamic cycle comprising at least one isochoric heating phase, optionally an isobaric heating phase, an expansion phase and an isobaric cooling phase, the heat engine comprising at least : - a first heat source (1) at a first temperature T1 configured to contain and transmit thermal energy to at least one heat transfer fluid, - a second heat source (2) at a second temperature T2 configured to contain and transmit thermal energy to at least one heat transfer fluid, the first and second temperatures T1 and T2 being different, - at least one module (3, 3') for moving the thermodynamic fluid alternately between a cold part (4) connected to the first heat source (1) and a hot part (5) connected to the second heat source (2), said at least one module (3, 3') comprising at least the cold part (4), said at least one module (3, 3') comprising a first heat transfer fluid supply circuit (A, B) connected to the first heat source (1) and to the cold part (4), said at least one module (3, 3') comprising at least the hot part (5), said at least one module (3, 3') comprising a second heat transfer fluid supply circuit (C, D) connected to the second heat source (2) and to the hot part (5), said at least one module (3, 3') comprising at least one chamber suitable and designed to contain said at least one thermodynamic fluid and which is connected to at least one thermodynamic fluid supply outlet (G) at a first pressure P1 or to a hydraulic fluid supply outlet (E) at a second pressure P2, - at least one first conversion unit (6) for converting a pressure difference of the thermodynamic fluid into mechanical energy comprising at least one circuit (7) which comprises at least mechanical conversion means, preferably a motor (8), said first conversion unit (6) being connected to the thermodynamic fluid supply outlet (G) or to the hydraulic fluid supply outlet (E), at least a first control unit at least partly disposed in the first conversion unit (6) arranged at least to control the phase in which the thermodynamic cycle is in said at least one module (3, 3'), said heat engine is characterized in that said at least one module (3, 3') further comprises at least one displacer movable in said chamber alternately between the cold part (4) and the hot part (5), said chamber being suitable and intended to contain said at least one high-pressure thermodynamic fluid having pressures between 50 bar and 300 bar and in the supercritical state, and in that it comprises a second control unit of said at least one module (3, 3') arranged to control the displacement of said at least one displacer alternately between the hot part (5) and the cold part (4).

2. Heat engine according to claim 1, characterized in that said first conversion unit (6) comprises at least one pressure accumulator (11) connected downstream of the mechanical conversion means, preferably of the motor (8), which is a hydraulic motor (12) or a turbine with thermodynamic fluid (14) preferably in the supercritical state, said pressure accumulator (11) being able and intended to maintain or vary the pressure of the circuit (7) greater than or equal to the critical pressure of the thermodynamic fluid.

3. Heat engine according to claim 2, characterized in that said first control unit comprises at least one pressure and / or flow measuring member (9) arranged to control the phase in which the thermodynamic cycle is, and in particular to determine the completion of each phase of the cycle, said pressure and / or flow rate measuring member (9) being disposed between the chamber and said pressure accumulator (11) and preferably being disposed between the thermodynamic fluid supply outlet (G) or the hydraulic fluid supply outlet (E) and said pressure accumulator (11).

4. Heat engine according to claim 3, characterized in that said first control unit comprises at least one pressure and / or flow regulation element (13) of the circuit (7) arranged at least to control / pilot the isobaric heating phase and / or the expansion phase of the thermodynamic cycle, said at least one pressure and / or flow regulation element (13) being arranged between the thermodynamic fluid supply outlet (G) or the hydraulic fluid supply outlet (E) and said pressure accumulator (11).

5. Heat engine according to any one of claims 1 to 4, characterized in that it further comprises a second mechanical-to-electrical energy conversion unit (18) connected to said first conversion unit (6) downstream of the mechanical conversion means, preferably of said motor (8).

6. Heat engine according to claim 5, characterized in that the second conversion unit (18) comprises at least one inertia (19) connected on the one hand to a coupling (20) and on the other hand to a generator (21).

7. Heat engine according to any one of claims 1 to 6, characterized in that the module (3, 3') comprises at least one piston contained in a cylinder connected to a working fluid supply circuit (J, H) via a first end and a second end of the cylinder for controlling the displacement of the piston movable in the cylinder and in that the displacer and the piston are coupled to each other.

8. Heat engine according to claim 7, characterized in that the second control unit comprises at least one first pressure and / or flow regulating member at the first end of the cylinder and at least one second pressure and / or flow regulating member at the second end of the cylinder for maintaining or varying a pressure difference between the first end and the second end so as to displace said at least one displacer alternately between the hot part (5) and the cold part (4).

9. Heat engine according to claim 7, characterized in that the working fluid supply circuit (J, H) is formed by said first heat transfer fluid supply circuit (A, B) and said second heat transfer fluid supply circuit (C, D), and in that the second control unit comprises at least a first member for regulating the pressure and / or flow rate of the first heat source (1) and a second member for regulating the pressure and / or flow rate of the second heat source (2), the first pressure and / or flow-rate regulator and the second pressure and / or flow-rate regulator being configured to maintain or vary a pressure difference between the first heat source (1) and the second heat source (2) so as to displace said at least one displacer alternately between the cold part (4) and the hot part (5).

10. Heat engine according to any one of claims 3 to 9, characterized in that said pressure and / or flow regulating element (13) and / or said first pressure and / or flow regulating member and / or said second pressure and / or flow regulating member and / or said third pressure and / or flow regulating member of the first heat transfer fluid supply circuit (A, B) and / or the fourth pressure regulator of the second heat transfer fluid supply circuit (C, D) is selected from a pressure limiter (16, 26, 27) and / or a flow regulator (28, 29) and / or a hydraulic valve (15) and / or an adjustable flow limiter and / or a variable throttle orifice (17) or an additional pressure accumulator (30).

11. Heat engine according to claim 3, characterized in that said pressure and / or flow measuring member (9) of the circuit (7) is chosen from at least one pressure sensor (90) or flowmeter or rotational speed sensor (10) or linear displacement sensor of a hydraulic piston.

12. Heat engine according to any one of claims 1 to 11, characterized in that said heat engine comprises at least a first module (3, 3') and a second module (3, 3'), which are connected in series to each other at their thermodynamic fluid supply outlet (G) or their hydraulic fluid supply outlet (E) by means of a first interconnecting line (31), which are connected in series with each other at their first supply circuit (A, B), and which are connected in series with each other at their second supply circuit (C, D).

13. Heat engine according to the preceding claim, characterized in that said first control unit is arranged at least to centrally control the phase in which the thermodynamic cycle is in said first module (3, 3') and in said second module (3, 3').

14. Heat engine according to claim 11, characterized in that said second control unit is common to the first module (3, 3') and the second module (3, 3') and is arranged to centrally control said at least one displacer of the first module (3, 3') and said at least one displacer of the second module (3, 3').

15. Heat engine according to any one of claims 1 to 14, characterized in that said heat engine comprises at least one first module (32) and at least one second module (33), which are each connected to the first conversion unit (6) via their thermodynamic fluid supply outlet (G) or via their hydraulic fluid supply outlet (E), and in that the first module (31) and the second module (33) are arranged so that when said at least one displacer of the first module (31) is in the cold part (4) then said at least one displacer of the second module (33) is in the hot part (5).

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