Turbine engine for an aircraft and method for cooling a turbine engine

Abstract

The present invention relates to a turbine engine (2) for an aircraft, the turbine engine comprising: - an annular flow path (V) for airflow (F3); - a motor (M); - at least one device (E); - a first ACOC type heat exchanger (210) capable of being swept by airflow (F3) and including a first oil circuit (C1) connected to a cooling system (S1) for the motor; - a second ACOC type heat exchanger (220) capable of being swept by airflow (F3) and including a second oil circuit (C2) connected to a cooling system (S2) for cooling at least one device (E); and - a third OCOC type heat exchanger (230) including a third oil circuit and a fourth oil circuit (C3, C4) capable of exchanging heat energy with each other.

Description

Technical Field

[0001] The present invention relates to a turbine engine for an aircraft and a method for cooling the turbine engine. Background Technology

[0002] The technical background specifically includes documents US-A1-2012 / 085528, US-A1-2023 / 332543, US-A-4,696,156 and US-A1-2010 / 212857.

[0003] Turbine engines used in aircraft include various components and / or equipment that require lubrication and / or cooling, such as rolling bearings and gears. Additionally, next-generation turbine engines include onboard electric motors for hybrid power systems, which require oil lubrication and cooling. The heat generated by these components is transferred by oil and dissipated to available onboard cooling sources.

[0004] The cooling sources on the engine include air and fuel. The fuel can first be cooled by the fuel in a fuel / oil exchanger (often called a Fuel Cooled Oil Cooler (FCOC)), which also heats the fuel before it enters the combustion chamber. The FCOC heat exchanger is insufficient to absorb all the heat loss because fuel temperature is limited by safety constraints. Additional cooling can be provided through an air / oil exchanger (often called an Air Cooled Oil Cooler (ACOC)).

[0005] Air constitutes the cold source for cooling the oil, and can originate from the secondary flow path, for example, in the case of a two-flow turbine engine, or from the tertiary flow path, for example, in the case of a three-flow turbine engine. Figure 1 As shown in the figure and described in document WO-A1-2023 / 099533.

[0006] Due to the significant increase in heat dissipation, ACOC switches will be increasingly used in next-generation motors, primarily because: Future motors will be larger, which will increase the demand for lubrication and oil cooling; - The new motor design includes a speed reducer that transmits very high mechanical power and requires oil lubrication and cooling. - Adding electric motors to the main motor to create hybrid power systems requires oil for lubrication and cooling.

[0007] A motor may include multiple oil circuits, each with a defined function, such as a first circuit for cooling the oil used to lubricate and cool the motor, a second circuit for lubricating and cooling the motor, etc.

[0008] Oil temperature and flow rate must be controlled according to the corresponding circuit. For example, the oil used for lubricating and cooling an electric motor has a different temperature range than the oil used for motor cooling. ACOC heat exchangers are preferably divided into multiple exchangers, each dedicated to a given oil circuit. These different exchangers are installed in parallel in one of the flow paths of the turbine engine and occupy a portion of that flow path.

[0009] exist Figure 2 In this configuration, ACOC heat exchanger 1 can be used to cool the motor cooling oil. ACOC heat exchanger 2 can be used to cool the oil in a hybrid electric motor used in a turbine engine.

[0010] Each of ACOC1 and ACOC2 occupies a given angular sector of the flow path. The flow path V is defined by coaxial annular walls 101 and 102, which are connected together by structural arms 100 to ensure mechanical strength. The angular sector, denoted by "A", is the sector in which air flows without any obstructions (no ACOC exchangers).

[0011] The size of each of the two switches must be suitable for the maximum case in order to dissipate heat dissipation power in all other flight phases.

[0012] exist Figure 3 In the ACOC heat exchanger 1, it is divided into two parts: - Part 1a: Part of ACOC exchanger 1, used to cool the motor oil during all flight phases except the most critical phase. - Part 1b: A part of ACOC exchanger 1, added to part 1a to provide additional cooling during the most demanding flight phases (e.g., when the aircraft is on the ground on a very hot day).

[0013] exist Figure 3 In the ACOC heat exchanger 2, it is divided into two parts: - Part 2a: Part of ACOC exchanger 2, used to cool the motor oil during all flight phases except the most demanding phases, and - Part 2b: Part of ACOC exchanger 2, added to part 1a to provide additional cooling during the most demanding flight phases.

[0014] The two ACOC exchangers (ACOC1 and ACOC2) perform different cooling functions. This results in different dimensional phases for each of the two exchangers, and leads to excessive exchanger size under other phases and flight conditions, which directly affects the pressure drop on the air side (aerodynamic thermal performance) and the mass of the exchangers. This has the effect of increasing the specific fuel consumption (SFC) of the turbine engine and thus increasing its fuel consumption rate (Fuel Burn, FB).

[0015] Therefore, it is necessary to optimize the aerodynamic and thermal performance of these exchangers.

[0016] The solution proposed in EP-A1-2472067 presents an ACOC heat exchanger embedded in the compartment of a turbine engine. The heat exchanger is integrated into a cavity on the radially inner wall leading to the secondary flow path. A portion of the secondary airflow taken from the secondary flow path passes through the embedded heat exchanger, where it is reheated and reinjected into the secondary flow path. A controlled scoop-shaped element, for example, formed by a pivotable and / or translationally movable baffle, is positioned at the inlet of the cavity to extend into the secondary flow path and provide an adjustable airflow toward the embedded heat exchanger. When the movable baffle of the scoop-shaped element is open, it can create a pressure drop in the secondary flow path. When heat exchange in the embedded heat exchanger is not required, the movable baffle is actuated to close.

[0017] Patent WO-A1-2022 / 123168A1 discloses a solution for optimizing the aerodynamic and thermal performance of an exchanger in a cavity and reducing pressure drop by connecting a movable baffle to a movable member adaptable to different flight phases of a turbine engine and an aircraft. This patent relates to a heat exchange system for a turbine engine, comprising a cavity including an air inlet, a heat exchanger disposed within the cavity and including a first circuit through which a first fluid can flow, a movable baffle mounted on the air inlet and movable between two positions that respectively allow or prevent air flow within the cavity, and a control device including a movable member configured to drive movement of the movable baffle. The control device is disposed in a supply circuit for supplying the exchanger and is configured to allow or prevent the first fluid from flowing toward the exchanger, and simultaneously acts on one of the two positions of the movable baffle.

[0018] This invention provides a simple, effective, and economical solution to the problems and needs of the prior art. Summary of the Invention

[0019] This invention relates to a turbine engine for an aircraft, the turbine engine comprising: - A circular flow path for airflow. -motor, -At least one device, - A first ACOC type heat exchanger, the first ACOC type heat exchanger being capable of being swept by the airflow and including a first oil circuit, the first oil circuit being connected to a cooling system for cooling the motor. - A second ACOC-type heat exchanger, the second ACOC-type heat exchanger being capable of being swept by the airflow and including a second oil circuit, the second oil circuit being connected to a cooling system for cooling the at least one device. The turbine engine is characterized in that it further includes: - A third OCOC type heat exchanger, the third OCOC type heat exchanger comprising a third oil circuit and a fourth oil circuit capable of exchanging heat energy between them, and - A connecting valve that connects the first circuit to the third circuit and the second circuit to the fourth circuit; the connecting valve can be configured in two ways: - First configuration, wherein the third loop is isolated from the first loop, and the fourth loop is isolated from the second loop, and - Second configuration, wherein a third circuit is connected in series with a first circuit to supply oil to the first circuit via the third circuit, and a fourth circuit is connected in series with a second circuit to supply oil to the second circuit via the fourth circuit.

[0020] In this application, ACOC exchanger refers to air / oil exchanger, ACOC is an abbreviation for "Air-Cooled Oil Cooler", and OCOC refers to oil / oil exchanger, OCOC is an abbreviation for "Oil-Cooled Oil Cooler".

[0021] The present invention proposes the use of an oil / oil cooler (OCOC) that provides heat exchange between oil in a first circuit of a first exchanger and oil in a second circuit of a second exchanger.

[0022] This solution applies even if the cooling oils in the first and second exchangers are of different types. Since the oils from the first and second exchangers flow in a separate loop within the third exchanger, there is no risk of these oils mixing in the third exchanger.

[0023] This invention allows for the determination of the dimensions of a first heat exchanger to ensure oil cooling for all flight phases except the most critical phases, and the addition of a third heat exchanger to ensure additional oil cooling for the critical phases of the first heat exchanger. This third heat exchanger is shared by both the first and second heat exchangers. The dimensions of the second heat exchanger are designed to withstand all relevant flight conditions, including the most critical conditions for cooling one or more devices.

[0024] Given that the first and second exchangers are not in phase, a third exchanger can be used to provide additional cooling for the first exchanger's maximum phase by ensuring exchange between the oil in the first and second exchangers. This allows a portion of the heat power from the oil in the first exchanger to be transferred to the oil in the second exchanger via the third exchanger. Some of the heat power generated by the oil in the first exchanger will be dissipated in the second exchanger. This is quite feasible considering that the second exchanger does not operate at its maximum dissipation, as the maximum phase of the first exchanger typically does not correspond to the maximum phase of the second exchanger.

[0025] Compared to the reference case, the present invention enables a reduction in the size of the first switch and thus a reduction in voltage drop. The size of the second switch can remain unchanged from the reference case.

[0026] Heat power is typically transferred from high temperature to low temperature, that is, from the first exchanger to the second exchanger.

[0027] The turbine engine according to the invention may include one or more of the following features, either individually or in combination thereof; these features have the particular advantage of optimizing the compactness of the geared motor unit: - In the second configuration, the outlet of the third loop is connected to the inlet of the first loop, and the outlet of the fourth loop is connected to the inlet of the second loop; - The first circuit includes a first inlet valve connected to the inlet of the first circuit, and the second circuit includes a second inlet valve connected to the inlet of the second circuit; - The connection valve includes: - A first connecting valve, installed between the connection point of the inlet of the first circuit located upstream of the first inlet valve and the inlet of the third circuit, and - A second connecting valve is installed between the connection point of the inlet of the second circuit located upstream of the second inlet valve and the inlet of the fourth circuit; - The third circuit includes an outlet connected to another connection point of the inlet of the first circuit located downstream of the first inlet valve, and the fourth circuit includes an outlet connected to another connection point of the inlet of the second circuit located downstream of the second inlet valve; - The third heat exchanger is located outside the flow path; - The first heat exchanger has an angular sector shape and occupies only a portion of the angular range of the flow path; this integration model ensures better integration of one or more exchangers in the flow path and reduces pressure drop on the airflow side, while also optimizing aerodynamic thermal performance. -The first heat exchanger has an angle range between 30° and 90°; - The second heat exchanger has an angular sector shape and occupies only a portion of the angular range of the flow path; - The second heat exchanger has an angle range between 30° and 90°; - The first and second heat exchangers are passed through the same plane perpendicular to the longitudinal axis of the turbine engine; - A portion of the angular range of the flow path is free and therefore not occupied by one or more switches, particularly the first and second switches; - The flow path is a secondary flow path for the flow of secondary airflow, and the turbine engine also includes a primary flow path for the flow of primary airflow inside the motor. - The flow path is a third-stage flow path for the flow of the third-stage airflow. The turbine engine also includes two annular flow paths for the flow of the primary and secondary airflows, namely the primary flow path and the secondary flow path. The use of this third flow path provides additional cooling during certain operating phases of the turbine engine because the flow path has a reduced cross-section and is more sensitive to aerodynamic losses; therefore, the annular integration provides these benefits. - The tertiary flow path is radially located between the primary flow path and the secondary flow path; - The tertiary flow path is circular; - The cooling capacity of the third heat exchanger is lower than that of the first heat exchanger and also lower than that of the second heat exchanger; -The at least one device includes a motor; - The motor is a gas generator.

[0028] The present invention also relates to a cooling method for a turbine engine as described above, wherein the cooling method comprises two steps corresponding to the two configurations described above: - Corresponding to the first step of the first configuration, wherein the cooling system for cooling the motor is supplied with oil exiting the first exchanger, and the cooling system for cooling the at least one device is supplied with oil exiting the second exchanger, and - A second step corresponding to the second configuration, wherein the cooling system for cooling the motor is supplied with oil that passes through the third exchanger and then through the first exchanger, and the cooling system for cooling the at least one device is supplied with oil that passes through the third exchanger and then through the second exchanger.

[0029] The method according to the invention may include one or more of the following features or steps, employed independently or in combination with each other: - The second step occurs when the aircraft is on the ground and the external ambient temperature is higher than a predetermined threshold. - The first step is the default step in all other cases; - The first heat exchanger is supplied with oil at a maximum temperature of 180°C, and the second heat exchanger is supplied with oil at a maximum temperature of 100°C. Attached Figure Description

[0030] Other features and advantages will become apparent from the following description of non-limiting embodiments of the invention with reference to the accompanying drawings, in which: [ Figure 1 ] Figure 1 It is a schematic axial cross-sectional view of a turbine engine used in aircraft; [ Figure 2 ] Figure 2 This is a very schematic cross-sectional view of the flow path used for airflow, in which the heat exchanger is located. [ Figure 3 ] Figure 3 Is with Figure 2 A similar view, showing a breakdown of the heat exchanger. [ Figure 4 ] Figure 4 This is a schematic cross-sectional view of the flow path for the airflow and three heat exchangers, and illustrates one embodiment of the invention. [ Figure 5 ] Figure 5 yes Figure 4 A very schematic view of the three heat exchangers is shown, along with a first configuration of the connecting valves that connect the exchangers. [ Figure 6 ] Figure 6 Is with Figure 4 A similar view is shown, and a second configuration of the connecting valve for connecting the exchanger is also shown. Detailed Implementation

[0031] Figure 1 A turbine engine 2 for an aircraft is shown. This turbine engine 2 illustrates the prior art described in document WO-A1-2023 / 099533, but can be used to describe the installation environment of the present invention.

[0032] The turbine engine 2 moves in the airflow F, the motion of which relative to the turbine engine 2 is generated by the rotation of the propeller 4 and the forward motion of the aircraft on which the turbine engine 2 is mounted.

[0033] The airflow F is divided by the first splitter nose 10 into a radially internal airflow F' and a radially external airflow F2 (referred to as the secondary flow F2). The propeller 4 can be located upstream or downstream of the first splitter nose 10.

[0034] The radial internal airflow F' passes through the movable wheel 12, which guides the radial internal airflow F' toward the second splitter nose 14, which can divide the radial internal airflow F' into a main flow F1 and a tertiary flow F3, which is different from the secondary flow F2.

[0035] The first splitter nose 10 includes an inner wall that forms a first outer guide wall 11 for guiding a radially internal airflow F'. Viewed from the radially internal airflow F', the first outer guide wall 11 forms a convex profile.

[0036] The second splitter nose 14 includes an outer wall that forms a second outer guide wall 13 for guiding the radially internal airflow F' that has passed through the movable wheel 12. From the perspective of the tertiary flow F3, the second outer guide wall 13 forms a convex profile.

[0037] The tertiary flow F3 enters the tertiary flow path 16 radially outside the main flow F1. The tertiary flow F3 passes through the heat exchanger 18 located in the tertiary flow path 16.

[0038] The turbine engine 2 is shown symmetrical about the longitudinal axis 8. The tertiary flow path 16 is annular and continuous 360° around the longitudinal axis 8. Therefore, the tertiary flow F3 is annular through the tertiary flow path 16.

[0039] In this configuration, the tertiary flow F3 extends substantially along the axial direction and is located radially between the main flow F1 and the secondary flow F2.

[0040] The tertiary flow F3 extends from the radially internal airflow F' downstream of the movable wheel 12 in the tertiary flow path 16 and extends to the secondary flow F2 after passing through the heat exchanger 18.

[0041] The turbine engine 2 also includes a stator (not shown) arranged upstream of the heat exchanger 18 at the third-stage flow path 16. Advantageously, the stator allows the third-stage flow F3 to be rectified before it passes through the heat exchanger 18, thereby minimizing aerodynamic disturbances to the third-stage flow F3 that may be caused by the movable wheel 12, thus optimizing the heat exchange between air and oil.

[0042] The stator corresponds to a row of stator blades arranged in the third-order flow path downstream of the splitter nose 14. Alternatively, the stator may be located upstream of the splitter nose 14 and downstream of the movable wheel 12.

[0043] The heat exchanger 18 extends radially and axially in the upstream section 20 of the tertiary flow path 16 and has a divergent longitudinal section in the flow direction of the tertiary flow F3.

[0044] In the example shown, heat exchanger 18 is axially arranged between low-pressure compressor 17 and high-pressure compressor 15.

[0045] The “VBV” (Variable Bleed Valve) type exhaust passage 19 has an outlet that passes through the inner wall of the tertiary flow path 16 and is arranged axially downstream of the heat exchanger 18. The “VBV” passage performs the exhaust function by returning a portion of the mainstream F1 toward the tertiary flow F3, which, for example, allows any ice particles to be discharged from the mainstream F1 to prevent the high-pressure compressor 15 from becoming clogged, especially if the flow rate of the mainstream F1 becomes too low.

[0046] Advantageously, the outlet of the “VBV” channel 19 is located downstream of the heat exchanger 18, protecting the heat exchanger from any risk of blockage.

[0047] The heat exchanger 18 may extend continuously for 360° around the longitudinal axis 8 of the turbine engine 2 in the upstream section 20 of the flow path 16. Preferably, the heat exchanger 18 extends discontinuously for 360° around the longitudinal axis 8 and is subdivided into multiple angular segments, each of which can perform a heat exchange function between air and oil, and the heat exchange function may differ in one segment from another.

[0048] The heat exchanger 18 is of the "ACOC" (air-cooled oil cooler) type and includes an oil passage extending into the tertiary flow path, the oil passage extending radially and axially, particularly between the upper and lower walls of the heat exchanger 18.

[0049] Advantageously, the "ACOC" heat exchanger 18 allows heat exchange between air and oil, preferably cooling the oil with air. The oil temperature can reach an operating temperature of up to 180°C and a flow rate of up to 30,000 l / h. In this respect, the exchanger 18 can be used to cool oil used in various components of an aircraft, particularly motors, gearboxes, generators, and any electronic components requiring cooling.

[0050] A single heat exchanger 18 can combine the cooling of several functional components or oil circuits of a turbine engine, depending on different parameters associated with oil cooling requirements, namely inlet temperature, flow rate, required outlet temperature, or air conditions. Different circuits can be in thermal contact or isolated. The heat exchanger 18, in particular its oil passages, can withstand low oil temperatures up to -54°C.

[0051] As described above Figure 2 and Figure 3 .

[0052] Figure 4An embodiment of the invention is shown, and a ring-shaped flow path V for airflow in a turbine engine is illustrated in a very schematic manner.

[0053] The turbine engine can be as described above and... Figure 1 The diagram shows a three-flow turbine engine. Therefore, the flow path V is understood as a third-stage flow path 16 for the third-stage flow F3.

[0054] Alternatively, the turbine engine can be a two-flow turbine engine, and the flow path V can be a secondary flow path for the secondary flow.

[0055] Therefore, it should be understood that the type of turbine engine is not limiting in the context of this invention.

[0056] In addition to the flow path V, the turbine engine according to the invention also includes a motor M and at least one device E.

[0057] The motor M is preferably a gas generator of a turbine engine and therefore includes at least one compressor, an annular combustion chamber and at least one turbine.

[0058] The at least one device E is, for example, a motor or multiple motors.

[0059] The flow path V has an annular shape around axis 8, which is typically the longitudinal axis of the turbine engine. The flow path includes two coaxial annular walls, an inner annular wall 101 and an outer annular wall 102, which are connected to each other by radial arms 100. In the example shown, there are four radial arms 100.

[0060] Arm 100 divides the flow path V into corner sectors, some of which are empty to allow airflow to pass through unobstructed, while other corner sectors are occupied by exchangers 210, 220, and 230.

[0061] According to the present invention, the turbine engine is equipped with two ACOC type exchangers 210 and 220 and one OCOC type exchanger.

[0062] The first exchanger 210 can be swept by an airflow flowing in the flow path V and includes a first oil circuit C1 connected to a cooling system S1 for cooling the motor M.

[0063] The second heat exchanger 220 can be swept by an airflow and includes a second oil circuit C2 connected to a cooling system S2 for cooling one or more devices E.

[0064] The third heat exchanger 230 is not necessarily located in the flow path because it is not configured to be swept by the airflow. The third heat exchanger 230 includes two separate loops, referred to as the third oil loop C3 and the fourth oil loop C4.

[0065] In the example shown, each exchanger 210, 220 is located in the flow path V and occupies a portion of the channel segment of the flow path V. For example, the first exchanger 210 may occupy the entire radial range or dimension of the flow path, or only a portion of the radial range, and extend circumferentially over a portion (e.g., 2 / 3) of the corner sector of the flow path V between the two arms 100. The second exchanger 220 may occupy the entire radial range or dimension of the flow path, or only a portion of the radial range, and extend circumferentially over part or all of the other corner sector of the flow path V between the two arms 100.

[0066] Each switch 210, 220, for example, has an angular range of approximately 30° to 90° around axis 8.

[0067] Preferably, the cooling capacity of the third heat exchanger 230 is lower than that of the first heat exchanger 210 and also lower than that of the second heat exchanger 220.

[0068] Figure 5 and Figure 6 The fluid connections between exchangers 210, 220, and 230 are shown, particularly the fluid connections between loops C1, C2, C3, and C4 of these exchangers.

[0069] The turbine engine according to the present invention includes connecting valves 310 and 320 for connecting a first circuit C1, a second circuit C2, and a third circuit C3. The connecting valves 310 and 320 are capable of being respectively located in… Figure 5 and Figure 6 The two different configurations shown are illustrated in the figure.

[0070] exist Figure 5 In the first configuration shown, the third loop C3 is isolated from the first loop C1, and the fourth loop C4 is isolated from the second loop C2.

[0071] exist Figure 6 In the second configuration shown, the third loop C3 is connected in series with the first loop C1, and the fourth loop C4 is connected in series with the second loop C2.

[0072] Advantageously, in the second configuration, the outlet C3s of the third circuit C3 is connected to the inlet C1e of the first circuit C1, and the outlet C4s of the fourth circuit C4 is connected to the inlet C2e of the second circuit C2. In other words, oil circulates in the third exchanger 230 before being supplied to the first exchanger 210, and oil circulates in the third exchanger 230 before being supplied to the second exchanger 220.

[0073] In the example shown, the first loop C1 includes a first inlet valve 410 connected to an inlet C1e of the first loop C1. The first loop C1 may also include a first outlet valve (not shown) connected to an outlet C1s of the first loop C1.

[0074] The second circuit C2 includes a second inlet valve 420 connected to the inlet C2e of the second circuit C2. The second circuit C2 may also include a second outlet valve connected to the outlet C2s of the second circuit C2.

[0075] Connecting valves 310 and 320 are connected upstream of the inlets C3e and C4e of the third circuit C3 and the fourth circuit C4, respectively.

[0076] The connecting valve 310 can be installed between the connection point P1 of the inlet C1e of the first circuit C1 located upstream of the first inlet valve 410 and the inlet C3e of the circuit C3. The outlet C3s of the circuit can be connected to another connection point P2 of the inlet C1e of the first circuit C1 located downstream of the first inlet valve 410.

[0077] The connecting valve 320 can be installed between the connection point P3 of the inlet C2e of the second circuit C2, located upstream of the second inlet valve 420, and the inlet C4e of the circuit C4. The outlet C4s of the circuit C4 can be connected to another connection point P4 of the inlet C2e of the second circuit C2, located downstream of the second inlet valve 420.

[0078] The present invention also relates to a cooling method for a turbine engine according to the present invention, the method comprising two steps corresponding to the two configurations described above.

[0079] According to the first step corresponding to the first configuration, the cooling system S1 for cooling the motor M is supplied with oil that only passes through the first exchanger 210 and then exits it, and the cooling system S2 for cooling one or more devices E is supplied with oil that only passes through the second exchanger 220 and then exits it. This step and this configuration are... Figure 5 As shown, consecutive arrows indicate the flow of oil in each of exchangers 210 and 220. Exchanger 230 is isolated and not used in this step / configuration.

[0080] This first step / configuration can be used by default during most phases of turbine engine operation and aircraft flight.

[0081] According to the second step corresponding to the second configuration, the cooling system S1 for cooling the motor M is supplied with oil that has passed through the third exchanger 230, then through the first exchanger 210, and exits from the first exchanger 210; and the cooling system S2 for cooling one or more devices E is supplied with oil that has passed through the third exchanger 230, then through the second exchanger 220, and exits from the second exchanger 220. This step and this configuration are... Figure 6 As shown, consecutive arrows indicate the flow of oil in each of exchangers 210, 220, and 230. The inlet C1e of the first exchanger 210 is connected to the outlet C3s of the third circuit C3 of the third exchanger 230, such that oil leaving circuit C3 is supplied to the first exchanger 210 for further cooling. The inlet C2e of the second exchanger 220 is connected to the outlet C4s of the fourth circuit C4 of the third exchanger 230, such that oil leaving circuit C4 is supplied to the second exchanger 220.

[0082] This second step / configuration can be adopted when the aircraft is on the ground and the external ambient temperature is higher than a predetermined threshold.

[0083] The first exchanger 210 can be supplied with oil at a maximum temperature of 180°C.

[0084] The second exchanger 220 can be supplied with oil at a maximum temperature of 100°C.

Claims

1. A turbine engine (2) for an aircraft, said turbine engine comprising: - Circular flow path (V) for airflow (F3). - Motor (M) - At least one device (E). - A first ACOC type heat exchanger (210), which can be swept by the airflow (F3) and includes a first oil circuit (C1) connected to a cooling system (S1) for cooling the motor. - A second ACOC type heat exchanger (220), which can be swept by the airflow (F3) and includes a second oil circuit (C2) connected to a cooling system (S2) for cooling the at least one device (E). The turbine engine is characterized in that it further includes: - A third OCOC type heat exchanger (230), the third OCOC type heat exchanger comprising a third oil circuit and a fourth oil circuit (C3, C4) capable of exchanging heat energy between them, and - Connecting valves (310, 320) that connect the first circuit (C1) to the third circuit (C3) and the second circuit (C2) to the fourth circuit (C4), the connecting valves (310, 320) being capable of two configurations: - A first configuration, wherein the third loop (C3) is isolated from the first loop (C1), and the fourth loop (C4) is isolated from the second loop (C2), and - A second configuration, wherein the third circuit (C3) is connected in series with the first circuit (C1) to supply oil to the first circuit via the third circuit, and the fourth circuit (C4) is connected in series with the second circuit (C2) to supply oil to the second circuit via the fourth circuit.

2. The turbine engine (2) according to claim 1, wherein, In the second configuration, the outlet (C3s) of the third loop (C3) is connected to the inlet (C1e) of the first loop (C1), and the outlet (C4s) of the fourth loop (C4) is connected to the inlet (C2e) of the second loop (C2).

3. The turbine engine (2) according to claim 1 or 2, wherein, The first circuit (C1) includes a first inlet valve (410) connected to the inlet (C1e) of the first circuit (C1), and the second circuit (C2) includes a second inlet valve (420) connected to the inlet (C2e) of the second circuit (C2).

4. The turbine engine (2) according to the preceding claim, wherein, The connecting valves (310, 320) include: - A first connecting valve (310) is installed between the connection point (P1) of the inlet (C1e) of the first circuit (C1) located upstream of the first inlet valve (410) and the inlet (C3e) of the third circuit (C3), and - A second connecting valve (320) is installed between the connection point (P3) of the inlet (C2e) of the second circuit (C2) located upstream of the second inlet valve (420) and the inlet (D4e) of the fourth circuit (C4).

5. The turbine engine (2) according to the preceding claim, wherein, The third circuit (C3) includes an outlet (C3s) connected to another connection point (P2) of the inlet (C1e) of the first circuit (C1) located downstream of the first inlet valve (410), and the fourth circuit (C4) includes an outlet (C4s) connected to another connection point (P4) of the inlet (C2e) of the second circuit (C2) located downstream of the second inlet valve (420).

6. The turbine engine (2) according to any one of the preceding claims, wherein, The third heat exchanger (330) is located outside the flow path (V).

7. The turbine engine (2) according to any one of the preceding claims, wherein, The flow path (V) is a secondary flow path for the flow of secondary airflow, and the turbine engine also includes a primary flow path for the flow of primary airflow within the motor (M).

8. The turbine engine (2) according to any one of claims 1 to 5, wherein, The flow path (V) is a third-order flow path for the flow of the third-order airflow (F3). The turbine engine also includes two annular flow paths for the flow of the main airflow and the secondary airflow (F1, F2), which are the main flow path and the secondary flow path, respectively.

9. The turbine engine (2) according to the preceding claim, wherein, The tertiary flow path is radially located between the primary flow path and the secondary flow path.

10. The turbine engine (2) according to any one of the preceding claims, wherein, The cooling capacity of the third heat exchanger (230) is lower than that of the first heat exchanger (210) and lower than that of the second heat exchanger (220).

11. The turbine engine (2) according to any one of the preceding claims, wherein, The at least one device (E) includes a motor.

12. A cooling method for a turbine engine (2), said turbine engine being a turbine engine according to any one of the preceding claims, wherein, The method includes two steps corresponding to the two configurations: - Corresponding to the first step of the first configuration, wherein the cooling system (C1) for cooling the motor (M) is supplied with oil exiting the first exchanger (210), and the cooling system (S2) for cooling the at least one device (E) is supplied with oil exiting the second exchanger (220), and - Corresponding to the second step of the second configuration, wherein the cooling system (S2) for cooling the motor (M) is supplied with oil that passes through the third exchanger (230) and then through the first exchanger (210), and the cooling system (S2) for cooling the at least one device (E) is supplied with oil that passes through the third exchanger (230) and then through the second exchanger (220).

13. The method according to claim 12, wherein, - The second step occurs when the aircraft is on the ground and the external ambient temperature is higher than a predetermined threshold. - The first step is the default step in all other cases.

14. The method according to claim 12 or 13, wherein, The first heat exchanger (210) is supplied with oil at a maximum temperature of 180°C, and the second heat exchanger (220) is supplied with oil at a maximum temperature of 100°C.

Images