Pre-cooling heat exchanger for aircraft and aircraft

Abstract

The present disclosure relates to the technical field of aircraft, and particularly provides a pre-cooling heat exchanger for aircraft and an aircraft. The pre-cooling heat exchanger for aircraft comprises at least three partitions, among every three adjacent partitions, two adjacent partitions form an air flow channel, and the other two adjacent partitions form a heat exchange working medium flow channel; at least one air flow channel is provided with a heat exchange fin array group and a plurality of dot array heat exchange fins, the heat exchange fin array group comprises a first fin array, and the first fin array comprises a plurality of first shape memory fins arranged in an array; the first shape memory fins are attached to one of the partitions and can deform when the air temperature reaches a first preset temperature threshold and bend towards the other partition. The plurality of dot array heat exchange fins are supported between the adjacent two partitions; the projection of the heat exchange fin array group and the dot array heat exchange fins on the partition does not overlap, thereby improving the impact resistance and heat exchange capacity of the pre-cooling heat exchanger.

Description

Technical Field

[0001] This disclosure relates to the field of aircraft technology, and in particular to a precooling heat exchanger for aircraft and an aircraft. Background Technology

[0002] The high speed of aircraft has extremely important military and civilian value, but the aerodynamic heating effect generated by aircraft during high-speed flight limits the flight limits of aircraft.

[0003] Turbine engines are a crucial component of aircraft, providing propulsion for flight. To increase the flight speed of turbine engines, related technologies utilize pre-cooling heat exchangers to cool the ramjet intake air, lowering its temperature to partially offset the temperature rise caused by aerodynamic heating during high-speed flight. However, these pre-cooling heat exchangers have poor impact resistance and their heat exchange capacity is insufficient. Summary of the Invention

[0004] In order to solve the above-mentioned technical problems, or at least partially solve the above-mentioned technical problems, this disclosure provides a precooling heat exchanger for aircraft and an aircraft, so as to improve the impact resistance and heat exchange capacity of the precooling heat exchanger.

[0005] In a first aspect, this disclosure provides a precooling heat exchanger for an aircraft, comprising at least three stacked and spaced-apart partitions. In every three adjacent partitions, an airflow channel is formed between two adjacent partitions, and a heat exchange medium flow channel is formed between another two adjacent partitions. The airflow channel is arranged along a first direction of the partitions, and the heat exchange medium flow channel is arranged along a second direction of the partitions; the first direction and the second direction are perpendicular to each other.

[0006] At least one of the airflow channels is provided with a heat exchange fin array group and a plurality of matrix heat exchange fins. The heat exchange fin array group includes a first fin array, which includes a plurality of first shape memory fins arranged in an array. In two adjacent partitions, the first shape memory fins are attached to one of the partitions when the air temperature entering the airflow channel is lower than a first preset temperature threshold, and can be deformed when the air temperature entering the airflow channel reaches the first preset temperature threshold, so that the two ends of the first shape memory fins bend toward the other partition.

[0007] Multiple lattice heat exchange fins are arranged at intervals in the airflow channel and supported between two adjacent partitions; the projections of the heat exchange fin array group and the lattice heat exchange fins on the partitions do not overlap.

[0008] Optionally, when the air temperature entering the airflow channel reaches the first preset temperature threshold, the two ends of the first shape memory fin come into contact with and adhere to another of the partitions.

[0009] Optionally, the first shape memory fin is a nickel-titanium-copper shape memory alloy fin.

[0010] Optionally, the heat exchange fin array group further includes a second fin array;

[0011] The second fin array includes a plurality of second shape memory fins arranged in an array; in two adjacent partitions, the second shape memory fins are attached to one of the partitions when the air temperature entering the airflow channel is lower than a second preset temperature threshold, and can deform when the air temperature entering the airflow channel reaches the second preset temperature threshold, so that the two ends of the second shape memory fins bend toward one of the partitions; the second preset temperature threshold is greater than the first preset temperature threshold;

[0012] The projections of the first shape memory fin, the second shape memory fin, and the lattice heat exchange fin on the partition plate do not overlap.

[0013] Optionally, along the first direction, the first shape memory fin and the second shape memory fin are arranged alternately.

[0014] Optionally, when the air temperature entering the airflow channel reaches the second preset temperature threshold, the two ends of the second shape memory fin contact and adhere to one of the partitions.

[0015] Optionally, the second shape memory fin is a nickel-titanium-iron shape memory alloy fin.

[0016] Optionally, the matrix heat exchange fins include a plurality of heat exchange support rods arranged radially;

[0017] The ends of the plurality of heat exchange support rods that are close to each other are connected to a central confluence point, and the ends of the plurality of heat exchange support rods that are away from the central confluence point respectively contact the corresponding partition plates to support the rods between two adjacent partition plates.

[0018] Optionally, among all the heat exchange support rods, at least two adjacent heat exchange support rods are further connected by a reinforcing rod between their ends away from the central confluence point, and the reinforcing rod is arranged parallel to the partition and fits against the partition;

[0019] And / or, the diameter of the heat exchange support rod is in the range of 0.3mm to 0.5mm.

[0020] Secondly, this disclosure provides an aircraft including a precooling heat exchanger for an aircraft as described above.

[0021] The precooling heat exchanger and aircraft disclosed herein include at least three stacked and spaced partitions in the precooling heat exchanger, such that in every three adjacent partitions, an air flow channel is formed between two adjacent partitions and a heat exchange medium flow channel is formed between the other two adjacent partitions, and the air flow channel and the heat exchange medium flow channel are perpendicular to each other. By arranging the two heat exchange channels perpendicularly, the heat exchange efficiency between the air and the heat exchange medium is improved.

[0022] By arranging a heat exchange fin array group and multiple matrix heat exchange fins within at least one airflow channel, the heat exchange fin array group includes a first fin array, which comprises multiple first shape memory fins arranged in an array. In two adjacent partitions, the first shape memory fins are fitted onto one of the partitions when the air temperature entering the airflow channel is below a first preset temperature threshold, and can deform when the air temperature entering the airflow channel reaches the first preset temperature threshold, causing the two ends of the first shape memory fins to bend towards the other partition. Simultaneously, multiple matrix heat exchange fins are spaced apart within the airflow channel and supported between adjacent partitions, ensuring that the projections of the heat exchange fin array group and the matrix heat exchange fins on the partitions do not overlap.

[0023] When the precooling heat exchanger starts working, a large amount of high-speed gas rushes into the precooling heat exchanger instantly. Throughout the flight, the array of heat exchange fins installed in the airflow channel provides stable support for the airflow channel, improving the overall structural strength of the precooling heat exchanger and ensuring the geometry and overall stability of the airflow channel. This effectively resists the impact of high-speed airflow on the internal structure of the precooling heat exchanger, improving its impact resistance. Furthermore, the array of heat exchange fins can also increase the contact area between the air and the precooling heat exchanger to a certain extent, thereby improving the heat exchange efficiency.

[0024] Moreover, this configuration ensures that during low-speed flight, the first shape memory fins remain straight and adhere to the baffle, guaranteeing a certain heat exchange effect while minimizing airflow obstruction. This results in low pressure loss and reduced engine energy consumption. During high-speed flight, when the air temperature reaches the first preset temperature threshold, the ends of the first shape memory fins bend, further increasing the contact area between the air and the precooling heat exchanger. This further enhances the heat exchange capacity, meeting the engine's demand for cool air. This allows the performance of the precooling heat exchanger to be well-matched with the aircraft's flight conditions, improving the precooling heat exchanger's adaptive wide-speed-range operating condition adjustment capability and providing strong support for the engine's efficient operation.

[0025] It should be understood that both the foregoing general description and the following detailed description are exemplary and intended to provide further illustration of the claimed technology. Attached Figure Description

[0026] The above and other objects, features, and advantages of this disclosure will become more apparent from the more detailed description of the embodiments thereof in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this disclosure and form part of the specification. They are used together with the embodiments of this disclosure to explain the disclosure and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0027] Figure 1 This is a schematic diagram of the structure of a precooling heat exchanger for an aircraft provided in an embodiment of the present disclosure;

[0028] Figure 2 A schematic diagram of the partition and first fin array of an aircraft precooling heat exchanger provided in an embodiment of this disclosure;

[0029] Figure 3 A schematic diagram of the structure of an aircraft precooling heat exchanger provided in an embodiment of the present disclosure when both the first shape memory fin and the second shape memory fin are deformed in the airflow channel.

[0030] Figure 4 This is a top view of the airflow channel of an aircraft precooling heat exchanger provided in an embodiment of the present disclosure.

[0031] Figure 5 This is a schematic diagram of the structure of the lattice heat exchange fins of a precooling heat exchanger for an aircraft provided in one embodiment of the present disclosure.

[0032] Among them, 1. partition; 11. air flow channel; 12. heat exchange working fluid flow channel; 2. seal; 3. first fin array; 31. first shape memory fin; 4. second fin array; 41. second shape memory fin; 5. lattice heat exchange fin; 51. heat exchange support rod; 52. central confluence point; 53. reinforcing rod. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this disclosure more apparent, exemplary embodiments according to this disclosure will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments of this disclosure. It should be understood that this disclosure is not limited to the exemplary embodiments described herein.

[0034] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below. It should be noted that the concepts of "first", "second", etc., used in this disclosure are only used to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies.

[0035] It should be noted that the terms "a" and "a plurality of" used in this disclosure are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0036] Reference Figures 1 to 5 As shown, this disclosure provides a precooling heat exchanger for aircraft, including at least three stacked and spaced-apart partitions 1.

[0037] In every three adjacent partitions 1, an air flow channel 11 is formed between two adjacent partitions 1, and a heat exchange medium flow channel 12 is formed between the other two adjacent partitions 1. The air flow channel 11 is arranged along a first direction of the partition 1, and the heat exchange medium flow channel 12 is arranged along a second direction of the partition 1. The first direction and the second direction are perpendicular to each other.

[0038] The first direction can be, for example, the width direction of partition 1, such as... Figure 1 and Figure 2 The direction indicated by XX in the diagram, the second direction could be, for example, the length direction of partition 1, for example... Figure 1 and Figure 2 The YY direction is shown in the diagram.

[0039] The partition 1 is made of a material that meets the requirements of high temperature resistance, corrosion resistance, and good thermal conductivity in aerospace applications, such as high-temperature alloys, high-temperature stainless steel, or titanium alloys. For example, the thickness of the partition 1 can be set to 0.5 mm.

[0040] In specific implementation, along the first direction, seals 2 are provided on both sides of the corresponding airflow channels 11 of two adjacent partitions 1, and the two adjacent partitions 1 and the corresponding seals 2 together define a sealed flow channel for airflow. Along the second direction, seals 2 are provided on both sides of the corresponding heat exchange medium flow channels 12 of two adjacent partitions 1, and the two adjacent partitions 1 and the corresponding seals 2 together define a sealed flow channel for heat exchange medium flow.

[0041] In a specific implementation, the heat exchange medium flow channel 12 has an inlet and an outlet. For example, the inlet of the heat exchange medium flow channel 12 can be connected to the heat exchange medium storage container, and the heat exchange medium is supplied to the heat exchange medium flow channel 12 through the heat exchange medium storage container, so as to realize the circulation of the heat exchange medium in the heat exchange medium flow channel 12.

[0042] For example, the heat exchange medium can be a high-boiling-point liquid metal, such as a gallium-indium alloy, or Ga... 62 In 22 Sn 16 Melting point -19℃, boiling point 2000℃, thermal conductivity 26W / m·K.

[0043] Of course, the heat exchange medium can also be sodium-potassium alloy, lead-bismuth alloy, etc. In addition, the heat exchange medium can also be a gaseous heat exchange medium.

[0044] For example, the heat exchange medium channel 12 may adopt a microchannel design, with an equivalent diameter of, for example, 0.8 mm and a flow rate of, for example, 5 m / s.

[0045] Specifically, the heat of the air entering the airflow channel 11 is transferred to the baffle 1, and then from the baffle 1 to the heat exchange medium in the adjacent heat exchange medium flow channel 12. After absorbing the heat of the air, the heat exchange medium flows out from the outlet of the heat exchange medium flow channel 12, thereby cooling the air. The cooled air in the airflow channel 11 eventually flows from the outlet end of the airflow channel 11 to the engine, and enters the engine from the engine's air intake, thereby cooling the engine's intake air temperature, ensuring the engine's performance, and thus ensuring that it can fly at higher speeds.

[0046] At least one airflow channel 11 is provided with a heat exchange fin array group and a plurality of matrix heat exchange fins 5. The heat exchange fin array group includes a first fin array 3, which includes a plurality of first shape memory fins 31 arranged in an array. In two adjacent partitions 1, the first shape memory fins 31 are attached to one of the partitions 1 when the air temperature entering the airflow channel 11 is lower than a first preset temperature threshold, and can deform when the air temperature entering the airflow channel 11 reaches the first preset temperature threshold, so that the two ends of the first shape memory fins 31 bend toward the other partition 1.

[0047] Understandably, the higher the flight speed, the higher the temperature of the air entering through the airflow channel 11.

[0048] In other words, the first shape memory fin 31 in the first fin array 3 can switch between a contracted state that is in contact with the partition 1 and an expanded state that is bent and deformed toward the opposing partition 1 according to temperature changes, thus presenting two forms: a contracted state and an expanded state.

[0049] When the aircraft is flying at low speed, the first shape memory fins 31 are straight and attached to the partition 1, thus ensuring a certain heat exchange effect during low-speed flight while the first fin array 3 does not excessively obstruct the airflow. That is, during low-speed flight, the pressure loss is small, reducing the energy consumption of the engine. When the aircraft is flying at high speed, that is, when the air temperature reaches the first preset temperature threshold, the two ends of the first shape memory fins 31 bend, thereby further increasing the contact area between the air and the pre-cooling heat exchanger, and thus further improving the heat exchange efficiency.

[0050] Moreover, the first shape memory fin 31 deforms and bends towards the opposite partition 1, which can also support the partition 1 to a certain extent and prevent the partition 1 from deforming too much and being damaged or broken.

[0051] Multiple lattice heat exchange fins 5 are arranged at intervals in the air flow channel 11 and supported between two adjacent partitions 1; the projections of the heat exchange fin array group and the lattice heat exchange fins 5 on the partition 1 do not overlap.

[0052] Since the lattice heat exchange fins 5 are supported between two adjacent partitions 1, when the precooling heat exchanger starts working, a large amount of high-speed gas rushes into the precooling heat exchanger instantly and throughout the entire flight process, the lattice heat exchange fins 5 provide stable support for the airflow channel 11, improve the overall structural strength of the precooling heat exchanger, ensure the geometry and overall stability of the airflow channel 11, thereby effectively resisting the impact of high-speed airflow on the internal structure of the precooling heat exchanger, improving the impact resistance of the precooling heat exchanger, and the lattice heat exchange fins 5 can also increase the contact area between the air and the precooling heat exchanger to a certain extent, thereby improving the heat exchange efficiency.

[0053] For example, the lattice heat exchange fins 5 can be formed into a three-dimensional lattice structure from nickel-based superalloys through additive manufacturing, possessing high rigidity (compressive strength > 300 MPa), low flow resistance (pressure loss is 30% of that of traditional fins), and impact resistance. Its low flow resistance ensures a certain heat exchange effect without excessively hindering airflow, and it consistently provides solid support for the entire airflow channel 11, guaranteeing the stable operation of the precooling heat exchanger under harsh conditions.

[0054] The precooling heat exchanger for aircraft provided in this embodiment includes at least three stacked and spaced partitions 1, such that in every three adjacent partitions 1, an air flow channel 11 is formed between two adjacent partitions 1, and a heat exchange medium flow channel 12 is formed between the other two adjacent partitions 1, and the air flow channel 11 and the heat exchange medium flow channel 12 are perpendicular. By arranging the two heat exchange channels perpendicularly, the heat exchange efficiency between air and heat exchange medium is improved.

[0055] By arranging a heat exchange fin array group and multiple matrix heat exchange fins 5 within at least one airflow channel 11, the heat exchange fin array group includes a first fin array 3, which includes multiple first shape memory fins 31 arranged in an array. In two adjacent partitions 1, the first shape memory fins 31 are fitted onto one of the partitions 1 when the air temperature entering the airflow channel is below a first preset temperature threshold, and can deform when the air temperature entering the airflow channel 11 reaches the first preset temperature threshold, so that both ends of the first shape memory fins 31 bend towards the other partition 1. Simultaneously, multiple matrix heat exchange fins 5 are spaced apart within the airflow channel 11 and supported between two adjacent partitions 1, ensuring that the projections of the heat exchange fin array group and the matrix heat exchange fins 5 on the partitions 1 do not overlap.

[0056] When the precooling heat exchanger starts working, a large amount of high-speed gas rushes into the precooling heat exchanger instantly. Throughout the flight, because the airflow channel 11 is equipped with array heat exchange fins 5, the array heat exchange fins 5 provide stable support for the airflow channel 11, improving the overall structural strength of the precooling heat exchanger and ensuring the geometry and overall stability of the airflow channel 11. This effectively resists the impact of high-speed airflow on the internal structure of the precooling heat exchanger, improving the impact resistance of the precooling heat exchanger. In addition, the array heat exchange fins 5 can also increase the contact area between the air and the precooling heat exchanger to a certain extent, thereby improving the heat exchange efficiency.

[0057] Moreover, this configuration ensures that during low-speed flight, the first shape memory fins 31 remain straight and adhere to the partition 1, thus guaranteeing a certain heat exchange effect while minimizing airflow obstruction. This results in low pressure loss and reduced engine energy consumption. During high-speed flight, when the air temperature reaches the first preset temperature threshold, the ends of the first shape memory fins 31 bend, further increasing the contact area between the air and the precooling heat exchanger. This further enhances the heat exchange capacity, meeting the engine's demand for cold air. This allows the performance of the precooling heat exchanger to be well-matched with the aircraft's flight conditions, improving the precooling heat exchanger's adaptive wide-speed-range operating condition adjustment capability and providing strong support for the engine's efficient operation.

[0058] In some embodiments, when the air temperature entering the airflow channel 11 reaches a first preset temperature threshold, the two ends of the first shape memory fin 31 come into contact with and adhere to another partition 1.

[0059] In other words, during high-speed flight (when the air temperature rises), the first shape memory fin 31 bends and deforms towards the opposite partition 1, and the two ends of the first shape memory fin 31 come into contact with and adhere to the partition 1. This allows the heat transferred from the air to the first shape memory fin 31 to be quickly transferred to the partition 1, and then to the heat exchange medium in the heat exchange medium flow channel 12, thereby improving the heat exchange efficiency and heat exchange capacity. Moreover, this also allows the first shape memory fin 31 to play a supporting role for the air flow channel 11 to a certain extent, further improving the impact resistance of the precooling heat exchanger and extending its service life.

[0060] Specifically, the first shape memory fin 31 can be a shape memory alloy (SMA) fin.

[0061] In some embodiments, the first shape memory fin 31 is a nickel-titanium-copper shape memory alloy (Ni-Ti-Cu alloy) fin.

[0062] For example, the phase transformation temperature T1 of the Ni-Ti-Cu alloy fin is 150℃±10℃. In the low-speed state, it shrinks and adheres to the partition 1 (the thickness of the first shape memory fin 31 is, for example, 0.1mm~0.2mm). In the high-speed state, it unfolds into a flat and discontinuous fin (the height of the first shape memory fin 31 is, for example, 3mm~5mm, and the distance between the two ends of the first shape memory fin 31 can be twice its height, for example, 6mm~10mm).

[0063] This configuration further ensures the sensitivity of the first shape memory fin 31 to deformation with temperature changes, improves the response speed, and thus improves the heat exchange capacity, thereby enhancing the performance of the precooling heat exchanger and its high degree of matching with the flight status of the aircraft.

[0064] Of course, in other embodiments, the first shape memory fin 31 may also be an iron-based shape memory alloy, etc.

[0065] In some embodiments, the heat exchange fin array group further includes a second fin array 4. The second fin array 4 includes a plurality of second shape memory fins 41 arranged in an array.

[0066] Specifically, in two adjacent partitions 1, the second shape memory fin 41 is attached to one of the partitions 1 when the air temperature entering the airflow channel 11 is lower than the second preset temperature threshold, and can deform when the air temperature entering the airflow channel 11 reaches the second preset temperature threshold, so that the two ends of the second shape memory fin 41 bend toward one of the partitions 1. The second preset temperature threshold is greater than the first preset temperature threshold.

[0067] The projections of the first shape memory fin 31, the second shape memory fin 41, and the lattice heat exchange fin 5 onto the partition plate 1 do not overlap.

[0068] In other words, the second shape memory fin 41 in the second fin array 4 can switch between a contracted state that is in contact with the partition 1 and an expanded state that is bent and deformed toward the opposing partition 1 according to temperature changes, thus presenting two forms: a contracted state and an expanded state.

[0069] The above configuration implements a segmented deployment mechanism and gradient deformation of the heat exchange fin array, enabling the precooling heat exchanger to automatically adjust the working shape of the fins according to the air temperature and flow velocity at different flight Mach numbers. This achieves optimal heat exchange performance under various operating conditions, improving the precooling heat exchanger's adaptive wide-speed-range operating capability. At low speeds, pressure loss is low, reducing engine energy consumption. At high speeds, the heat exchange capacity is strong, fully meeting the engine's demand for cold air. This solves the problem of thermal-fluid coupling mismatch in traditional heat exchangers, ensuring a high degree of matching between the precooling heat exchanger's performance and the aircraft's flight conditions, providing strong support for the engine's efficient operation.

[0070] For example, in mode one (flight Mach number Ma less than 2.5), the first shape memory fin 31 and the second shape memory fin 41 are tightly attached to the surface of the corresponding baffle 1. At this time, the cross-section of the airflow channel 11 is mainly composed of the lattice heat exchange fins 5 and the baffle 1, allowing the airflow to flow smoothly with low resistance, which is suitable for the low-speed flight phase from takeoff to Ma 2.5. This structural design ensures that when high-speed gas enters the heat exchanger, the impact force is mainly borne by the lattice heat exchange fins 5, effectively protecting the internal structure of the heat exchanger and avoiding damage caused by airflow impact, while ensuring normal airflow and a certain heat exchange effect.

[0071] In Mode 2 (flight Mach number Ma between 2.5 and 3), as the flight speed increases, the air temperature rises to a first preset temperature threshold. The first shape memory fins 31 of the first fin array 3 undergo a shape memory effect upon heating, forming straight, discontinuous fins. These heat-deformed fins cooperate with the lattice heat exchange fins 5. At this time, the cross-section of the airflow channel 11 changes, increasing the heat exchange area. During the airflow process, it comes into full contact with the deformed first shape memory fins 31 and the lattice heat exchange fins 5, allowing heat in the air to be transferred to the heat exchange medium more effectively, improving heat exchange efficiency and achieving a better pre-cooling effect, meeting the aircraft's requirements for pre-cooler heat exchange capacity at this stage. In this mode, the lattice heat exchange fins 5 still play a supporting and impact-resistant role, ensuring the stability and reliability of the pre-cooling heat exchanger structure under changes in airflow speed and temperature.

[0072] In Mode 3 (flight Mach number Ma exceeds 3), the aircraft enters the high-altitude, high-speed flight phase, where the air temperature rises further, reaching the second preset temperature threshold. At this time, the second shape memory fins 41 of the second fin array 4 also exhibit a shape memory effect after being heated, greatly enhancing the degree of airflow disturbance. This allows for more thorough heat exchange between the air and the fins, significantly enhancing the heat transfer capacity. Consequently, this ensures that the engine receives sufficiently cool air during hypersonic flight, maintaining its efficient and stable operation.

[0073] Throughout the flight, the lattice heat exchange fins 5 play a crucial supporting and shock-resistant role, ensuring the stability and reliability of the internal structure of the precooling heat exchanger under different operating conditions. This effectively solves the problems of insufficient shock resistance and thermal-fluid coupling mismatch in traditional precoolers, providing an efficient and reliable solution for engine intake precooling of hypersonic vehicles.

[0074] Reference Figures 1 to 4 As shown, in some embodiments, the first shape memory fin 31 and the second shape memory fin 41 are arranged alternately along the first direction.

[0075] This configuration ensures that during high-speed flight, both the second shape memory fin 41 and the first shape memory fin 31 undergo bending deformation, and they are arranged in an alternating pattern, forming a serrated fin structure. This alternating serrated fin greatly enhances the turbulence between the air and the fins, making the heat exchange between the air and the fins more complete and significantly enhancing the heat exchange capacity. This meets the high heat exchange capacity requirements of the precooler during high-speed flight and maintains its efficient and stable operation.

[0076] In some embodiments, when the temperature of the air entering the airflow channel 11 reaches a second preset temperature threshold, the two ends of the second shape memory fin 41 come into contact with and adhere to one of the partitions 1.

[0077] During high-speed flight (when the air temperature rises), the second shape memory fin 41 bends and deforms towards the opposite partition 1, and the two ends of the second shape memory fin 41 come into contact with and adhere to the partition 1. This allows the heat transferred from the air to the second shape memory fin 41 to be quickly transferred to the partition 1, and then to the heat exchange medium in the heat exchange medium flow channel 12, thereby improving the heat exchange efficiency. Moreover, this also allows the second shape memory fin 41 to support the air flow channel 11 to a certain extent, further improving the impact resistance of the precooling heat exchanger and extending its service life.

[0078] Specifically, the second shape memory fin 41 can be a shape memory alloy (SMA) fin.

[0079] In some embodiments, the second shape memory fin 41 is a nickel-titanium-iron shape memory alloy (Ni-Ti-Fe alloy) fin.

[0080] For example, the phase transformation temperature T2 of the Ni-Ti-Fe alloy fins is 250℃±10℃. In the low-speed state, it shrinks and adheres to the opposite partition 1 (the thickness of the second shape memory fin 41 is, for example, 0.1mm~0.2mm, specifically, 0.15mm). In the high-speed state, it unfolds and forms a serrated fin with the first shape memory fin 31 (the height of the second shape memory fin 41 is, for example, 3mm~5mm, and the distance between the two ends of the second shape memory fin 41 can be twice its height, for example, 6mm~10mm), thus strengthening the heat exchange channel.

[0081] This configuration further ensures the sensitivity of the second shape memory fin 41 to deformation with temperature changes, improves the response speed, and thus improves the performance of the precooling heat exchanger and its high degree of matching with the flight state of the aircraft.

[0082] Of course, in other embodiments, the second shape memory fin 41 may also be a copper-based shape memory alloy, etc.

[0083] In specific implementation, for example, when the air temperature reaches a first preset temperature threshold, the bending angle at both ends of the first shape memory fin 31 is 90°. Similarly, when the air temperature reaches a second preset temperature threshold, the bending angle at both ends of the second shape memory fin 41 is 90°. The response time of the first shape memory fin 31 and the second shape memory fin 41 to air temperature is, for example, no greater than 0.3 seconds.

[0084] Reference Figure 5 As shown, in some embodiments, the lattice heat exchange fins 5 include a plurality of heat exchange support rods 51 arranged radially.

[0085] Among them, the ends of the multiple heat exchange support rods 51 that are close to each other are connected to the central confluence point 52, and the ends of the multiple heat exchange support rods 51 that are away from the central confluence point 52 respectively contact the corresponding partition 1 to support between two adjacent partitions 1.

[0086] This configuration allows the lattice heat exchange fins 5 to form a spatial grid structure. This structure endows the fins with extremely high rigidity, enabling them to remain stable under the impact of high-speed airflow and preventing deformation and structural failure. This provides superior stability support for the airflow channel 11, thereby extending the service life of the pre-cooling heat exchanger and improving its reliability and stability in complex flight environments. Simultaneously, this structure also results in lower pressure loss in the airflow channel 11, reducing engine energy consumption.

[0087] For example, the unit cell size of the lattice heat exchange fin 5 is no greater than 3mm×3mm×3mm, and the diameter of the heat exchange support rod 51 is, for example, 0.3mm to 0.5mm. Specifically, it can be formed between two adjacent partition plates 1 by selective laser melting (SLM).

[0088] Furthermore, in some embodiments, among all heat exchange support rods 51, at least two adjacent heat exchange support rods 51 are connected by a reinforcing rod 53 at one end away from the central meeting point 52. The reinforcing rod 53 is arranged parallel to the partition 1 and is attached to the partition 1.

[0089] This configuration further enhances the structural strength of the lattice heat exchange fins 5, thereby improving the support effect of the lattice heat exchange fins 5 on the airflow channel 11. At the same time, it allows the heat in the air to be quickly transferred to the partition 1 via the heat exchange support rod 51 and the reinforcing rod 53, and then to the heat exchange medium on the other side of the partition 1, further improving the heat exchange efficiency.

[0090] The precooling heat exchanger for aircraft provided in this disclosure achieves a balance between shock resistance and wide-velocity adaptive capability through the rigid support of the lattice heat exchange fins 5 and the coordinated design of the first fin array 3 and the second fin array 4. This solves the problems of insufficient shock resistance and thermal-fluid coupling mismatch in traditional heat exchangers.

[0091] This disclosure also provides an aircraft, including an engine and a precooling heat exchanger. The precooling heat exchanger is located on the engine's intake side and is used to cool the intake air, reducing the engine's inlet air temperature and offsetting the increase in intake air temperature caused by aerodynamic heating during high-speed flight, thus enabling the engine to fly at higher speeds.

[0092] The specific structure and implementation principle of the precooling heat exchanger in this embodiment are the same as those of the precooling heat exchanger for aircraft provided in the above embodiments, and can bring the same or similar technical effects. They will not be described in detail here, but can be referred to the description of the above embodiments.

[0093] The precooling heat exchanger provided in this disclosure can also be applied to extreme thermo-mechanical coupling environments such as reusable vehicles.

[0094] The above description is merely an embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features disclosed in this disclosure that have similar functions.

[0095] While specific embodiments of this disclosure have been described in detail by way of example, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.

Claims

1. A precooling heat exchanger for aircraft, characterized in that, It includes at least three stacked and spaced partitions. In every three adjacent partitions, an air flow channel is formed between two adjacent partitions, and a heat exchange medium flow channel is formed between another two adjacent partitions. The air flow channel is arranged along a first direction of the partitions, and the heat exchange medium flow channel is arranged along a second direction of the partitions. The first direction and the second direction are perpendicular to each other. At least one of the airflow channels is provided with a heat exchange fin array group and a plurality of matrix heat exchange fins. The heat exchange fin array group includes a first fin array, which includes a plurality of first shape memory fins arranged in an array. In two adjacent partitions, the first shape memory fins are attached to one of the partitions when the air temperature entering the airflow channel is lower than a first preset temperature threshold, and can be deformed when the air temperature entering the airflow channel reaches the first preset temperature threshold, so that the two ends of the first shape memory fins bend toward the other partition. Multiple lattice heat exchange fins are arranged at intervals in the airflow channel and supported between two adjacent partitions; the projections of the heat exchange fin array group and the lattice heat exchange fins on the partitions do not overlap. When the temperature of the air entering the airflow channel reaches the first preset temperature threshold, the two ends of the first shape memory fin come into contact with and adhere to another of the partitions. The heat exchange fin array group further includes a second fin array; the second fin array includes a plurality of second shape memory fins arranged in an array; in two adjacent partitions, the second shape memory fins are attached to one of the partitions when the air temperature entering the air channel is lower than a second preset temperature threshold, and can deform when the air temperature entering the air channel reaches the second preset temperature threshold, so that the two ends of the second shape memory fins bend toward one of the partitions; the second preset temperature threshold is greater than the first preset temperature threshold; the projections of the first shape memory fins, the second shape memory fins and the matrix heat exchange fins on the partitions do not overlap; When the temperature of the air entering the airflow channel reaches the second preset temperature threshold, the two ends of the second shape memory fin come into contact with and adhere to one of the partitions.

2. The precooling heat exchanger for aircraft according to claim 1, characterized in that, The first shape memory fin is a nickel-titanium-copper shape memory alloy fin.

3. The precooling heat exchanger for aircraft according to claim 1, characterized in that, Along the first direction, the first shape memory fin and the second shape memory fin are arranged alternately.

4. The precooling heat exchanger for aircraft according to claim 1, characterized in that, The second shape memory fin is a nickel-titanium-iron shape memory alloy fin.

5. The precooling heat exchanger for aircraft according to claim 1 or 2, characterized in that, The lattice heat exchange fins include multiple heat exchange support rods arranged radially; The ends of the plurality of heat exchange support rods that are close to each other are connected to a central confluence point, and the ends of the plurality of heat exchange support rods that are away from the central confluence point respectively contact the corresponding partition plates to support the rods between two adjacent partition plates.

6. The precooling heat exchanger for aircraft according to claim 5, characterized in that, Of all the heat exchange support rods, at least two adjacent heat exchange support rods are connected by a reinforcing rod between their ends away from the central confluence point. The reinforcing rod is arranged parallel to the partition and is in contact with the partition. And / or, the diameter of the heat exchange support rod is in the range of 0.3mm to 0.5mm.

7. An aircraft, characterized in that, Includes the precooling heat exchanger for aircraft as described in any one of claims 1 to 6.

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