Fuel oil and lubricating oil micro-channel heat exchanger with high power-to-weight ratio

Abstract

The invention discloses a high-power-to-weight-ratio fuel oil and lubricating oil micro-channel heat exchanger which comprises two upper cover plate connectors, an upper cover plate, an upper solid plate, a heat exchange plate set, a lower solid plate, a lower cover plate and two lower cover plate connectors, and the heat exchange plate set comprises hot side heat exchange plates and cold side heat exchange plates which are sequentially and alternately arranged. The sine wave-shaped groove parts of the hot side heat exchange plate and the cold side heat exchange plate form a heat exchange channel of hot fluid and a heat exchange channel of cold fluid, the cold fluid and the hot fluid exchange heat in the main heat exchange section in the middle of the heat exchanger in a reverse flow mode, and the inlet section and the outlet section of the end head part of the heat exchanger are designed in a 90-degree cross flow and complete overlapping mode. The invalid heat exchange area is reduced, and the heat exchange efficiency of the heat exchanger end is improved. The heat exchanger is made of AlSi10Mg aluminum alloy and is assembled in a mode of combining 3D printing and friction stir welding. According to the fuel oil and lubricating oil micro-channel heat exchanger, the high power-to-weight ratio and low resistance can be achieved at the same time, and the high pressure bearing capacity is achieved.

Description

Technical Field

[0001] The invention relates to a fuel oil and lubricating oil microchannel heat exchanger with a high power-to-weight ratio. Background Art

[0002] In high-speed aircraft engines, bearings and gears require continuous and efficient lubrication of lubricating oil, and the rotation and transmission process will generate a lot of heat. Coupled with the heat conduction of the engine body, the lubricating oil temperature will rise significantly. If the temperature is too high, the viscosity and acid value will increase, and even coking will occur, threatening the safe operation of the engine. The fuel oil heat exchanger uses the engine fuel - fuel as a cold source to effectively cool the engine lubricating oil, dissipate the heat load of the lubrication process, and ensure that the lubricating oil in the flight envelope always works within a safe temperature range.

[0003] At present, traditional aviation fuel oil heat exchangers mostly use shell and tube heat exchangers. To improve the heat transfer performance of shell and tube heat exchangers, it is usually achieved by increasing the number of channels or lengthening the channel length. However, this measure will also increase the flow resistance and weight of the shell and tube heat exchanger, and the increased flow resistance is much higher than the improved heat transfer performance. Patent CN110043342 A discloses a high-pressure fuel oil radiator for aircraft engines, which adopts a dual-core, multi-flow shell and tube heat exchange structure, with a heat transfer capacity of 72.6kW, a weight of 16.9kg, and a power-to-weight ratio of only 4.3kW / kg. In the special application of aircraft engines, flow resistance and weight are indicators that are equally important as heat transfer. Simply or preferentially increasing heat transfer can easily cause excessive weight, and for high-viscosity fluids such as fuel and lubricating oil, the resistance will increase significantly. Therefore, to achieve an ultra-high power-to-weight ratio (such as more than 15kW / kg) and a low resistance index, the traditional fuel oil heat exchanger cannot meet the requirements.

[0004] To achieve an ultra-high power-to-weight ratio, a compact enhanced heat exchange structure must be adopted, and all heat exchange areas must be utilized as much as possible. Chinese patent application CN 114993078 A discloses a microchannel heat exchanger suitable for high-viscosity oil working fluids. The heat exchanger uses S30408 ​​austenitic stainless steel or titanium alloy, and the heat exchange core uses a zigzag microchannel. This structure can effectively improve the heat exchange performance. However, some areas of the inlet section and the outlet section are invalid heat exchange areas. This part of the invalid heat exchange area will increase the weight of the fuel oil heat exchanger, but it is not beneficial to heat exchange, thereby reducing the power-to-weight ratio. In addition, the inlet section and the outlet section do not use the same zigzag channel as the core, but a straight channel, and the cold and hot sides form a 60° cross-flow heat exchange form, so the heat exchange performance at this point is relatively low. In addition, the flow resistance of the core zigzag channel will be relatively large. More importantly, the density of S30408 ​​austenitic stainless steel and titanium alloy is relatively large. These factors are not conducive to improving the power-to-weight ratio of the fuel oil heat exchanger.

[0005] Therefore, the existing heat exchanger structure suitable for fuel and lubricating oil with high power-to-weight ratio, low resistance, high temperature and high pressure resistance needs to be improved and developed. Summary of the invention

[0006] Purpose of the invention: It is difficult to achieve a greater breakthrough in the power-to-weight ratio of the traditional design of aviation fuel and lubricating oil heat exchangers. The purpose of the present invention is to provide a fuel and lubricating oil heat exchanger with a high power-to-weight ratio, which adopts corrugated microchannels to significantly improve the heat exchange performance of the heat exchanger without significantly increasing the weight and resistance of the heat exchanger, thereby achieving a high power-to-weight ratio and low resistance of the heat exchanger.

[0007] Technical solution: The purpose of the present invention is achieved through the following technical solution. The high power-to-weight ratio fuel oil microchannel heat exchanger of the present invention comprises: two upper cover plate joints, an upper cover plate, an upper solid plate, a heat exchange plate group, a lower solid plate, a lower cover plate and two lower cover plate joints arranged in sequence from top to bottom, the heat exchange plate group comprises a plurality of hot side heat exchange plates and a plurality of cold side heat exchange plates, the plurality of hot side heat exchange plates and the plurality of cold side heat exchange plates are alternately stacked in sequence in the vertical direction, and the grooves of the hot side heat exchange plates and the cold side heat exchange plates constitute a heat exchange channel for the hot fluid and the heat exchange channel for the cold fluid. The upper cover plate joint and the lower cover plate joint have the same structure, the upper cover plate and the lower cover plate have the same structure, and the upper solid plate and the lower solid plate have the same structure; a circular opening is respectively opened at a pair of top corners of the upper cover plate, a half-moon opening is respectively opened at the four top corners of the upper solid plate, a half-moon opening is respectively opened at the four top corners of the hot side heat exchange plate, a half-moon opening is respectively opened at the four top corners of the cold side heat exchange plate, and the lower A semi-lunar opening is respectively opened at the four top corners of the solid plate, and a circular opening is respectively opened at a pair of top corners of the lower cover plate; the four semi-lunar openings of the upper solid plate, the four semi-lunar openings on the hot side heat exchange plate, the four semi-lunar openings on the cold side heat exchange plate and the four semi-lunar openings of the lower solid plate are respectively arranged correspondingly and stacked into four channels with semi-lunar cross sections, the inlet and outlet of the hot fluid heat exchange channel are respectively communicated with the two first channels with semi-lunar cross sections at the first pair of diagonal corners, and the inlet and outlet of the cold fluid heat exchange channel are respectively communicated with the two second channels with semi-lunar cross sections at the second pair of diagonal corners; one end of the two connecting joints of the upper cover plate are respectively connected to the semi-lunar openings at the first pair of diagonal corners of the upper cover plate and communicate with the corresponding two first channels with semi-lunar cross sections, and one end of the two connecting joints of the lower cover plate are respectively connected to the semi-lunar openings at the second pair of diagonal corners of the lower cover plate and communicate with the corresponding two second channels with semi-lunar cross sections.

[0008] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that: the upper surface of each hot-side heat exchange plate has a plurality of hot-side microchannels arranged side by side to form a hot-side microchannel group, and the two ends of the hot-side microchannel are respectively communicated with two half-moon-shaped openings at one pair of diagonals, and a hot flow heat exchange channel is formed between the hot-side microchannel group on each hot-side heat exchange plate and the cold-side heat exchange plate or upper solid plate above it; the upper surface of each cold-side heat exchange plate has a plurality of cold-side microchannels arranged side by side to form a cold-side microchannel group, and the two ends of the cold-side microchannel are respectively communicated with two half-moon-shaped openings at another pair of diagonals, and a cold flow heat exchange channel is formed between the cold-side microchannel group on each cold-side heat exchange plate and the hot-side heat exchange plate above it.

[0009] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that: the outer contour shape and size of the upper cover plate, lower cover plate, upper solid plate, lower solid plate, hot side heat exchange plate and cold side heat exchange plate are the same; the hot side microchannels on the hot side heat exchange plate and the cold side microchannels on the cold side heat exchange plate are arranged in central symmetry.

[0010] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that: the hot side microchannel or the cold side microchannel is a sinusoidal corrugated channel, including an inlet section, a main heat exchange section and an outlet section connected in sequence, the inlet section and the main heat exchange section and the main heat exchange section and the outlet section are both set at 135°, the inlet section of the hot side microchannel and the outlet section of the cold side microchannel are set at 90°, the outlet section of the hot side microchannel and the inlet section of the cold side microchannel are set at 90°, the outlet section of the hot side microchannel coincides with the inlet section of the cold side microchannel, and the outlet section of the cold side microchannel coincides with the inlet section of the hot side microchannel.

[0011] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that the inlet section and the outlet section are sinusoidal corrugated channels, and the main heat exchange section is a sinusoidal corrugated channel.

[0012] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that the hot side microchannels on the hot side heat exchange plate and the cold side microchannels on the cold side heat exchange plate are obtained by 3D printing, etching or machining.

[0013] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that the channel arrangement direction of the hot side microchannel or the cold side microchannel is perpendicular to the flow direction of the main heat exchange section, and the upper surface of the hot side microchannel or the cold side microchannel can be flat or have a certain curvature, which is determined according to the 3D printing process.

[0014] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that: the upper solid plate, the heat exchange plate group and the lower solid plate are processed by 3D printing as the main part of the fuel and lubricating oil microchannel heat exchanger, the upper cover plate and the two upper cover plate joints, the lower cover plate and the two lower cover plate joints are processed by 3D printing, the upper surface of the upper solid plate and the upper cover plate surface are connected together by stir friction welding, and the lower surface of the lower solid plate and the lower cover plate surface are connected together by stir friction welding. In addition to stir friction welding, electron beam welding, vacuum diffusion welding and other welding methods can also be used to weld the upper and lower solid plates and the upper and lower cover plates.

[0015] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that: there are partition walls between the circular openings of the upper and lower cover plates and the outer contours of the upper and lower cover plates, between the semi-lunar openings of the upper and lower solid plates and the outer contours of the upper and lower solid plates, between the semi-lunar openings of the hot side heat exchange plate and the outer contour of the hot side heat exchange plate, between the semi-lunar openings of the cold side heat exchange plate and the outer contour of the cold side heat exchange plate, between the outermost groove of the main heat exchange section of the hot side heat exchange plate and the outer contour of the hot side heat exchange plate, and between the outermost groove of the main heat exchange section of the cold side heat exchange plate and the outer contour of the cold side heat exchange plate, and the thickness of the partition walls depends on the working pressure of the hot and cold fluids.

[0016] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that the main body of the heat exchanger is made of aluminum alloy or other low-density metals that can be used for 3D printing.

[0017] Furthermore, the high power-to-weight ratio fuel and lubricating oil microchannel heat exchanger is characterized in that the inlet section, main heat exchange section and outlet section of the hot side heat exchange plate and the cold side heat exchange plate are all effective heat exchange areas.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The main heat exchange section and the inlet and outlet sections of the present invention both use sinusoidal corrugated channels. Usually, when the fluid passes through the crests and troughs of the sinusoidal corrugated channel, longitudinal vortices will be generated, which is conducive to fluid mixing and momentum transfer, resulting in periodic interruption of the thermal boundary layer development process and inability to fully develop. This is an important reason for the enhanced heat transfer of the sinusoidal corrugated channel structure. However, for fuel and lubricating oil, high viscosity has an inhibitory effect on the formation of longitudinal vortices, but due to the periodic change of flow direction, the field synergy angle of velocity and temperature gradient is always small, and the effect of enhanced heat transfer is still very significant. In addition, on the cross section perpendicular to the flow direction, the centrifugal force of each local fluid micro-group is different due to different flow velocities, thereby forming a transverse secondary flow Dean vortex, which also has the effect of enhancing heat transfer. In addition, the resistance of the broken line channel and the sinusoidal corrugated channel under the same conditions was compared by simulation and other means, and the resistance of the sinusoidal corrugated channel was smaller.

[0020] 2. Most heat exchangers use straight channels in the inlet and outlet sections, which makes the heat exchange performance of the inlet and outlet sections lower than that of the main heat exchange section that adopts enhanced heat exchange means. The present invention still uses sinusoidal corrugated channels in the inlet and outlet sections, which improves the heat exchange performance of the inlet and outlet sections, thereby increasing the overall heat exchange performance of the heat exchanger.

[0021] 3. The plane layout of the inlet section and the outlet section in the present invention adopts an isosceles right triangle design, so that the heat exchange area of ​​the hot side heat exchange plate and the cold side heat exchange plate in the inlet section and the outlet section completely overlaps, reducing the ineffective heat exchange area, so that the weight of the heat exchanger can be reduced. In addition, unlike the main heat exchange section where the cold and hot fluids are exchanged in the most efficient countercurrent form, in the inlet section and the outlet section, the cold and hot fluids are exchanged in the form of a cross flow with a certain angle, and the heat exchange performance is reduced to a certain extent compared to the countercurrent. The isosceles right triangle design adopted in the inlet section and the outlet section of the present invention makes the crossflow angle of the cold and hot fluids 90°. The 90° crossflow is the heat exchange method with the highest heat exchange efficiency except the countercurrent form, which further improves the heat exchange performance of the heat exchanger in the inlet section and the outlet section, thereby improving the power-to-weight ratio of the heat exchanger.

[0022] 4. The material of the fuel oil heat exchanger in the present invention is aluminum alloy, which has a lower density than titanium alloy or stainless steel, which is beneficial to reducing the weight of the heat exchanger. The main part of the heat exchanger, that is, the heat exchange plate group and the solid plate are processed by 3D printing, and then the solid plate is welded to the upper and lower cover plates by stir friction welding. This processing method solves the problem that the microchannel is easily blocked when connecting the single-layer hot side heat exchange plate and the cold side heat exchange plate of aluminum alloy by stir friction welding. In addition, the main part of the heat exchanger adopts the processing method of 3D printing, and the structural strength is stronger than the part that adopts welding, and it can withstand higher pressure. In addition to stir friction welding, the upper and lower solid plates and the upper and lower cover plates can also be welded by electron beam welding, vacuum diffusion welding and other welding methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is an axonometric view of a fuel oil microchannel heat exchanger with a high power-to-weight ratio according to one embodiment of the present invention;

[0024] Figure 2 It is a top view of the upper and lower cover plates;

[0025] Figure 3 It is a top view of the upper and lower solid plates;

[0026] Figure 4 This is the axonometric view of the main body of the fuel and lubricating oil heat exchanger;

[0027] Figure 5 This is an axonometric view of the cover plate and joint;

[0028] Figure 6 It is a top view of the hot side heat exchange plate;

[0029] Figure 7 It is a top view of the cold side heat exchange plate;

[0030] Figure 8 A top view of the inlet section or outlet section and part of the main heat exchange section;

[0031] Fig. 9 A top view of the local details of the main heat exchange section.

[0032] Markings in the figure:

[0033] 1-upper cover plate joint; 2-upper cover plate; 3-upper solid plate; 4-hot side heat exchange plate; 4-1-semi-lunar opening of hot side heat exchange plate; 4-2-hot side microchannel; 5-cold side heat exchange plate; 5-1-semi-lunar opening of cold side heat exchange plate; 5-2 cold side microchannel; 6-lower solid plate; 7-lower cover plate; 8-lower cover plate joint; 9-circular opening; 10-semi-lunar opening of solid plate; 11-channel with a semi-lunar cross section; 11A-two first channels with a semi-lunar cross section at the first pair of diagonals; 11B-two second channels with a semi-lunar cross section at the second pair of diagonals; 12-inlet section; 13-main heat exchange section; 14-outlet section; 15-partition wall; 16-inlet and outlet of hot fluid heat exchange channel; 17-inlet and outlet of cold fluid heat exchange channel. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0035] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0036] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] See also Figure 1-9 According to an embodiment of the present invention, a fuel oil microchannel heat exchanger with a high power-to-weight ratio comprises: two upper cover plate joints 1, an upper cover plate 2, an upper solid plate 3, a heat exchange plate group, a lower solid plate 6, a lower cover plate 7 and two lower cover plate joints 8 arranged in sequence from top to bottom. The heat exchange plate group comprises a plurality of hot side heat exchange plates 4 and a plurality of cold side heat exchange plates 5, the plurality of hot side heat exchange plates 4 and the plurality of cold side heat exchange plates 5 are alternately stacked in sequence along the vertical direction, and the grooves of the hot side heat exchange plates 4 and the cold side heat exchange plates 5 constitute the heat exchange channels of the hot fluid and the heat exchange channels of the cold fluid; the upper cover plate joint 1 and the lower cover plate joint 8 are of the same structure, the upper cover plate 2 and the lower cover plate 7 are of the same structure, and the upper solid plate 3 and the lower solid plate 4 are of the same structure.

[0038] A circular opening 9 ( Figure 2 ).

[0039] The four top corners of the upper solid plate are respectively provided with a half-moon shaped opening 10 ( Figure 3 ).

[0040] The four corners of the hot side heat exchange plate 4 are respectively provided with a half-moon shaped opening 4-1 ( Figure 6 ).

[0041] The four corners of the cold side heat exchange plate 5 are respectively provided with a half-moon shaped opening 5-1 ( Figure 7 ).

[0042] A half-moon-shaped opening 10 is respectively formed at the four top corners of the lower solid plate 6 , and a circular opening 9 is respectively formed at a pair of top corners of the lower cover plate 7 .

[0043] The four half-moon openings 10 of the upper solid plate 3, the four half-moon openings 4-1 of the hot side heat exchange plate 4, the four half-moon openings 5-1 of the cold side heat exchange plate 5, and the four half-moon openings 10 of the lower solid plate 6 are respectively arranged correspondingly and stacked to form four channels 11 with half-moon cross sections ( Figure 4 ).

[0044] The inlet and outlet 16 of the hot fluid heat exchange channel are respectively communicated with the two first channels 11A with half-moon cross sections at the first pair of diagonals, and the inlet and outlet 17 of the cold fluid heat exchange channel are respectively communicated with the two second channels 11B with half-moon cross sections at the second pair of diagonals. One end of the two upper cover plate joints 1 is respectively connected to the half-moon openings at the first pair of diagonals of the upper cover plate 2 and communicates with the corresponding two first channels 11A with half-moon cross sections, and one end of the two lower cover plate joints 8 is respectively connected to the half-moon openings at the second pair of diagonals of the lower cover plate 7 and communicates with the corresponding two channels 11B with half-moon cross sections.

[0045] In this embodiment, the upper surface of each hot side heat exchange plate 4 has a plurality of hot side microchannels 4-2 arranged side by side to form a hot side microchannel group, and the two ends of the hot side microchannels 4-2 are respectively connected to the two half-moon-shaped openings 4-1 at one pair of diagonal points; a hot flow heat exchange channel is formed between the hot side microchannel group on each hot side heat exchange plate 4 and the cold side heat exchange plate 5 or the upper solid plate 3 above it; the upper surface of each cold side heat exchange plate 5 has a plurality of cold side microchannels 5-2 arranged side by side to form a cold side microchannel group, and the two ends of the cold side microchannels 5-2 are respectively connected to the two half-moon-shaped openings 5-1 at another pair of diagonal points, and a cold flow heat exchange channel is formed between the cold side microchannel group on each cold side heat exchange plate 5 and the hot side heat exchange plate 4 above it. Through such an arrangement, it is ensured that the flow areas of the cold and hot fluids overlap and the heat exchange purpose is achieved, and the hot side heat exchange plates 4 and the cold side heat exchange plates 5 are arranged alternately to ensure the uniformity and efficiency of heat exchange.

[0046] In this embodiment, the upper cover plate 2, the lower cover plate 7, the upper solid plate 3, the lower solid plate 6, the hot side heat exchange plate 4 and the cold side heat exchange plate 5 have the same outer contour shape and size; the hot side microchannel 4-2 on the hot side heat exchange plate 4 and the cold side microchannel 5-2 on the cold side heat exchange plate 5 are arranged in a central symmetric manner. The consistency of the outer contour shape and size facilitates the alignment of the heat exchanger body and the cover plate during welding, and the central symmetric arrangement makes the total length of each channel consistent, so that the cold flow heat exchange channel and the hot flow heat exchange channel have the same flow performance.

[0047] In this embodiment, the hot side microchannel 4-2 or the cold side microchannel 5-2 are both sinusoidal corrugated channels, including an inlet section 12, a main heat exchange section 13 and an outlet section 14 connected in sequence, and the inlet section 12 and the main heat exchange section 13 and the main heat exchange section 13 and the outlet section 14 are both arranged at 135°; from the perspective of the upper surface of the hot side heat exchange plate 4, the main heat exchange section 13 of the hot side microchannel 4-2 and the main heat exchange section 13 of the cold side microchannel 5-2 are arranged at 135°. The inlet section 12 of the hot side microchannel 4-2 and the outlet section 14 of the cold side microchannel 5-2 are arranged at 90°, the outlet section 14 of the hot side microchannel 4-2 and the inlet section 12 of the cold side microchannel 5-2 are arranged at 90°, the outlet section 15 of the hot side microchannel 4-2 and the inlet section 12 of the cold side microchannel 5-2 are overlapped, and the outlet section 14 of the cold side microchannel 5-2 and the inlet section 12 of the hot side microchannel 4-2 are overlapped. The main heat exchange section adopts the form of counterflow to maximize the heat exchange efficiency of the main heat exchange section. Since the inlet and outlet sections need to be connected to the inlet and outlet, they must be in the form of cross flow due to structural obstacles. The heat exchange performance is reduced compared to the counterflow. Therefore, although the overlapping area in the inlet and outlet sections can exchange heat, it is an inefficient heat exchange area. The angle of cross flow will further affect the heat exchange efficiency of the inlet and outlet sections. The cross flow angle of 90° is the cross flow angle of hot and cold fluids with the highest heat exchange efficiency except counterflow. Therefore, a 90° cross flow is adopted in the inlet and outlet sections to maximize the heat exchange efficiency of the main heat exchange section, the inlet section and the outlet section, which is beneficial to improving the power-to-weight ratio of the heat exchanger. In addition, since the inlet and outlet are arranged on both sides of the heat exchanger end, there is still a part of non-overlapping area at the traditional heat exchanger end. This part of the area does not play a role in the heat exchange between the cold and hot fluids, but increases the weight of the heat exchanger, which is an invalid heat exchange area. In the present invention, the inlet section area of ​​the hot side heat exchange plate is overlapped with the outlet section area of ​​the cold side heat exchange plate, and the outlet section area of ​​the hot side heat exchange plate is overlapped with the inlet section area of ​​the cold side heat exchange plate, thereby reducing the invalid heat exchange area as much as possible, thereby reducing the weight of the heat exchanger.

[0048] In this embodiment, Figure 6-9 As shown, the inlet section 12 and the outlet section 14 are sinusoidal corrugated channels, and the main heat exchange section 13 is a sinusoidal corrugated channel. The sinusoidal corrugated channels of the inlet section, the main heat exchange section and the outlet section can destroy the thermal boundary layer of the fuel oil during the flow process, enhance the heat exchange effect, and help improve the power-to-weight ratio of the heat exchanger. In addition, the use of corrugated channels in the inlet section and the outlet section improves the heat exchange efficiency of the inlet section and the outlet section compared to the straight channel, which is conducive to improving the power-to-weight ratio of the heat exchanger.

[0049] In a specific embodiment of the present invention, the hot side microchannel 4 - 2 on the hot side heat exchange plate 4 and the cold side microchannel 5 - 2 on the cold side heat exchange plate 5 are obtained by 3D printing.

[0050] In a specific embodiment of the present invention, the channel arrangement direction of the hot side microchannel 4-2 or the cold side microchannel 5-2 is perpendicular to the direction of fluid flow in the main heat exchange section 13, and the upper surface of the hot side microchannel 4-2 or the cold side microchannel 5-2 is flat. The flat upper surface increases the cross-sectional area of ​​the microchannel and reduces the roughness, which is conducive to reducing the resistance of the heat exchanger.

[0051] In a specific embodiment of the present invention, the upper solid plate 3, the heat exchange plate group and the lower solid plate 6 are processed by 3D printing as the main part of the fuel and lubricating oil microchannel heat exchanger, the upper cover plate 2 and the two upper cover plate joints 1, the lower cover plate 7 and the two lower cover plate joints 8 are processed by 3D printing, the upper surface of the upper solid plate 3 is connected to the surface of the upper cover plate 2 by stir friction welding, and the lower surface of the lower solid plate 6 is connected to the surface of the lower cover plate 7 by stir friction welding.

[0052] In a specific embodiment of the present invention, there is a partition wall 15 between the circular openings 9 of the upper and lower cover plates and the outer contours of the upper and lower cover plates, between the semi-lunar openings 10 of the upper and lower solid plates and the outer contours of the upper and lower solid plates, between the semi-lunar openings 4-1 of the hot side heat exchange plate 4 and the outer contour of the hot side heat exchange plate, between the semi-lunar openings 5-1 of the cold side heat exchange plate 5 and the outer contour of the cold side heat exchange plate, between the outermost groove of the main heat exchange section of the hot side heat exchange plate 4 and the outer contour of the hot side heat exchange plate, and between the outermost groove of the main heat exchange section of the cold side heat exchange plate 5 and the outer contour of the cold side heat exchange plate. The thickness of the partition wall is 5 mm and can withstand a working pressure of 6 MPa.

[0053] In a specific embodiment according to the present invention, the material of the main body of the heat exchanger is AlSi10Mg.

[0054] In a specific embodiment according to the present invention, the inlet section, the main heat exchange section and the outlet section of the hot side heat exchange plate and the cold side heat exchange plate are all effective heat exchange areas.

[0055] In a specific embodiment of the present invention, the heat exchanger has a semi-lunar opening, and sharp corners at the inlet and outlet sections are chamfered to prevent stress concentration and reduce resistance during flow.

[0056] In a specific embodiment of the present invention, the hot side microchannel of the hot side heat exchange plate and the cold side microchannel of the cold side heat exchange plate have the same channel size, channel width 0.5 mm, channel height 0.5 mm, fin thickness 0.5 mm, and the entire hot side heat exchange plate or the cold side heat exchange plate is 1 mm thick.

[0057] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. A high power-to-weight ratio fuel oil microchannel heat exchanger, characterized in that include: The two upper cover plate joints (1), the upper cover plate (2), the upper solid plate (3), the heat exchange plate group, the lower solid plate (6), the lower cover plate (7) and the two lower cover plate joints (8) are arranged in sequence from top to bottom. in: The heat exchange plate group comprises a plurality of hot side heat exchange plates (4) and a plurality of cold side heat exchange plates (5), wherein the plurality of hot side heat exchange plates (4) and the plurality of cold side heat exchange plates (5) are stacked alternately in sequence in a vertical direction, and the hot side heat exchange plates (4) and the cold side heat exchange plates (5) have groove portions, and the groove portions constitute heat exchange channels for hot fluids and heat exchange channels for cold fluids; The upper cover plate joint (1) and the lower cover plate joint (8) have the same structure, the upper cover plate (2) and the lower cover plate (7) have the same structure, and the upper solid plate (3) and the lower solid plate (4) have the same structure; A circular opening (9) is respectively provided at a pair of top corners of the upper cover plate (2), a half-moon opening (10) is respectively provided at the four top corners of the upper solid plate, a half-moon opening (4-1) is respectively provided at the four top corners of the hot side heat exchange plate (4), a half-moon opening (5-1) is respectively provided at the four top corners of the cold side heat exchange plate (5), a half-moon opening (10) is respectively provided at the four top corners of the lower solid plate (6), and a circular opening (9) is respectively provided at a pair of top corners of the lower cover plate (7); The four half-moon-shaped openings (10) of the upper solid plate (3), the four half-moon-shaped openings (4-1) of the hot side heat exchange plate (4), the four half-moon-shaped openings (5-1) of the cold side heat exchange plate (5), and the four half-moon-shaped openings (10) of the lower solid plate (6) are respectively arranged in a corresponding manner and are respectively stacked to form four channels (11) with half-moon-shaped cross sections; the inlet and outlet (16) of the hot fluid heat exchange channel are respectively communicated with the two first channels (11A) with half-moon-shaped cross sections at the first pair of diagonal corners; and the inlet and outlet (17) of the cold fluid heat exchange channel are respectively communicated with the two second channels (11B) with half-moon-shaped cross sections at the second pair of diagonal corners; One end of the two upper cover plate joints (1) is respectively connected to the semi-lunar openings at the first pair of diagonal corners of the upper cover plate (2) and communicates with two corresponding first channels (11A) with a semi-lunar cross section, and one end of the two lower cover plate joints (8) is respectively connected to the semi-lunar openings at the second pair of diagonal corners of the lower cover plate (7) and communicates with two corresponding second channels (11B) with a semi-lunar cross section.

2. The high power-to-weight ratio fuel and oil microchannel heat exchanger according to claim 1, characterized in that: The upper surface of each hot side heat exchange plate (4) has a plurality of hot side microchannels (4-2) arranged side by side to form a hot side microchannel group, the two ends of the hot side microchannel (4-2) are respectively connected to two half-moon-shaped openings (4-1) located at a pair of diagonal positions, and a heat flow heat exchange channel is formed between the hot side microchannel group on each hot side heat exchange plate (4) and the cold side heat exchange plate (5) or the upper solid plate (3) above it; The upper surface of each cold side heat exchange plate (5) is provided with a plurality of cold side microchannels (5-2) arranged side by side to form a cold side microchannel group, and the two ends of the cold side microchannels (5-2) are respectively connected to the two half-moon-shaped openings (5-1) at the other pair of diagonal positions, and a cold flow heat exchange channel is formed between the cold side microchannel group on each cold side heat exchange plate (5) and the hot side heat exchange plate (4) above it.

3. The high power-to-weight ratio fuel and oil microchannel heat exchanger according to claim 1, characterized in that: The upper cover plate (2), the lower cover plate (7), the upper solid plate (3), the lower solid plate (6), the hot side heat exchange plate (4) and the cold side heat exchange plate (5) have the same outer contour shape and size; The hot side microchannels (4-2) on the hot side heat exchange plate (4) and the cold side microchannels (5-2) on the cold side heat exchange plate (5) are arranged in a centrally symmetrical manner; The hot side microchannel (4-2) or the cold side microchannel (5-2) are both sinusoidal corrugated channels, comprising an inlet section (12), a main heat exchange section (13) and an outlet section (14) connected in sequence, the inlet section (12) and the main heat exchange section (13) and the main heat exchange section (13) and the outlet section (14) are arranged at 135 degrees, and from the perspective of the upper surface of the hot side heat exchange plate (4), the main heat exchange section (13) of the hot side microchannel (4-2) and the main heat exchange section (13) of the cold side microchannel (5-2) overlap, and the inlet section (12) of the hot side microchannel (4-2) and the outlet section (14) are arranged at 135 degrees. The outlet sections (15) of the channels (5-2) are arranged at 90 degrees to each other, the outlet section (15) of the hot side microchannel (4-2) and the inlet section (12) of the cold side microchannel (5-2) are arranged at 90 degrees to each other, the outlet section (15) of the hot side microchannel (4-2) overlaps with the inlet section (12) of the cold side microchannel (5-2), and the outlet section (14) of the cold side microchannel (5-2) overlaps with the inlet section (12) of the hot side microchannel (4-2); the inlet section (12) and the outlet section (14) are sinusoidal corrugated channels, and the main heat exchange section (13) is a sinusoidal corrugated channel.

4. The high power-to-weight ratio fuel and oil microchannel heat exchanger according to claim 2, characterized in that: The hot side microchannels (4-2) on the hot side heat exchange plate (4) and the cold side microchannels (5-2) on the cold side heat exchange plate (5) are obtained by 3D printing, etching or machining.

5. The high power-to-weight ratio fuel and oil microchannel heat exchanger according to claim 1, characterized in that: The channel arrangement direction of the hot side microchannel (4-2) or the cold side microchannel (5-2) is perpendicular to the direction of fluid flow in the main heat exchange section (13), and the upper surface of the hot side microchannel (4-2) or the cold side microchannel (5-2) can be flat or have a certain curvature, which is determined according to the 3D printing process.

6. The high power-to-weight ratio fuel and oil microchannel heat exchanger according to claim 1, characterized in that: The upper solid plate (3), the heat exchange plate group and the lower solid plate (6) are processed by 3D printing as the main part of the fuel oil microchannel heat exchanger. The upper cover plate (2) and the two upper cover plate joints (1), the lower cover plate (7) and the two lower cover plate joints (8) are processed by 3D printing. The upper surface of the upper solid plate (3) and the surface of the upper cover plate (2) are connected together by stir friction welding. The lower surface of the lower solid plate (6) and the surface of the lower cover plate (7) are connected together by stir friction welding. In addition to stir friction welding, the upper and lower solid plates and the upper and lower cover plates can also be welded by electron beam welding, vacuum diffusion welding and other welding methods.

7. The high power-to-weight ratio fuel and oil microchannel heat exchanger according to claim 2, characterized in that: There is a partition wall (15) between the circular openings (9) of the upper and lower cover plates and the outer contours of the upper and lower cover plates, between the half-moon openings (10) of the upper and lower solid plates and the outer contours of the upper and lower solid plates, between the half-moon opening (4-1) of the hot side heat exchange plate (4) and the outer contour of the hot side heat exchange plate, between the half-moon opening (5-1) of the cold side heat exchange plate (5) and the outer contour of the cold side heat exchange plate, between the outermost groove of the main heat exchange section of the hot side heat exchange plate (4) and the outer contour of the hot side heat exchange plate, and between the outermost groove of the main heat exchange section of the cold side heat exchange plate (5) and the outer contour of the cold side heat exchange plate, and the thickness of the partition wall depends on the working pressure of the hot and cold fluids.

8. The high power-to-weight ratio fuel and oil microchannel heat exchanger according to claim 1, characterized in that: The main body of the heat exchanger is made of aluminum alloy or other metals with low density that can be used for 3D printing.

9. The high power-to-weight ratio fuel and oil microchannel heat exchanger according to claim 3, characterized in that: The inlet section, main heat exchange section and outlet section of the hot side heat exchange plate and the cold side heat exchange plate are all effective heat exchange areas.

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