High power-weight ratio fuel oil lubricating oil microchannel heat exchanger

Abstract

The application discloses a high-power-weight-ratio fuel oil and lubricating oil micro-channel heat exchanger, which 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, and the heat exchange plate group comprises heat exchange plates on a hot side and heat exchange plates on a cold side which are arranged alternately in sequence. The sinusoidal wave-shaped groove portions of the heat exchange plates on the hot side and the heat exchange plates on the cold side form heat exchange channels for hot fluid and cold fluid, and the cold and hot fluids exchange heat in a countercurrent form in a main heat exchange section in the middle of the heat exchanger; the inlet section and the outlet section of the end section of the heat exchanger adopt a 90-degree cross flow and a completely overlapping design, so that the invalid heat exchange area is reduced, and the heat exchange efficiency of the end section of the heat exchanger is improved. The material of the heat exchanger is AlSi10Mg aluminum alloy, and the heat exchanger is assembled by adopting a 3D printing and friction stir welding combination mode. The fuel oil and lubricating oil micro-channel heat exchanger provided by the application can realize high power-weight ratio and low resistance at the same time, and has high pressure-bearing capacity.

Description

TECHNICAL FIELD

[0001] The present application relates to a high power-weight ratio fuel-oil micro-channel heat exchanger. BACKGROUND

[0002] In high-speed operating aero-engines, both bearings and gears need continuous and efficient lubrication of oil, and a large amount of heat is generated in the process of rotation and transmission, plus the heat conduction of the engine body, the temperature of the oil will rise significantly, if the temperature is too high, the viscosity and acid value will increase, and even coking phenomenon will occur, thereby threatening the safe operation of the engine. The fuel-oil heat exchanger uses the fuel of the engine as a cold source to effectively cool the engine oil and dissipate the heat load of the lubrication process, so as to ensure that the oil always works in a safe temperature range within the flight envelope.

[0003] At present, the traditional aviation fuel-oil heat exchanger mostly adopts a shell-and-tube heat exchanger. To improve the heat exchange performance of the shell-and-tube heat exchanger, it is usually achieved by increasing the number of channels or lengthening the channel length, but such measures will 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 exchange performance. Patent CN110043342 A discloses an aero-engine high-pressure fuel-oil radiator, which adopts a double-core, multi-flow shell-and-tube heat exchange structure, the heat exchange capacity is 72.6 kW, the weight is 16.9 kg, and the power-weight ratio is only 4.3 kW / kg. In this special application of aero-engines, flow resistance and weight are equally important indicators as heat exchange capacity, and blindly or preferentially improving heat exchange capacity is easy to cause excessive weight, and for high-viscosity fluids such as fuel and oil, the resistance will also increase significantly. Therefore, to achieve an ultra-high power-weight ratio (such as 15 kW / kg or more) and a low resistance, the traditional fuel-oil heat exchanger form cannot meet the requirements.

[0004] To achieve an ultra-high power-weight ratio, a compact and strong heat exchange structure needs to be adopted, and all heat exchange areas need to be utilized as much as possible. Chinese patent application CN114993078 A discloses a micro-channel heat exchanger suitable for high-viscosity oil working medium, the heat exchanger adopts S30408 austenitic stainless steel or titanium alloy, and the heat exchange core adopts a zigzag micro-channel, which can effectively improve the heat exchange performance. However, part of the area in the inlet section and the outlet section is invalid heat exchange area, which will increase the weight of the fuel-oil heat exchanger, but is not beneficial to heat exchange, thereby reducing the power-weight ratio, and the inlet section and the outlet section do not adopt the 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 place is low. In addition, the flow resistance of the zigzag channel of the core will be relatively large. More importantly, the density of S30408 austenitic stainless steel and titanium alloy is relatively large, which is not conducive to improving the power-weight ratio of the fuel-oil heat exchanger.

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

[0006] The purpose of the present application is to provide a high power-to-weight ratio fuel oil lubricating oil heat exchanger, which uses a corrugated microchannel to significantly improve the heat exchanger performance without significantly increasing the weight and resistance of the heat exchanger, achieving high power-to-weight ratio and low resistance of the heat exchanger.

[0007] Technical scheme: The purpose of the present application is achieved by the following technical scheme. The high power-to-weight ratio fuel oil lubricating oil microchannel heat exchanger of the present application 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 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 the vertical direction, and the groove parts of the hot side heat exchange plates and the cold side heat exchange plates constitute heat exchange channels for hot fluid and cold fluid; the upper cover plate joint and the lower cover plate joint are the same structure, the upper cover plate and the lower cover plate are the same structure, and the upper solid plate and the lower solid plate are the same structure; a pair of top corners of the upper cover plate are respectively provided with a circular opening, four top corners of the upper solid plate are respectively provided with a half-moon shaped opening, four top corners of the hot side heat exchange plate are respectively provided with a half-moon shaped opening, four top corners of the cold side heat exchange plate are respectively provided with a half-moon shaped opening, four top corners of the lower solid plate are respectively provided with a half-moon shaped opening, and a pair of top corners of the lower cover plate are respectively provided with a circular opening; the four half-moon shaped openings of the upper solid plate, the four half-moon shaped openings on the hot side heat exchange plate, the four half-moon shaped openings on the cold side heat exchange plate and the four half-moon shaped openings of the lower solid plate are respectively correspondingly arranged and stacked into four channels with a half-moon shaped cross section, the inlets and outlets of the hot fluid heat exchange channels are respectively communicated with the two first channels with a half-moon shaped cross section at the first pair of opposite corners, and the inlets and outlets of the cold fluid heat exchange channels are respectively communicated with the two second channels with a half-moon shaped cross section at the second pair of opposite corners; one end of the two connecting joints of the upper cover plate is respectively connected to the half-moon shaped openings at the first pair of opposite corners of the upper cover plate and communicated with the corresponding two first channels with a half-moon shaped cross section, and one end of the two connecting joints of the lower cover plate is respectively connected to the half-moon shaped openings at the second pair of opposite corners of the lower cover plate and communicated with the corresponding two second channels with a half-moon shaped cross section.

[0008] Further, the high power-weight ratio fuel oil lubricating oil micro-channel heat exchanger is characterized in that: the upper surface of each heat side heat exchange plate is provided with a plurality of heat side micro-channels arranged side by side and forming a heat side micro-channel group, and the two ends of the heat side micro-channel are communicated with the two half-moon-shaped openings at one pair of diagonal positions, respectively; the heat side micro-channel group on each heat side heat exchange plate and the cold side heat exchange plate or the upper solid plate thereabove form a heat flow heat exchange channel; the upper surface of each cold side heat exchange plate is provided with a plurality of cold side micro-channels arranged side by side and forming a cold side micro-channel group, and the two ends of the cold side micro-channel are communicated with the two half-moon-shaped openings at another pair of diagonal positions, respectively; and the cold side micro-channel group on each cold side heat exchange plate and the heat side heat exchange plate thereabove form a cold flow heat exchange channel.

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

[0010] Further, the high power-weight ratio fuel oil lubricating oil micro-channel heat exchanger is characterized in that: the heat side micro-channels or the cold side micro-channels are sine wave-shaped channels, 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 arranged at 135°, the inlet section of the heat side micro-channel and the outlet section of the cold side micro-channel are arranged at 90°, the outlet section of the heat side micro-channel and the inlet section of the cold side micro-channel are arranged at 90°, the outlet section of the heat side micro-channel coincides with the inlet section of the cold side micro-channel, and the outlet section of the cold side micro-channel coincides with the inlet section of the heat side micro-channel.

[0011] Further, the high power-weight ratio fuel oil lubricating oil micro-channel heat exchanger is characterized in that: the inlet section and the outlet section are sine wave-shaped channels, and the main heat exchange section is a sine wave-shaped channel.

[0012] Further, the high power-weight ratio fuel oil lubricating oil micro-channel heat exchanger is characterized in that: the heat side micro-channels on the heat side heat exchange plate and the cold side micro-channels on the cold side heat exchange plate are obtained by 3D printing, etching or machining.

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

[0014] Further, the high power-to-weight ratio fuel-oil micro-channel heat exchanger is characterized in that the upper solid plate, the heat exchanger plate group and the lower solid plate are processed by 3D printing as the main part of the fuel-oil micro-channel heat exchanger, and 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 is connected with the surface of the upper cover plate by friction stir welding, and the lower surface of the lower solid plate is connected with the surface of the lower cover plate by friction stir welding, and in addition to friction stir welding, electron beam welding, vacuum diffusion welding and other welding forms can be used to weld the upper and lower solid plates and the upper and lower cover plates.

[0015] Further, the high power-to-weight ratio fuel-oil micro-channel heat exchanger is characterized in that the circular openings of the upper and lower cover plates and the outer contours of the upper and lower cover plates, the half-moon openings of the upper and lower solid plates and the outer contours of the upper and lower solid plates, the half-moon openings of the hot side heat exchanger plates and the outer contours of the hot side heat exchanger plates, the half-moon openings of the cold side heat exchanger plates and the outer contours of the cold side heat exchanger plates, the outermost side grooves of the main heat exchange sections of the hot side heat exchanger plates and the outer contours of the hot side heat exchanger plates, and the outermost side grooves of the main heat exchange sections of the cold side heat exchanger plates and the outer contours of the cold side heat exchanger plates have an interwall, and the thickness of the interwall depends on the working pressure of the hot and cold fluids.

[0016] Further, the high power-to-weight ratio fuel-oil micro-channel heat exchanger is characterized in that the main part of the heat exchanger is made of aluminum alloy or other metals with small density that can be used for 3D printing.

[0017] Further, the high power-to-weight ratio fuel-oil micro-channel heat exchanger is characterized in that the inlet sections, the main heat exchange sections and the outlet sections of the hot side heat exchanger plates and the cold side heat exchanger plates are all effective heat exchange areas.

[0018] Compared with the prior art, the high power-to-weight ratio fuel-oil micro-channel heat exchanger has the following beneficial effects:

[0019] 1. The main heat exchange sections and the inlet and outlet sections in the application adopt sinusoidal corrugated channels, generally, the fluid will generate longitudinal vortex when passing through the wave crest and wave trough of the sinusoidal corrugated channel, which is conducive to fluid mixing and momentum transmission, and causes the periodic interruption of the development process of the thermal boundary layer and the failure to fully develop, which is an important reason for the structure of the sinusoidal corrugated channel to strengthen heat transfer. However, for fuel and lubricating oil, high viscosity has an inhibitory effect on the formation of longitudinal vortex, 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 heat transfer enhancement is still very significant. In addition, in the cross section perpendicular to the flow direction, local fluid clusters are subjected to different centrifugal forces due to different flow rates, thereby forming transverse secondary flow Dean vortices, which also play a role in strengthening heat transfer. In addition, the resistance of the sinusoidal corrugated channel is smaller than that of the polyline channel and the sinusoidal corrugated channel under the same conditions through simulation and other means.

[0020] 2. Most heat exchangers adopt straight channel form in the inlet section and outlet section, which will make the heat exchange performance of the inlet section and outlet section lower than that of the main heat exchange section which adopts heat exchange enhancement means. The present application still adopts sinusoidal corrugated channel in the inlet section and outlet section, which improves the heat exchange performance of the inlet section and outlet section, thereby increasing the overall heat exchange performance of the heat exchanger.

[0021] 3. The plane layout of the inlet section and outlet section in the present application adopts isosceles right triangle design, which makes the heat exchange area of the hot side heat exchange plate and the cold side heat exchange plate completely coincide in the inlet section and outlet section, reduces the invalid heat exchange area, and enables the weight of the heat exchanger to be reduced. In addition, unlike the cold and hot fluids in the main heat exchange section which exchange heat in the most efficient counterflow form, in the inlet section and outlet section, the cold and hot fluids exchange heat in a certain crossflow form, and the heat exchange performance is reduced compared with the counterflow. The isosceles right triangle design of the inlet section and outlet section in the present application makes the crossflow angle of the cold and hot fluids 90°, and 90° crossflow is the highest heat exchange mode except the counterflow form, which further improves the heat exchange performance of the heat exchanger in the inlet section and outlet section, thereby improving the power-to-weight ratio of the heat exchanger.

[0022] 4. The material of the fuel oil lubricating oil heat exchanger in the present application is aluminum alloy, which has lower density than titanium alloy or stainless steel, and is conducive to reducing the weight of the heat exchanger. The main part of the heat exchanger, i.e. the heat exchange plate group and the solid plate, is processed by 3D printing integration, and then the solid plate is welded to the upper and lower cover plates by friction stir welding to form an integral body. This processing method solves the problem that only using friction stir welding to connect the single-layer hot side heat exchange plate and the cold side heat exchange plate made of aluminum alloy is prone to cause micro-channel blockage. Moreover, the main part of the heat exchanger adopts 3D printing processing method, and the structural strength is stronger than that of the welded part, which can withstand higher pressure. In addition to friction stir welding, electron beam welding, vacuum diffusion welding and other welding forms can also be used to weld the upper and lower solid plates to the upper and lower cover plates. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is the isometric view of the high power-to-weight ratio fuel oil lubricating oil micro-channel heat exchanger according to an embodiment of the present application;

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

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

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

[0027] Figure 5 is the isometric view of the cover plate and the joint;

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

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

[0030] Figure 8 is a top view of the inlet section or outlet section and part of the main heat transfer section;

[0031] Figure 9 is a top view of a detail of the main heat transfer section.

[0032] Reference signs in the figures:

[0033] 1 - upper cover plate joint; 2 - upper cover plate; 3 - upper solid plate; 4 - hot side heat transfer plate; 4-1 - hot side heat transfer plate half moon shaped opening; 4-2 - hot side micro channel; 5 - cold side heat transfer plate; 5-1 - cold side heat transfer plate half moon shaped opening; 5-2 cold side micro channel; 6 - lower solid plate; 7 - lower cover plate; 8 - lower cover plate joint; 9 - circular opening; 10 - solid plate half moon shaped opening; 11 - half moon shaped cross section channel; 11A - first pair of two half moon shaped cross section first channels at opposite corners; 11B - second pair of two half moon shaped cross section second channels at opposite corners; 12 - inlet section; 13 - main heat transfer section; 14 - outlet section; 15 - partition wall; 16 - inlet and outlet of hot fluid heat transfer channel; 17 - inlet and outlet of cold fluid heat transfer channel. DETAILED DESCRIPTION

[0034] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments with reference to the drawings in the embodiments of the present application. The following embodiments are used to explain the present application, but not to limit the scope of the present application.

[0035] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0036] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0037] Please refer toFigures 1-9 The high-power-weight-ratio fuel-oil microchannel heat exchanger according to one embodiment of the present application comprises two upper cover plate joints 1, an upper cover plate 2, an upper solid plate 3, a heat exchange plate set, 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 set comprises a plurality of hot-side heat exchange plates 4 and a plurality of cold-side heat exchange plates 5, which are alternately stacked in sequence along the vertical direction, and the recessed portions of the hot-side heat exchange plates 4 and the cold-side heat exchange plates 5 form the heat exchange channels for the hot fluid and 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 pair of circular openings 9 are respectively formed at the top corners of the upper cover plate 2. Figure 2

[0039] A pair of semilunar openings 10 are respectively formed at the top corners of the upper solid plate. Figure 3

[0040] A pair of semilunar openings 4-1 are respectively formed at the top corners of the hot-side heat exchange plate 4. Figure 6

[0041] A pair of semilunar openings 5-1 are respectively formed at the top corners of the cold-side heat exchange plate 5. Figure 7

[0042] A pair of semilunar openings 10 are respectively formed at the top corners of the lower solid plate 6, and a pair of circular openings 9 are respectively formed at the top corners of the lower cover plate 7.

[0043] The four semilunar openings 10 of the upper solid plate 3, the four semilunar openings 4-1 of the hot-side heat exchange plate 4, the four semilunar openings 5-1 of the cold-side heat exchange plate 5 and the four semilunar openings 10 of the lower solid plate 6 are respectively arranged correspondingly and stacked into four semilunar cross-section channels 11. Figure 4

[0044] The inlets and outlets 16 of the hot fluid heat exchange channels are respectively communicated with the two semilunar cross-section first channels 11A of the first pair of opposite corners, and the inlets and outlets 17 of the cold fluid heat exchange channels are respectively communicated with the two semilunar cross-section second channels 11B of the second pair of opposite corners. One end of each of the two upper cover plate joints 1 is connected to the semilunar openings of the first pair of opposite corners of the upper cover plate 2 and communicated with the corresponding two semilunar cross-section first channels 11A, and one end of each of the two lower cover plate joints 8 is connected to the semilunar openings of the second pair of opposite corners of the lower cover plate 7 and communicated with the corresponding two semilunar cross-section second channels 11B. ​​​​​

[0045] In the 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 and forming a hot-side microchannel group, and the two ends of each hot-side microchannel 4-2 are communicated with two half-moon shaped openings 4-1 at a pair of opposite corners; 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 form a hot flow heat exchange channel; the upper surface of each cold-side heat exchange plate 5 has a plurality of cold-side microchannels 5-2 arranged side by side and forming a cold-side microchannel group, and the two ends of each cold-side microchannel 5-2 are communicated with two half-moon shaped openings 5-1 at another pair of opposite corners; the cold-side microchannel group on each cold-side heat exchange plate 5 and the hot-side heat exchange plate 4 above it form a cold flow heat exchange channel. Through such arrangement, the flow areas of the cold and hot fluids are overlapped to achieve the heat exchange purpose, 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 the heat exchange.

[0046] In the 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 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 central symmetry. The consistent outer contour shape and size facilitate the alignment of the heat exchanger body and the cover plate during welding, and the central symmetry 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 the embodiment, the hot-side microchannel 4-2 or the cold-side microchannel 5-2 is a sinusoidal corrugated channel, which comprises 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 outlet section 14 are arranged at an angle of 135° with the main heat exchange section 13. From the perspective of the vertical 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 coincide, 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 an angle of 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 an angle of 90°, the outlet section 15 of the hot-side microchannel 4-2 and the inlet section 12 of the cold-side microchannel 5-2 coincide, and the outlet section 14 of the cold-side microchannel 5-2 and the inlet section 12 of the hot-side microchannel 4-2 coincide. The countercurrent form of the main heat exchange section can make the heat exchange efficiency of the main heat exchange section reach the highest, while the inlet section and the outlet section must be in the form of cross flow due to the structural obstruction caused by the connection with the inlet and outlet, and the heat exchange performance is reduced compared with the countercurrent, therefore, the overlapping area in the inlet section and the outlet section can be used for heat exchange, but it is a low-efficiency heat exchange area, and the cross flow angle further affects the heat exchange efficiency of the inlet section and the outlet section, and the cross flow angle of 90° is the highest heat exchange efficiency of the cold and hot fluids except for the countercurrent, therefore, the inlet section and the outlet section are in the form of cross flow at an angle of 90°, so that the heat exchange efficiency of the main heat exchange section, the inlet section and the outlet section reaches the highest, which is beneficial to improve the power-to-weight ratio of the heat exchanger. In addition, since the inlet and outlet are arranged on both sides of the end of the heat exchanger, there is still a part of the area that does not overlap at the end of the traditional heat exchanger, which does not play a role in the heat exchange of the cold and hot fluids, but increases the weight of the heat exchanger, which is an invalid heat exchange area, and the inlet section area of the hot-side heat exchange plate and the outlet section area of the cold-side heat exchange plate are overlapped in the application, and the outlet section area of the hot-side heat exchange plate and the inlet section area of the cold-side heat exchange plate are overlapped, so as to reduce the invalid heat exchange area as much as possible, thereby reducing the weight of the heat exchanger.

[0048] In the embodiment, as shown in FIG. 1, Figures 6-9 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 and the lubricating oil in the flow process, strengthen the heat exchange effect, and be beneficial to improve the power-to-weight ratio of the heat exchanger. Moreover, the corrugated channels are adopted in the inlet section and the outlet section, which improves the heat exchange efficiency of the inlet section and the outlet section compared with the straight channels, and is beneficial to improve the power-to-weight ratio of the heat exchanger.

[0049] In a specific embodiment according to the application, 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 one embodiment of the application, the channel arrangement direction of the hot side microchannel 4-2 or the cold side microchannel 5-2 is perpendicular to the fluid flow direction of 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 beneficial to reduce the resistance of the heat exchanger.

[0051] In one embodiment of the application, 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 lubricating oil microchannel heat exchanger, and 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 friction stir welding, and the lower surface of the lower solid plate 6 is connected to the surface of the lower cover plate 7 by friction stir welding.

[0052] In one embodiment of the application, there is an interwall 15 between the circular opening 9 of the upper and lower cover plates and the outer contour of the upper and lower cover plates, between the half-moon-shaped opening 10 of the upper and lower solid plates and the outer contour of the upper and lower solid plates, between the half-moon-shaped 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-shaped 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. The thickness of the interwall is 5mm, which can withstand a working pressure of 6MPa.

[0053] In one embodiment of the application, the material of the main part of the heat exchanger is AlSi10Mg.

[0054] In one embodiment of the application, 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 one embodiment of the application, the sharp corner transitions of the heat exchanger half-moon-shaped opening, the inlet section and the outlet section are all rounded to prevent stress concentration and reduce the flow resistance.

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

[0057] While the application has been described with reference to particular embodiments thereof, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present application. It will be apparent to those skilled in the art that numerous modifications can be made within the scope of the present application as defined by the appended claims. It is intended that all such modification fall within the spirit and scope of the present application. It will be understood that the features described in connection with one embodiment can be used in connection with another embodiment.

Claims

1. A high power-to-weight ratio fuel oil lubricant microchannel heat exchanger characterized by The application relates to a heat exchanger, which 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 from top to bottom in sequence, wherein 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 hot-side heat exchange plates (4) and the cold-side heat exchange plates (5) are alternately stacked in sequence along the vertical direction, the hot-side heat exchange plates (4) and the cold-side heat exchange plates (5) are provided with groove portions, and the groove portions form heat exchange channels for hot fluid and cold fluid; 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 (6) have the same structure; a circular opening is formed at each of a pair of top corners of the upper cover plate (2), a half-moon-shaped opening is formed at each of four top corners of the upper solid plate, a half-moon-shaped opening is formed at each of four top corners of the hot-side heat exchange plate (4), a half-moon-shaped opening is formed at each of four top corners of the cold-side heat exchange plate (5), a half-moon-shaped opening is formed at each of four top corners of the lower solid plate (6), and a circular opening is formed at each of a pair of top corners of the lower cover plate (7); the four half-moon-shaped openings of the upper solid plate (3), the four half-moon-shaped openings of the hot-side heat exchange plate (4), the four half-moon-shaped openings of the cold-side heat exchange plate (5) and the four half-moon-shaped openings of the lower solid plate (6) are correspondingly arranged and stacked to form four half-moon-shaped channels (11) in cross section, the four half-moon-shaped channels (11) in cross section are divided into two first half-moon-shaped channels (11A) at a first pair of opposite corners and two second half-moon-shaped channels (11B) at a second pair of opposite corners, the inlets and outlets (16) of the hot fluid heat exchange channels are communicated with the two first half-moon-shaped channels (11A) at the first pair of opposite corners, and the inlets and outlets (17) of the cold fluid heat exchange channels are communicated with the two second half-moon-shaped channels (11B) at the second pair of opposite corners; one end of each of the two upper cover plate joints (1) is connected to the circular openings at the first pair of opposite corners of the upper cover plate (2) and communicated with the corresponding two first half-moon-shaped channels (11A), and one end of each of the two lower cover plate joints (8) is connected to the circular openings at the second pair of opposite corners of the lower cover plate (7) and communicated with the corresponding two second half-moon-shaped channels (11B); the upper surface of each hot-side heat exchange plate (4) is provided with a plurality of hot-side micro-channels (4-2) arranged in parallel and forming a hot-side micro-channel group, the two ends of each hot-side micro-channel (4-2) are communicated with the two half-moon-shaped openings at one pair of opposite corners, and the hot-side micro-channel group on each hot-side heat exchange plate (4) forms a hot fluid heat exchange channel with the cold-side heat exchange plate (5) or the upper solid plate (3) above the hot-side heat exchange plate (4). ​ ​ ​ ​ ​ ​ ​ ​ The upper surface of each cold side heat exchange plate (5) is provided with a plurality of cold side microchannels (5-2) arranged in parallel to form a cold side microchannel group, the two ends of the cold side microchannel (5-2) are communicated with two crescent-shaped openings at the other pair of opposite corners respectively, and a cold fluid 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, 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 central symmetry; The hot side microchannels (4-2) or the cold side microchannels (5-2) are sine wave-shaped channels, 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 arranged at an angle of 135°, from the angle of the vertical hot side heat exchange plate (4) upper surface, the main heat exchange section of the hot side microchannel (4-2) and the main heat exchange section of the cold side microchannel (5-2) coincide, the inlet section of the hot side microchannel (4-2) and the outlet section of the cold side microchannel (5-2) are arranged at an angle of 90°, the outlet section of the hot side microchannel (4-2) and the inlet section of the cold side microchannel (5-2) are arranged at an angle of 90°, the outlet section of the hot side microchannel (4-2) and the inlet section of the cold side microchannel (5-2) coincide, and the outlet section of the cold side microchannel (5-2) and the inlet section of the hot side microchannel (4-2) coincide; the inlet section and the outlet section are sine wave-shaped channels, and the main heat exchange section is a sine wave-shaped channel.

2. A high duty ratio fuel oil lubricating oil microchannel heat exchanger according to claim 1, 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.

3. A high duty ratio fuel oil lubricating oil microchannel heat exchanger according to claim 1, characterized in that: The channel arrangement direction of the hot side microchannels (4-2) or the cold side microchannels (5-2) is perpendicular to the direction of fluid flow in the main heat exchange section, the upper surface of the hot side microchannels (4-2) or the cold side microchannels (5-2) is flat or has a certain arc, which is determined according to the 3D printing process.

4. A high duty ratio fuel oil lubricating 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 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) and the surface of the upper cover plate (2) are connected together by friction stir welding, and the lower surface of the lower solid plate (6) and the surface of the lower cover plate (7) are connected together by friction stir welding, in addition to friction stir welding, electron beam welding or vacuum diffusion welding can also be used to weld the upper and lower solid plates and the upper and lower cover plates.

5. A high duty ratio fuel oil lubricating oil microchannel heat exchanger according to claim 1, 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 half-moon openings of the upper and lower solid plates and the outer contours of the upper and lower solid plates, between the half-moon openings of the hot-side heat exchange plates (4) and the outer contours of the hot-side heat exchange plates, between the half-moon openings of the cold-side heat exchange plates (5) and the outer contours of the cold-side heat exchange plates, between the outermost recesses of the main heat exchange sections of the hot-side heat exchange plates (4) and the outer contours of the hot-side heat exchange plates, and between the outermost recesses of the main heat exchange sections of the cold-side heat exchange plates (5) and the outer contours of the cold-side heat exchange plates. The thickness of the partition walls depends on the working pressure of the hot and cold fluids.

6. A high duty ratio fuel oil lubricating oil microchannel heat exchanger according to claim 4, characterized in that: The material of the main body of the heat exchanger is an aluminum alloy or other metal with small density that can be used for 3D printing.

7. A high duty ratio fuel oil lubricating oil microchannel heat exchanger according to claim 1, characterized in that: The inlet sections, the main heat exchange sections and the outlet sections of the hot-side heat exchange plates and the cold-side heat exchange plates are all effective heat exchange areas.

Images