Environment-friendly heat exchanger for air conditioner

Abstract

The environment-friendly air conditioner heat exchanger comprises a heat exchange tube and fins, and the fins are arranged in the length direction of the heat exchange tube. The fins are provided with through holes and supporting wings, the heat exchange tubes penetrate through the through holes in the fins and are in interference fit with the through holes, the supporting wings are arranged on the front faces of the fins, and the supporting wing of the rear fin abuts against the back face of the front supporting wing. The inner diameter of each heat exchange pipe is 3-4 mm, the multiple heat exchange pipes are parallel to one another, a refrigerant flow path is formed after the heat exchange pipes are communicated, the volume of the refrigerant flow path serves as the refrigerant filling volume, and the ratio of the refrigerant filling volume to the number of the fins is 2-3 L / piece.

Description

Technical Field

[0001] The present invention relates to a heat exchanger for air conditioners, in particular to a finned tube heat exchanger for high-efficiency and environment-friendly air conditioners. Background Art

[0003] The heat exchanger is an important component of equipment such as refrigerators and air conditioners, and is the most important factor affecting the overall energy efficiency and overall volume of the product. At present, the mainstream of finned tube heat exchangers for air conditioners at home and abroad is a pipe diameter of φ7mm. There are also experts and enterprises that have developed finned tube heat exchangers with a φ5mm pipe diameter and have carried out trial production. Taking the φ5mm heat exchanger as an example, the weight of the heat exchanger of a single air conditioner is 3.5KG. Calculated based on the air conditioner production from January to November 2021, the copper consumption of the φ5mm heat exchanger is 69,104 tons. Since March 2020, the copper price has been showing a fluctuating upward trend, reaching a maximum of 9,614.5 US dollars / ton, setting a new high in the past 10 years, and currently basically remaining at a high level of around 9,000 US dollars / ton. Therefore, designing a heat exchanger with lower cost and better heat transfer is an important issue faced by the current refrigeration industry. Summary of the Invention

[0004] The finned tube heat exchanger includes heat exchange tubes and fins, and the fins are arranged along the length direction of the heat exchange tubes; there are through holes and support wings on the fins, the heat exchange tubes pass through the through holes on the fins and are in interference fit with the through holes, the support wings are arranged on the front surface of the fins, and the support wing of the latter fin abuts against the back surface of the previous support wing. The finned tube heat exchanger uses cross-flow heat exchange between cold / hot fluids through a partition wall. The refrigerant flows inside the tubes, and the air is outside the tubes. The heat transfer inside the tubes is mainly based on phase change heat transfer, and the heat transfer outside the tubes is convective heat transfer.

[0005] The purpose of the present invention is to provide a small-diameter finned tube heat exchanger that saves the refrigerant filling amount while maintaining the heat transfer performance without reduction.

[0006] The environment-friendly air conditioner heat exchanger includes heat exchange tubes and fins, and the fins are arranged along the length direction of the heat exchange tubes; there are through holes and support wings on the fins, the heat exchange tubes pass through the through holes on the fins and are in interference fit with the through holes, the support wings are arranged on the front surface of the fins, and the support wing of the latter fin abuts against the back surface of the previous support wing; the inner diameter of the heat exchange tubes is 3mm to 4mm, there are multiple heat exchange tubes, the heat exchange tubes are parallel to each other, and after being connected, they form a refrigerant flow path. The volume of the refrigerant flow path is used as the refrigerant filling volume, and the ratio of the refrigerant filling volume to the number of fins is 2 to 3L / fin. The reduction of the pipe diameter of the heat exchange tubes and the configuration of the heat exchange tubes and fins enable the heat exchanger to save 21% of the refrigerant filling amount while maintaining the same heat transfer efficiency as the existing air conditioner heat exchanger under the same power. The refrigerant saved by a single heat exchanger is at least about 100g.

[0007] Furthermore, each through-hole of the fin penetrates through the heat exchange tube. The area of the fin except for the through-holes is defined as the effective heat exchange area, and the ratio of the effective heat exchange area to the total area of the fin is 0.957 - 0.973. The refrigerant undergoes a phase change inside the heat exchange tube to achieve heat transfer. The fins greatly increase the heat transfer area and reduce the convective heat transfer resistance on both sides. The heat transfer effect at the through-holes penetrated by the heat exchange tube can be basically ignored, and the area of the fin except for the through-holes is used as the effective heat exchange area. By setting the effective heat exchange area, the heat exchange efficiency is improved.

[0008] Furthermore, the heat exchanger includes multiple heat exchange tubes. Each heat exchange tube includes two straight tube segments arranged in parallel and a bent tube segment located between the straight tube segments. The bent tube segments of all the heat exchange tubes are on the same side of the heat exchanger. The straight tube segments of the heat exchange tubes penetrate through the through-holes of the fins, and there are gaps between adjacent fins. The fins sleeved on the heat exchange tubes form a fin assembly. In this way, the heat exchanger has a high ability to prevent ash accumulation and blockage. The air flows horizontally outside the tubes for heat exchange, and the disturbance of the air is enhanced, effectively preventing blockage.

[0009] Furthermore, the fins are formed by punching holes in a metal substrate, and the ratio of the wall thickness of the heat exchange tube to the thickness of the metal substrate is 2.1 - 4.5. Preferably, the ratio of the wall thickness of the heat exchange tube to the thickness of the metal substrate is 3. In this way, when the heat exchange tube is expanded, the gap between the heat exchange tube and the fin can be well changed from clearance fit to interference fit, making the connection between the heat exchange tube and the fin reliable.

[0010] Furthermore, the hole wall of the through-hole of the fin has an extended section extending outward. The extended section is cylindrical, and the other end of the extended section has a flared trumpet mouth. The ratio of the height of the extended section to the width of the trumpet mouth is 10 - 16. Preferably, the ratio of the height of the extended section to the width of the trumpet mouth is 13.

[0011] In this way, the trumpet mouth can resist the previous (or next) fin during tube expansion, preventing the extended section of the current fin from inserting into the through-hole of the previous (or next) fin. At the same time, the extended section and the trumpet mouth maintain the gap between adjacent fins, thus meeting the requirement of the ratio of the cumulative gap width between the fins to the total width of the fin assembly, improving the heat exchange performance and anti-blocking performance of the heat exchanger. Taking the direction from the first fin to the last fin as the width direction of the heat exchanger, after the single fins form a fin assembly, the fins are perpendicular to the width direction of the heat exchanger.

[0012] Furthermore, the straight tube segments of all the heat exchange tubes are parallel to each other, the center lines of the heat exchange tubes in the same row are in the same plane, and there is at least one row of heat exchange tubes.

[0013] Further, the bent pipe section is exposed outside the fin assembly, and both ends of the straight pipe section are also exposed outside the fin assembly. Preferably, the ratio of the exposed width of the bent pipe section to the exposed width of the straight pipe section is 0.9 - 1.1. Most preferably, the ratio of the exposed width of the bent pipe section to the exposed width of the straight pipe section is 1. Further, all the heat exchange tubes respectively pass through the corresponding through holes on the fins, and the fins are in interference fit with the heat exchange tubes. A plurality of heat exchange tubes arranged in parallel and with their central axes in the same plane are taken as a group, and the heat exchanger has at least one group of heat exchange tubes; the heat exchange tubes in the same group are arranged at equal intervals along the length of the fins. For a single-cooling machine, one group of heat exchange tubes can complete the work. For a heating and cooling machine, two or more groups of heat exchange tubes may be required.

[0014] Further, the heat exchanger has two straight plate parts and a transition part connecting the two straight plate parts, and the transition part is arc-shaped.

[0015] The advantages of the present invention are as follows: Based on the change in the size (inner diameter or outer diameter) of the heat exchange tubes, compared with the original Haier 5mm machine test, at the same power, the COP coefficient is increased by 0.15, the volume is reduced by 10%, the weight is reduced by 25%, and the refrigerant charge is reduced by 21%. Description of the Drawings

[0016] Figure 1 is a schematic diagram of the present invention.

[0017] Figure 2 is a perspective view of the present invention. Detailed Embodiments

[0018] Next, the technical solutions of the present invention will be described clearly and completely in conjunction with the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0019] In some embodiments, the environmentally friendly air conditioner heat exchanger includes a heat exchange tube 1 and fins 2, and the fins 2 are arranged along the length direction of the heat exchange tube 1; there are through holes and support wings on the fins 2, the heat exchange tube 1 passes through the through holes on the fins 2 and is in interference fit with the through holes, the support wings are arranged on the front surface of the fins 2, and the support wing of the latter fin 2 abuts against the back surface of the support wing of the previous one; the inner diameter of the heat exchange tube 1 is 3mm - 4mm, there are multiple heat exchange tubes 1, the heat exchange tubes 1 are parallel to each other, and after being connected, they form a refrigerant flow path. The volume of the refrigerant flow path is used as the refrigerant charge volume, and the ratio of the refrigerant charge volume to the number of fins 2 is 2 - 3L / fin. The reduced diameter of the heat exchange tubes 1 of this heat exchanger and the configuration of the heat exchange tubes 1 and the fins 2 enable the heat exchanger to save 21% of the refrigerant charge without reducing the heat exchange efficiency compared with the existing air conditioner heat exchanger under the same power. The refrigerant saved by a single heat exchanger is at least about 100g.

[0020] In some embodiments, each through-hole of the fin 2 passes through the heat exchange tube 1. The area of the fin 2 except for the through-holes is taken as the effective heat exchange area. The ratio of the effective heat exchange area to the total area of the fin 2 is 0.957 - 0.973. The refrigerant undergoes a phase change in the heat exchange tube 1 to achieve heat transfer. The arrangement of the fins 2 greatly increases the heat transfer area and reduces the convective heat transfer resistance on both sides. The heat exchange effect at the through-holes through which the heat exchange tube 1 passes can be basically ignored, and the area of the fin 2 except for the through-holes is taken as the effective heat exchange area. By setting the effective heat exchange area, the heat exchange efficiency is improved.

[0021] In some embodiments, an environment-friendly air-conditioning heat exchanger includes a heat exchange tube 1 and fins 2. The fins 2 are arranged along the length direction of the heat exchange tube 1; there are through-holes and support wings on the fins 2. The heat exchange tube 1 passes through the through-holes on the fins 2 and is in interference fit with the through-holes. The support wings are arranged on the front surface of the fins 2, and the support wing of the latter fin 2 abuts against the back surface of the support wing of the previous one; the outer diameter of the heat exchange tube 1 is 3.8 mm - 4.3 mm. There are multiple heat exchange tubes 1, and the heat exchange tubes 1 are parallel to each other. After being connected, the heat exchange tubes 1 form a refrigerant flow path, and the refrigerant fills the refrigerant flow path. The weight ratio of the heat exchange tube 1 to the refrigerant is 1.48 - 2.75. The diameter of the heat exchange tube 1 of this heat exchanger is reduced, and the configuration of the heat exchange tube 1 and the fins 2 enables the heat exchanger to save more than 25.6% of the material used compared with the existing air-conditioning heat exchanger (the diameter of the heat exchange tube 1 is 5 mm) under the same power, and at the same time, the heat exchange energy efficiency ratio is increased by 0.15 - 0.42.

[0022] In some embodiments, the weight ratio of the heat exchange tube 1 to the refrigerant is 2.1 - 2.15. The heat exchange tube 1 is made of a copper tube or a copper alloy tube, and the minimum copper consumption saved by a single heat exchanger is about 787 g.

[0023] In some embodiments, each through-hole of the fin 2 passes through the heat exchange tube 1. The heat exchanger includes multiple heat exchange tubes 1. Each heat exchange tube 1 includes two straight pipe segments arranged in parallel and a bent pipe segment located between the straight pipe segments. The bent pipe segments of all the heat exchange tubes 1 are on the same side of the heat exchanger. The straight pipe segments of the heat exchange tube 1 penetrate through the through-holes of the fins 2. There is a gap between adjacent fins 2, and the fins 2 sleeved on the heat exchange tube 1 form a fin 2 assembly; the weight ratio of the heat exchange tube 1 to the fin 2 assembly is 0.56 - 1.03. The diameter of the heat exchange tube 1 of this heat exchanger is reduced, and the configuration of the heat exchange tube 1 and the fins 2 enables the heat exchanger to save about 42% of the material used for the fins 2 compared with the existing air-conditioning heat exchanger (the diameter of the heat exchange tube 1 is 5 mm) under the same power.

[0024] In some embodiments, the weight ratio of the heat exchange tube 1 to the fin 2 assembly is 0.79 - 0.8. The fins 2 are made of aluminum fins 2, and the minimum aluminum consumption saved by a single heat exchanger is about 750 g.

[0025] In some embodiments, each fin 2 has three dimensions: length, width and height. Among these three dimensions, the smallest dimension is used as thickness, the largest dimension is used as length, and the remaining third dimension is used as width. The projected area of ​​the fin 2 is calculated by multiplying the length by the width. The ratio of the sum of the projected areas of all fins 2 in the fin 2 assembly to the weight of the refrigerant is: 0.065~0.071kg / m 3 Compared with the existing heat exchanger, the heat exchange efficiency ratio of this heat exchanger is improved by 0.15~0.42, and the heat exchanger capacity is increased by about 255w.

[0026] In some embodiments, the heat exchanger includes a plurality of heat exchange tubes 1, each heat exchange tube 1 includes two parallel straight tube sections and a curved tube section between the straight tube sections, the curved tube sections of all heat exchange tubes 1 are located on the same side of the heat exchanger, the straight tube sections of the heat exchange tubes 1 pass through the through holes of the fins 2, there are gaps between adjacent fins 2, and the fins 2 passing through the heat exchange tubes 1 form a fin 2 assembly. In this way, the heat exchanger has a higher ability to prevent dust accumulation and blockage, the air flows horizontally outside the tube for heat exchange, the turbulence of the air is enhanced, and blockage can be effectively prevented.

[0027] In some embodiments, the fins 2 are punched on a metal substrate, and the ratio of the wall thickness of the heat exchange tube 1 to the thickness of the metal substrate is 2.1 to 4.5. Preferably, the ratio of the wall thickness of the heat exchange tube 1 to the thickness of the metal substrate is 3. In this way, when the heat exchange tube 1 is expanded, the heat exchange tube 1 and the fins 2 can be well changed from a clearance fit to an interference fit, so that the connection between the heat exchange tube 1 and the fins 2 is reliable.

[0028] In some embodiments, the hole wall of the through hole of the fin 2 has an extension section extending outward, the extension section is cylindrical, the other end of the extension section has an outwardly expanded bell mouth, and the ratio of the height of the extension section to the width of the bell mouth is 10 to 16. Preferably, the ratio of the height of the extension section to the width of the bell mouth is 13.

[0029] In this way, the bell mouth can resist the previous (or next) fin 2 during tube expansion, so that the extension section of the current fin 2 does not insert into the through hole of the previous (or next) fin 2. At the same time, the setting of the extension section and the bell mouth maintains the gap between two adjacent fins 2, thereby meeting the requirement of the ratio of the cumulative gap width between the fins 2 to the total width of the fin 2 assembly, and improving the heat exchange performance and anti-clogging performance of the heat exchanger. The direction from the first fin 2 to the last fin 2 is the width direction of the heat exchanger. After the single fin 2 forms the fin 2 assembly, the fin 2 is perpendicular to the width direction of the heat exchanger.

[0030] In some embodiments, the straight tube sections of all heat exchange tubes 1 are parallel to each other, the center lines of the heat exchange tubes 1 in the same row are located on the same plane, and there is at least one row of heat exchange tubes 1 .

[0031] In some embodiments, the bent pipe section is exposed outside the fin 2 assembly, and both ends of the straight pipe section are also exposed outside the fin 2 assembly. Preferably, the ratio of the exposed width of the bent pipe section to the exposed width of the straight pipe section is 0.9 to 1.1. Most preferably, the ratio of the exposed width of the bent pipe section to the exposed width of the straight pipe section is 1.

[0032] In some embodiments, all the heat exchange tubes 1 respectively pass through the corresponding through holes on the fins 2, and the fins 2 are in interference fit with the heat exchange tubes 1. A plurality of heat exchange tubes 1 arranged in parallel and with their central axes in the same plane are taken as a group, and the heat exchanger has at least one group of heat exchange tubes 1; the heat exchange tubes 1 in the same group are arranged at equal intervals along the length of the fins 2. For a single-cooling machine, one group of heat exchange tubes 1 can complete the work. For a heating and cooling machine, two or more groups of heat exchange tubes 1 may be required.

[0033] In some embodiments, the heat exchanger has two straight plate portions and a transition portion connecting the two straight plate portions, and the transition portion is arc-shaped.

[0034] The content described in the embodiments of this specification is only an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms stated in the embodiments, and the protection scope of the present invention also extends to equivalent technical means that those skilled in the art can think of according to the inventive concept of the present invention.

Claims

1. An environmentally friendly air conditioning heat exchanger, comprising a heat exchange tube and a fin, wherein the fin is arranged along the length direction of the heat exchange tube; the fin is provided with a through hole and a supporting wing, the heat exchange tube passes through the through hole on the fin and is interference fit with the through hole, the supporting wing is arranged on the front side of the fin, and the supporting wing of the rear fin abuts against the back side of the supporting wing of the front fin; the characteristics are: The inner diameter of the heat exchange tube is 3mm~4mm. There are multiple heat exchange tubes, which are parallel to each other. The heat exchange tubes are connected to form a refrigerant flow path. The volume of the refrigerant flow path is used as the refrigerant filling volume. The ratio of the refrigerant filling volume to the number of fins is 2~3L / fin.

2. The environmentally friendly air conditioning heat exchanger according to claim 1, characterized in that: Each through hole of the fin passes through the heat exchange tube, and the area of ​​the fin excluding the through hole is the effective heat exchange area. The ratio of the effective heat exchange area to the total area of ​​the fin is 0.957~0.

973.

3. The environmentally friendly air conditioning heat exchanger according to claim 2, characterized in that: The heat exchanger includes a plurality of heat exchange tubes, each of which includes two straight tube sections arranged in parallel and a curved tube section located between the straight tube sections. The curved tube sections of all heat exchange tubes are located on the same side of the heat exchanger. The straight tube sections of the heat exchange tubes pass through the through holes of the fins. There are gaps between adjacent fins. The fins passing through the heat exchange tubes form a fin assembly.

4. The environmentally friendly air conditioning heat exchanger according to any one of claims 1 to 3, characterized in that: The fins are punched on a metal substrate, and the ratio of the wall thickness of the heat exchange tube to the thickness of the metal substrate is 2.1~4.

5.

5. The environmentally friendly air conditioning heat exchanger according to claim 4, characterized in that: The ratio of the wall thickness of the heat exchange tube to the thickness of the metal substrate is 3.

6. The environmentally friendly air conditioning heat exchanger according to any one of claims 1 to 3, characterized in that: The hole wall of the through hole of the fin has an extension section extending outward, the extension section is cylindrical, the other end of the extension section has an outwardly expanded bell mouth, and the ratio of the height of the extension section to the width of the bell mouth is 10-16.

7. The environmentally friendly air conditioning heat exchanger according to claim 6, characterized in that: The ratio of the height of the extension section to the width of the bell mouth is 13.

8. The environmentally friendly air conditioning heat exchanger according to claim 6, characterized in that: The straight tube sections of all heat exchange tubes are parallel to each other, the center lines of the heat exchange tubes in the same row are located on the same plane, and there is at least one row of heat exchange tubes.

9. The environmentally friendly air conditioning heat exchanger according to any one of claims 1 to 3, characterized in that: The curved pipe section is exposed outside the fin assembly, and two ends of the straight pipe section are also exposed outside the fin assembly.

10. The environmentally friendly air conditioning heat exchanger according to claim 9, characterized in that: The ratio of the exposed width of the curved pipe section to the exposed width of the straight pipe section is 0.9~1.

1.

11. The environmentally friendly air conditioning heat exchanger according to claim 10, characterized in that: The ratio of the exposed width of the curved pipe section to the exposed width of the straight pipe section is 1.

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