Method for determining tube diameter of heat exchanger, heat exchanger and air conditioner

Abstract

The application relates to the technical field of air conditioners, and discloses a method for determining the pipe diameter of a heat exchanger. The method comprises the following steps: when the refrigerant viscosity of a refrigeration system is less than or equal to a first viscosity value, a first coefficient a is obtained according to the target capacity E of the refrigeration system and the unit capacity e of the refrigeration system; a first parameter b is obtained according to the ratio of the refrigerant charging amount m of the refrigeration system and the first coefficient a; and the pipe diameter of the heat exchanger is determined according to the size of the first parameter b. The method is used for determining the pipe diameter of the heat exchanger matched with flammable refrigerants such as R290 or R161, so that the refrigerant in the heat exchanger can be timely heat-exchanged, the flow rate of the refrigerant in the heat exchanger is improved, and the heat exchange efficiency of the heat exchanger is improved. The application further discloses a heat exchanger and an air conditioner.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of air conditioners, and for example to a method for determining a pipe diameter of a heat exchanger, a heat exchanger, and an air conditioner. BACKGROUND

[0002] There are various types of refrigerants for air conditioners, including R32, R22, R410a, R290, or R161, etc. Compared with conventional refrigerants such as R32, R22, or R410a, refrigerants such as R290 or R161 are more flammable. For safety considerations, the maximum allowable charge of flammable refrigerants in an air conditioning system is only half of that of conventional refrigerants, or even less.

[0003] In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related art:

[0004] In the case where the pipe diameter of the heat exchange pipe of the heat exchanger is large and the charge of the refrigerant is small, it is usually necessary to increase the displacement of the compressor to increase the circulation amount of the refrigerant, and thus to improve the heat exchange capacity of the air conditioning system. However, for a heat exchanger with a large pipe diameter, the refrigerant at the pipe wall of the heat exchange pipe exchanges heat, while the heat exchange efficiency of the refrigerant at the center of the heat exchange pipe is very low, and the pipe diameter of the heat exchange pipe is large, the flow rate of the refrigerant in the heat exchange pipe is reduced, and in the case where the amount of refrigerant is small, the situation of early overheating or subcooling is likely to occur, resulting in waste of the effective heat exchange capacity of the rear part of the heat exchanger.

[0005] It should be noted that the information disclosed in the above BACKGROUND section is only used to strengthen the understanding of the background of the present application, and therefore can include information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0006] To provide a basic understanding of some aspects of the disclosed embodiments, the following brief summary is given. The summary is not an extensive overview of the application, nor is it intended to identify key / critical elements of the application or to delineate the scope of the embodiments. The sole purpose of the summary is to present some concepts of the embodiments in a simplified form as a prelude to the more detailed description that is presented later.

[0007] The embodiments of the present disclosure provide a method for determining a pipe diameter of a heat exchanger, a heat exchanger, and an air conditioner. The method determines the pipe diameter of the heat exchanger that matches the charge of flammable refrigerants such as R290 or R161, so that the refrigerant in the heat exchanger exchanges heat in time, improves the flow rate of the refrigerant in the heat exchanger, and thus improves the heat exchange efficiency of the heat exchanger.

[0008] In some embodiments, the method for determining the tube diameter of the heat exchanger comprises: obtaining a first coefficient a according to a target capacity E of the refrigeration system and a unit capacity e of the refrigeration system when the refrigerant viscosity of the refrigeration system is less than or equal to a first viscosity value; obtaining a first parameter b according to a ratio of a refrigerant charge m of the refrigeration system and the first coefficient a; and determining the tube diameter of the heat exchanger according to the size of the first parameter b.

[0009] Optionally, obtaining the first coefficient a according to the target capacity E of the refrigeration system and the unit capacity e of the refrigeration system comprises: when the target capacity E of the refrigeration system is less than or equal to a first preset capacity, a = E / e*f1; and when the target capacity E of the refrigeration system is greater than the first preset capacity, a = E / e*f2. Wherein, f1 and f2 are constants, and f1 is less than f2.

[0010] Optionally, f1 is greater than or equal to 380 and less than or equal to 420. And / or, f2 is greater than or equal to 580 and less than or equal to 620.

[0011] Optionally, determining the tube diameter of the heat exchanger according to the size of the first parameter b comprises: when the first parameter b is greater than 0.6 and less than or equal to 0.9, the tube diameter of the heat exchanger is a first tube diameter value; and when the first parameter b is less than 0.6, the tube diameter of the heat exchanger is a second tube diameter value. Wherein, the first tube diameter value is greater than the second tube diameter value. When the first parameter b is greater than 0.5 and less than or equal to 0.9, the tube diameter of the heat exchanger is a third tube diameter value; and when the first parameter b is less than 0.5, the tube diameter of the heat exchanger is a fourth tube diameter value. Wherein, the third tube diameter value is greater than the fourth tube diameter value.

[0012] Optionally, the first tube diameter value is greater than 5mm and less than or equal to 6mm. The second tube diameter value is greater than 4mm and less than or equal to 5mm. And / or, the third tube diameter value is greater than 6mm and less than or equal to 7mm, and the fourth tube diameter value is greater than 5mm and less than or equal to 6mm.

[0013] Optionally, the first viscosity value comprises 145-150μPa·s.

[0014] Optionally, the method for determining the tube diameter of the heat exchanger further comprises: obtaining a branch quantity threshold value y of the heat exchanger according to the tube diameter r of the heat exchanger, the length s of the heat exchange tube and the number x of the heat exchange tube; and obtaining a reasonable branch quantity Y of the heat exchanger according to the branch quantity threshold value y. Wherein, Y is greater than or equal to y.

[0015] Optionally, y = r 2 *s*x / q / b. Wherein, q is a constant.

[0016] In some embodiments, the heat exchanger is obtained by the aforementioned method for determining the tube diameter of the heat exchanger.

[0017] In some embodiments, the air conditioner comprises a compressor, a four-way valve, an outdoor heat exchanger, a throttling element and an indoor heat exchanger connected in sequence and forming a refrigerant circulation system. The outdoor heat exchanger and / or the indoor heat exchanger is the heat exchanger described above.

[0018] The method for determining the pipe diameter of the heat exchanger, the heat exchanger and the air conditioner provided by the embodiments of the present disclosure can achieve the following technical effects:

[0019] The refrigerant with large viscosity is not suitable for the heat exchanger with small pipe diameter. When the viscosity of the refrigerant is less than or equal to the first viscosity value, the subsequent selection is performed. By combining the target capacity of the refrigeration system and the unit capacity of the refrigeration system, a dimensionless parameter of the heat exchange capacity of the heat exchanger is obtained. Then, by combining the refrigerant charge of the refrigeration system and the dimensionless parameter of the heat exchange capacity of the heat exchanger, the refrigerant amount per unit heat exchange pipe is obtained. Finally, the pipe diameter of the heat exchange pipe is determined by the refrigerant amount per unit heat exchange pipe. Through the method provided by the embodiments of the present disclosure, the heat exchange pipe with small pipe diameter can be selected when the refrigerant charge is small, so that the refrigerant in the heat exchanger can be exchanged in time, thereby improving the flow rate of the refrigerant in the heat exchanger and improving the heat exchange efficiency of the heat exchanger.

[0020] The foregoing general description and the following description are only exemplary and explanatory, and are not used to limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0021] One or more embodiments are exemplarily illustrated by corresponding drawings, which do not constitute limitation on the embodiments, elements with the same reference numerals in the drawings are shown as similar elements, the drawings do not constitute proportional limitation, and wherein:

[0022] Figure 1 is a structure schematic diagram of the heat exchanger provided by the embodiments of the present disclosure;

[0023] Figure 2 is a refrigerant flow path schematic diagram of the heat exchanger as an outdoor heat exchanger under refrigeration operation;

[0024] Figure 3 is a refrigerant flow path schematic diagram of the heat exchanger as an outdoor heat exchanger under heating operation;

[0025] Figure 4 is a flow schematic diagram of the method for determining the pipe diameter of the heat exchanger provided by the embodiments of the present disclosure;

[0026] Figure 5 is a flow schematic diagram of the method for determining the pipe diameter of the heat exchanger provided by the embodiments of the present disclosure, which determines the pipe diameter of the heat exchanger according to the first parameter b.

[0027] Reference signs:

[0028] 100: heat exchanger body; 101: first heat exchange part; 1011: first heat exchange branch; 1012: second heat exchange branch; 102: second heat exchange part;

[0029] 201: first branch pipe; 202: second branch pipe; 203: main pipe; 204: branch shell; 301: first branch element; 302: second branch element. DETAILED DESCRIPTION

[0030] In order to enable persons skilled in the art to more fully understand the features and technical contents of the embodiments of the present disclosure, the implementation of the embodiments of the present disclosure is described in detail below with reference to the accompanying drawings, which are only used for reference and do not limit the embodiments of the present disclosure. In the following technical description, in order to facilitate explanation, a plurality of details are provided to provide a full understanding of the disclosed embodiments. However, one or more embodiments can still be implemented without these details. In other cases, well-known structures and devices can be simplified to facilitate the drawings.

[0031] The terms "first", "second", and the like in the specification and claims of the embodiments of the present disclosure and the above drawings are used to distinguish similar objects, and do not necessarily have to describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present disclosure described herein can be implemented. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion.

[0032] Unless otherwise specified, the term "a plurality of" means two or more.

[0033] In the embodiments of the present disclosure, the character " / " represents an "or" relationship between the objects before and after it. For example, A / B means: A or B.

[0034] The term "and / or" is a description of the association relationship between objects, which means that there can be three relationships. For example, A and / or B means: A or B, or, A and B, the three relationships.

[0035] The term "corresponding" can refer to an association relationship or a binding relationship. A and B correspond to each other means that A and B have an association relationship or a binding relationship.

[0036] It should be noted that the embodiments in the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0037] The embodiments of the present disclosure provide a heat exchanger.

[0038] The heat exchanger provided by the embodiments of the present disclosure is used in an air conditioner with a refrigerant charge less than or equal to a preset charge. The heat exchanger comprises a heat exchange body 100 and a distribution element. The heat exchange body 100 comprises a first heat exchange branch 1011 and a second heat exchange branch 1012 arranged in parallel, and the pipe diameters of the heat exchange pipes of the first heat exchange branch 1011 and the second heat exchange branch 1012 are less than or equal to a first preset pipe diameter value. The distribution element comprises a first distribution branch pipe 201 and a second distribution branch pipe 202, the first distribution branch pipe 201 is connected to the heat exchange pipes of the first heat exchange branch 1011, and the second distribution branch pipe 202 is connected to the heat exchange pipes of the second heat exchange branch 1012. The pipe diameters of the first distribution branch pipe 201 and the second distribution branch pipe 202 are less than or equal to a second preset pipe diameter value, and the first preset pipe diameter value is less than or equal to the second preset pipe diameter value.

[0039] For flammable refrigerants such as R293 or R161, the charge in the air conditioner is less. In the case of less refrigerant charge, the diameter of the heat exchange pipe of the existing heat exchanger is generally 7-10 mm, for example, 7 mm, 8 mm, 9 mm or 9.52 mm, etc. However, the charge of flammable refrigerants such as R293 or R161 in the air conditioner is only half or even less than that of commonly used refrigerants. In the case of larger pipe diameter of the heat exchange pipe of the heat exchanger and less refrigerant charge, it is generally necessary to increase the displacement of the compressor to increase the circulation amount of the refrigerant, thereby improving the heat exchange capacity of the air conditioning system. However, for the heat exchanger with a larger pipe diameter, the refrigerant at the pipe wall of the heat exchange pipe exchanges heat, and the heat exchange efficiency of the refrigerant at the center of the heat exchange pipe is very low. Moreover, the pipe diameter of the heat exchange pipe is large, and the flow rate of the refrigerant in the heat exchange pipe is reduced. In the case of small amount of refrigerant, the refrigerant is easily overheated or supercooled, resulting in waste of the heat exchange capacity of the rear part of the heat exchanger.

[0040] Therefore, the embodiments of the present disclosure provide a heat exchanger with heat exchange pipes of the first heat exchange branch 1011 and the second heat exchange branch 1012 having a pipe diameter less than or equal to a first preset pipe diameter value, i.e., a heat exchanger with small pipe diameter, which can enable the less charged refrigerant to be fully and timely exchanged in the heat exchange pipe, thereby improving the flow rate of the refrigerant in the heat exchanger and the heat exchange efficiency of the heat exchanger. Meanwhile, the heat exchanger provided by the embodiments of the present disclosure further comprises a distribution element, which comprises a first distribution branch pipe 201 connected to the heat exchange pipes of the first heat exchange branch 1011 and a second distribution branch pipe 202 connected to the heat exchange pipes of the second heat exchange branch 1012. The pipe diameters of the first distribution branch pipe 201 and the second distribution branch pipe 202 are less than or equal to a second preset pipe diameter value. It can be seen that the embodiments of the present disclosure simultaneously provide a distribution element with small pipe diameter matched with the heat exchange pipe with small pipe diameter, thereby improving the uniformity of the distribution element.

[0041] Optionally, the heat exchanger is used in an air conditioner with a refrigerant charge less than or equal to a preset charge, and the preset charge is 500-1200g. The greater the refrigerating capacity of the air conditioner, the more refrigerant is needed to charge in the air conditioner. For example, the refrigerant required for a unit refrigerating capacity is 500g, and it can also be understood that the refrigerant filled in a 1P air conditioner can be 500g, and the refrigerant filled in a 1.5P air conditioner can be 750-800g.

[0042] Optionally, the first preset pipe diameter value is less than or equal to 6mm; and / or, the second preset pipe diameter value is less than or equal to 7mm. Optionally, the pipe diameter of the heat exchange pipes of the first heat exchange branch 1011 and the second heat exchange branch 1012 is greater than or equal to 5mm and less than or equal to 6mm. The pipe diameter of the first liquid distribution branch pipe 201 and the second liquid distribution branch pipe 202 is greater than or equal to 5mm and less than or equal to 7mm.

[0043] Optionally, the pipe diameter of the heat exchange pipes of the first heat exchange branch pipe and the second heat exchange branch pipe can be 5mm-6mm, and the pipe diameter of the first liquid distribution branch pipe 201 and the second liquid distribution branch pipe 202 can be 5mm-7mm. For example, the pipe diameter of the heat exchange pipes of the first heat exchange branch 1011 and the second heat exchange branch 1012 is 5mm, and the pipe diameter of the first liquid distribution branch pipe 201 and the second liquid distribution branch pipe 202 is 5mm or 6mm; or, the pipe diameter of the heat exchange pipes of the first heat exchange branch 1011 and the second heat exchange branch 1012 is 6mm, and the pipe diameter of the first liquid distribution branch pipe 201 and the second liquid distribution branch pipe 202 is 6mm or 7mm.

[0044] Compared with the existing heat exchanger with a pipe diameter of 7-9mm, the pipe diameter of the heat exchange pipes and the liquid distribution branch pipes of the liquid distribution element in the heat exchanger provided by the embodiment of the present disclosure are smaller, and are more suitable for air conditioners filled with flammable refrigerants such as R293 or R161 and with a small charge.

[0045] Optionally, the heat exchange body 100 includes M heat exchange branches arranged in parallel, and the liquid distribution element includes liquid distribution branch pipes respectively connected to the M heat exchange branches, wherein M is a positive integer and M is greater than or equal to 3.

[0046] The heat exchange body 100 can include 3 or more heat exchange branches arranged in parallel, and the liquid distribution element includes 3 or more liquid distribution branch pipes respectively connected to the heat exchange branches one by one, and each liquid distribution branch pipe corresponds to a heat exchange branch. In the heat exchanger provided by the embodiment of the present disclosure, the pipe diameter of the heat exchange pipes is small, and accordingly, the heat exchange branch needs to be more when designing the pipe of the heat exchange pipe to improve the heat exchange efficiency of the heat exchanger.

[0047] Optionally, the liquid distribution element also includes a main pipe 203 and a liquid distribution shell 204 disposed between the main pipe 203 and the liquid distribution branch pipe, wherein the volume of the liquid distribution cavity formed inside the liquid distribution shell 204 is less than or equal to a preset volume value.

[0048] In the heat exchanger provided in this embodiment, the number of liquid distribution branches of the liquid distribution element is relatively large. To improve the uniformity of liquid distribution, the volume of the liquid distribution chamber within the liquid distribution element should not be too large. Optionally, the volume of the liquid distribution chamber is less than or equal to 5 cm³. 3 For example, the volume of the separating chamber can be 5 cm³. 3 4.8cm 3 4.6cm 3 4.4cm 3 4.2cm 3 wait.

[0049] Optionally, the liquid-dispensing element provided in this embodiment is a copper liquid distributor. The existing copper liquid-dispensing chamber, which has a relatively large volume, is improved by reducing its volume. Furthermore, a fine sieve can be placed inside the liquid-dispensing chamber of the copper liquid distributor to increase the turbulence of the refrigerant within the chamber, allowing for thorough dispersion and mixing of the gas and liquid phases of the refrigerant, thus improving the uniformity of liquid distribution. Optionally, the copper liquid distributor can be cylindrical or conical in shape.

[0050] Combination Figures 1-3 As shown, the heat exchanger body 100 includes a first heat exchange section 101 and a second heat exchange section 102, wherein the first heat exchange section 101 includes three heat exchange branches arranged in parallel. A first liquid distribution element 301 and a second liquid distribution element 302 are respectively provided at both ends of the first heat exchange section 101, and the liquid distribution branch pipes of the liquid distribution elements are connected to the heat exchange pipes of the heat exchange branches. Under refrigeration operation, the heat exchanger acts as the refrigerant flow path of the outdoor heat exchanger as follows... Figure 2 As shown. The refrigerant enters the first distribution element 301 from the main pipe 203, and is then distributed through various distribution branches into the heat exchange branches of the first heat exchange section 101. It then enters the second distribution element 302 for convergence, and then enters the second heat exchange section 102, finally exiting the heat exchanger. The second heat exchange section 102 extends the refrigerant flow path, resulting in more thorough heat exchange. During heating operation, the refrigerant flow path of the heat exchanger, acting as the outdoor heat exchanger, is as follows: Figure 3 As shown, the refrigerant flows through the second heat exchange section 102 and then enters the second liquid distribution element 302, where it is divided and flows into the various heat exchange branches of the first heat exchange section 101. Afterward, it enters the first liquid distribution element 301 for convergence and finally flows out of the heat exchanger. The heat exchange tubes of the first liquid distribution element 301, the second liquid distribution element 302, the first heat exchange section 101, and the second heat exchange section 102 all adopt the aforementioned small-diameter configuration. The dual small-diameter liquid distribution elements ensure that the refrigerant can be evenly distributed during both cooling and heating flow.

[0051] This disclosure also provides an air conditioner.

[0052] An air conditioner includes a compressor, a four-way valve, an outdoor heat exchanger, a throttling element, and an indoor heat exchanger connected in sequence to form a refrigerant circulation system, wherein the outdoor heat exchanger and / or the indoor heat exchanger are heat exchangers as described above.

[0053] This disclosure also provides a method for determining the tube diameter of a heat exchanger, including:

[0054] S01, when the refrigerant viscosity of the refrigeration system is less than or equal to the first viscosity value, the processor obtains the first coefficient a based on the target capacity E of the refrigeration system and the unit capacity e of the refrigeration system;

[0055] S02, the processor obtains the first parameter b based on the ratio of the refrigerant charge m of the refrigeration system to the first coefficient a;

[0056] S03, the processor determines the tube diameter of the heat exchanger based on the value of the first parameter b.

[0057] When selecting heat exchanger tube diameter, small-diameter tubes should not be used if the refrigerant viscosity is high and the pressure drop is large. High-viscosity refrigerant tends to maintain a laminar flow state in the flow path, making it difficult to transition to a turbulent flow state, and hindering uniform mixing of the gas and liquid phases during separation. Furthermore, high-viscosity refrigerant flows slowly in the pipes, reducing the heat exchanger's efficiency. Figure 4 As shown, when the refrigerant viscosity is less than or equal to a first viscosity value, further selection is performed. The processor obtains a first coefficient a by combining the target capacity E of the refrigeration system with the unit capacity e of the refrigeration system. The first coefficient a can be understood as a dimensionless parameter for the heat exchanger's heat exchange capacity. Then, the processor combines the refrigerant charge m of the refrigeration system with the first coefficient a to obtain a first parameter b. The first parameter b can be understood as the amount of refrigerant per unit heat exchange tube. Finally, the tube diameter of the heat exchange tube is determined by the first parameter b. When the first parameter b is small, the amount of refrigerant per unit heat exchange tube is small, requiring the selection of a small-diameter heat exchanger. Through the method provided in this embodiment, a small-diameter heat exchange tube can be selected when the refrigerant charge is small, enabling timely heat exchange of the refrigerant in the heat exchanger, thereby increasing the refrigerant flow rate within the heat exchanger and improving the heat exchanger's heat exchange efficiency.

[0058] Optionally, the first coefficient a is obtained based on the target capacity E of the refrigeration system and the unit capacity e of the refrigeration system, including: when the target capacity E of the refrigeration system is less than or equal to the first preset capacity, a = E / e*f1; when the target capacity E of the refrigeration system is greater than the first preset capacity, a = E / e*f2. Where f1 and f2 are both constants, and f1 is less than f2.

[0059] Conventional air conditioners are categorized by power rating as 1P, 1.5P, 2P, 3P, or 4P. A 1P air conditioner has a cooling capacity of 2000 kcal, which, when converted to international units, should be multiplied by 1.162, resulting in a cooling capacity of 2324W. A 2P air conditioner has a cooling capacity of 4648W. The first preset capacity is the cooling capacity of a 2P air conditioner. When the target capacity of the cooling system is less than or equal to the cooling capacity of a 2P air conditioner, a smaller coefficient should be used in the calculation. When the target capacity of the cooling system is greater than the cooling capacity of a 2P air conditioner, a larger coefficient should be used in the calculation. The unit capacity of the cooling system is set to be close to the cooling capacity of a 1P air conditioner. For example, the unit capacity e of the cooling system can be 2300, 2400, or 2500, etc.

[0060] Optionally, f1 is greater than or equal to 380 and less than or equal to 420. And / or, f2 is greater than or equal to 580 and less than or equal to 620.

[0061] For refrigeration systems with different target capabilities, different ranges of coefficients are selected. For example, when the target capability of the refrigeration system is less than or equal to the cooling capacity of a 2P air conditioner, the coefficient f1 can be 380, 390, 400, 410, or 420, etc. When the target capability of the refrigeration system is greater than the cooling capacity of a 2P air conditioner, the coefficient f2 can be 580, 590, 600, 610, or 620, etc.

[0062] In one embodiment, when the target capacity of the refrigeration system is less than or equal to the cooling capacity of the 2P air conditioner, the coefficient a = (target capacity of the refrigeration system E / 2500 * 400); when the target capacity of the refrigeration system is greater than the cooling capacity of the 2P air conditioner, the coefficient a = (target capacity of the refrigeration system E / 2500 * 600).

[0063] Optionally, determining the heat exchanger's pipe diameter based on the value of the first parameter b includes: when the first parameter b is greater than 0.6 and less than or equal to 0.9, the heat exchanger's pipe diameter is a first pipe diameter value; when the first parameter b is less than 0.6, the heat exchanger's pipe diameter is a second pipe diameter value. The first pipe diameter value is greater than the second pipe diameter value. When the first parameter b is greater than 0.5 and less than or equal to 0.9, the heat exchanger's pipe diameter is a third pipe diameter value; and when the first parameter b is less than 0.5, the heat exchanger's pipe diameter is a fourth pipe diameter value, where the third pipe diameter value is greater than the fourth pipe diameter value.

[0064] Optionally, the first pipe diameter is greater than 5 mm and less than or equal to 6 mm. The second pipe diameter is greater than 4 mm and less than or equal to 5 mm. And / or, the third pipe diameter is greater than 6 mm and less than or equal to 7 mm, and the fourth pipe diameter is greater than 5 mm and less than or equal to 6 mm.

[0065] The first parameter b is the ratio of the refrigerant charge m to the first coefficient a, which can be understood as the amount of refrigerant per unit heat exchange tube. Different tube diameter values ​​are selected based on the amount of refrigerant per unit heat exchange tube; the smaller the amount of refrigerant per unit heat exchange tube, the smaller the required tube diameter for the heat exchanger.

[0066] When the heat exchanger is an evaporator, 0.6 and 0.9 are used as comparison coefficients. When the first parameter b is greater than 0.6 and less than or equal to 0.9, the heat exchanger tube diameter is the first tube diameter value; when the first parameter b is less than 0.6, the heat exchanger tube diameter is the second tube diameter value. For example, the first tube diameter value can be 5mm, 5.5mm, or 6mm, etc., and the second tube diameter value can be 4mm, 4.5mm, or 5mm, etc.

[0067] When the heat exchanger is a condenser, 0.5 and 0.9 are used as comparison coefficients. When the first parameter b is greater than 0.5 and less than or equal to 0.9, the heat exchanger tube diameter is the third tube diameter value; when the first parameter b is less than 0.5, the heat exchanger tube diameter is the fourth tube diameter value. For example, the third tube diameter value can be 6mm, 6.5mm, or 7mm, etc. The second tube diameter value can be 5mm, 5.5mm, or 6mm, etc.

[0068] In one embodiment, when the air conditioner is in cooling mode, the indoor heat exchanger is an evaporator. When the first parameter b is greater than 0.6 and less than or equal to 0.9, the indoor heat exchanger uses a 6mm hairpin tube. When the first parameter b is less than 0.6, the indoor heat exchanger uses a 5mm hairpin tube. The outdoor heat exchanger is a condenser. When the first parameter b is greater than 0.5 and less than or equal to 0.9, the outdoor heat exchanger uses a 7mm hairpin tube. When the first parameter b is less than 0.5, the outdoor heat exchanger uses a 6mm hairpin tube.

[0069] Optionally, the first viscosity value includes 145-150 μPa·s.

[0070] High-viscosity refrigerants tend to maintain a laminar flow state in the flow path, making it difficult to transition to a turbulent flow state. This hinders uniform mixing of the gas and liquid phases during separation. Furthermore, high-viscosity refrigerants flow slowly in pipelines, reducing the heat exchanger's efficiency. Therefore, a primary viscosity value is required. Subsequent pipe diameter calculations and selections are only performed when the refrigerant viscosity is less than or equal to this primary viscosity value. Conversely, lower refrigerant viscosity results in lower flow resistance during refrigerant circulation in the refrigeration system, reducing cycle power consumption, allowing for the matching of smaller diameter heat exchange tubes, and also reducing the impact force of the refrigerant on the compressor's valve assembly, thus extending the compressor's service life.

[0071] Optionally, the method for determining the tube diameter of the heat exchanger further includes: obtaining a branch number threshold y of the heat exchanger based on the tube diameter r, the length s of the heat exchange tubes, and the number of heat exchange tubes x; and obtaining a reasonable number of branches Y of the heat exchanger based on the branch number threshold y. Wherein, Y is greater than or equal to y.

[0072] Alternatively, y = r 2 *s*x / q / b. Where q is a constant.

[0073] In the heat exchanger provided in this embodiment, the diameter of the heat exchange tubes is relatively small. Correspondingly, the heat exchange tube piping design requires a larger number of heat exchange branches to improve the heat exchanger's efficiency. Here, q is a constant, taking the value 210000 or 100000. r is the radius of the heat exchange tube, s is the length of the heat exchange tube, and x is the number of heat exchange tubes. (r 2 *s*x) represents the volume of the heat exchanger. (b*q) is the minimum heat exchanger volume corresponding to one heat exchange branch. y = r 2 The minimum number of heat exchange branches is obtained by calculating *s*x / q / b.

[0074] The heat exchanger provided in this embodiment is obtained by the aforementioned method for determining the tube diameter of the heat exchanger.

[0075] The foregoing description and accompanying drawings fully illustrate embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Parts and features of some embodiments may be included or substituted for parts and features of other embodiments. Embodiments of the present disclosure are not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from its scope. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A method for determining the tube diameter of a heat exchanger, characterized in that, include: When the refrigerant viscosity of the refrigeration system is less than or equal to a first viscosity value, a first coefficient a is obtained based on the target capacity E of the refrigeration system and the unit capacity e of the refrigeration system. When the target capacity E of the refrigeration system is less than or equal to a first preset capacity... When the target capacity E of the refrigeration system is greater than the first preset capacity, Where f1 and f2 are both constants, and f1 is less than f2; the unit capacity e is set to be close to the cooling capacity of a 1P air conditioner. The first parameter b is obtained based on the ratio of the refrigerant charge m of the refrigeration system to the first coefficient a. The tube diameter of the heat exchanger is determined based on the value of the first parameter b. When the heat exchanger is an evaporator, and the first parameter b is greater than 0.6 and less than or equal to 0.9, the tube diameter of the heat exchanger is the first tube diameter value; and when the first parameter b is less than 0.6, the tube diameter of the heat exchanger is the second tube diameter value, wherein the first tube diameter value is greater than the second tube diameter value. When the heat exchanger is a condenser, and the first parameter b is greater than 0.5 and less than or equal to 0.9, the tube diameter of the heat exchanger is the third tube diameter value; and when the first parameter b is less than 0.5, the tube diameter of the heat exchanger is the fourth tube diameter value, wherein the third tube diameter value is greater than the fourth tube diameter value.

2. The method according to claim 1, characterized in that, f1 is greater than or equal to 380 and less than or equal to 420; and / or, f2 is greater than or equal to 580 and less than or equal to 620.

3. The method according to claim 1, characterized in that, The first pipe diameter is greater than 5 mm and less than or equal to 6 mm, and the second pipe diameter is greater than 4 mm and less than or equal to 5 mm; and / or, The third pipe diameter is greater than 6 mm and less than or equal to 7 mm, and the fourth pipe diameter is greater than 5 mm and less than or equal to 6 mm.

4. The method according to any one of claims 1 to 3, characterized in that, The first viscosity value includes 145-150 μPa·s.

5. The method according to claim 4, characterized in that, Also includes: Based on the tube diameter r, the tube length s, and the number of tubes x, the threshold y for the number of branches in the heat exchanger is obtained. The reasonable number of branches Y for the heat exchanger is obtained based on the aforementioned branch number threshold y. Where Y is greater than or equal to y.

6. The method according to claim 5, characterized in that, ， Where q is a constant.

7. A heat exchanger, characterized in that, The heat exchanger is obtained by the method for determining the tube diameter of the heat exchanger as described in any one of claims 1 to 6.

8. An air conditioner, characterized in that, include: The compressor, four-way valve, outdoor heat exchanger, throttling element, and indoor heat exchanger are connected in sequence to form a refrigerant circulation system. Wherein, the outdoor heat exchanger and / or the indoor heat exchanger are the heat exchangers as described in claim 7.

Images