Novel refrigerant distributor, heat exchanger assembly and refrigeration equipment

Abstract

The application provides a novel refrigerant distributor, a heat exchanger assembly and a refrigeration device. The novel refrigerant distributor comprises a distributor body and a plurality of branch pipes. A distribution area is formed in the distributor body downstream of an inlet end. A plurality of distribution holes are formed in the outlet end of the distributor body and are communicated with the distribution area. The plurality of branch pipes are respectively welded to the plurality of distribution holes. Each branch pipe comprises at least one accelerating section with a decreasing inner diameter along the direction of refrigerant flow in the branch pipe and a branch pipe connecting section upstream of the accelerating section. The difference △d between the inner diameter d1 at the downstream end of the branch pipe connecting section and the inner diameter d2 at the downstream end of the accelerating section is 0.1mm≤△d≤3.5mm. An attenuation section is formed in the branch pipe connecting section and extends to one side of the center line of the distribution hole. The intersection between the axis at the upstream end of the attenuation section and the axis at the downstream end of the attenuation section forms an included angle α and 90°≤α≤175°. The axis of the accelerating section intersects the center line of the distribution hole.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigerant distribution, and in particular to a novel refrigerant distributor, a heat exchanger assembly and a refrigeration device. Background Art

[0002] In a compression refrigeration system, the two-phase refrigerant flows into the distributor after passing through the expansion valve and is distributed to the various branches of the evaporator. Ideally, the distributor can provide equal and uniform amounts of refrigerant to each branch. However, in actual operation, it is often the case that the liquid supply of each branch is different, and the gas-liquid two-phase refrigerant flows into each branch unevenly and in unequal amounts. In order to solve the problem of uneven refrigerant distribution, those skilled in the art have conducted a lot of research on the distributor, the main component of refrigerant distribution. At present, research in this area mainly focuses on the optimization of the flow channel and distribution chamber in the distributor body (such as reducing the cross-sectional area in the distribution chamber) and the improvement of the liquid inlet pipe, so that the refrigerant can be fully mixed before distribution through optimization. However, these optimizations are all aimed at the research before the refrigerant is distributed, and few people have studied the refrigerant after it is distributed to the various branches.

[0003] At present, the improvement on the liquid outlet side of the distributor mainly solves the problem of branch pipe welding assembly, such as the assembly interference of multiple branches and the quality problem of branch pipe welding. Some people have proposed to set the branch pipe as a bend to avoid spatial interference during the assembly of multiple branches, and at the same time, to be compatible with heat exchanger capillaries of different specifications, a sleeve is also set at the end of the branch pipe. Although this solution solves the problem of branch pipe assembly, it completely ignores the problem of deterioration of refrigerant distribution performance caused by the bending of the branch pipe and the assembly step of the capillary tube on the sleeve. Specifically, in order to solve the problem of spatial interference, it is necessary to control the bending angle of the branch pipe (the angle between the central axis of the pipe section before bending and the central axis of the pipe section after bending) so that the pipe section after bending is farther away from other branches; and the bending of the pipe will inevitably cause refrigerant pressure loss and the smaller the bending angle, the greater the pressure loss. At the same time, the refrigerant will also hit the capillary assembly step on the sleeve during flow, generating vortices at the step. The vortex forms a high-pressure area and squeezes the flow channel cross-sectional area there, making it difficult for the refrigerant to pass through the step and enter the capillary tube. This not only seriously affects the refrigerant flow in the heat exchanger capillary tube, but also causes a sharp increase in refrigerant pressure loss. Excessive pressure loss will lead to a low average evaporation temperature in the evaporator, reducing the operating efficiency of the system.

[0004] In addition, some people have proposed to solve the problems of branch pipe welding blockage, welding deformation or leakage by adjusting the branch pipe diameter at the distribution port. At the same time, it is also hoped that a larger diameter distribution port can reduce the problem of uneven refrigerant distribution near the branch pipe hole. However, due to the requirements of the heat exchanger for the refrigerant flow rate, a larger diameter branch pipe must be connected to a smaller diameter capillary tube or an additional atomizing nozzle 400 (such as Figure 1), the flow channel is reduced to increase the flow rate of the refrigerant. However, the reduction of the flow channel will inevitably cause the refrigerant to be throttled, which will not only cause pressure loss, but also cause the pressure wave caused by the change of the refrigerant pressure after throttling to appear at the throttling position. The pressure wave will be transmitted upstream along the branch pipe to the distribution port of the body, which will hinder the flow of the refrigerant at the distribution port and also affect the atomization state of the refrigerant in the distributor body, thereby seriously affecting the distribution performance.

[0005] The purpose of setting the distributor is to improve the performance of the heat exchanger based on the distribution performance of the distributor. The distribution performance of the distributor is affected by the mixing degree of the two-phase flow in the distributor body, the pressure drop loss of the refrigerant during distribution, the flow rate of the refrigerant after distribution, and the disturbance of the pressure wave downstream, etc. The influence of any one factor may offset the effect of improving the other factors, thereby causing the performance of the heat exchanger to deteriorate. Therefore, it is urgent to improve the structure of the distributor outlet side to solve the influence of the refrigerant pressure loss, flow rate and pressure wave disturbance on the performance of the heat exchanger. SUMMARY

[0006] The present application provides a novel refrigerant distributor, a heat exchanger assembly and a refrigeration equipment to overcome the shortcomings of the prior art.

[0007] In order to achieve the above-mentioned purpose, the present application provides a novel refrigerant distributor, which comprises a distributor body and a plurality of distribution branch pipes. The distributor body comprises an inlet end and an outlet end, and a distribution area is formed in the distributor body downstream of the inlet end. A plurality of distribution holes are formed in the outlet end of the distributor body and communicate with the distribution area. The plurality of distribution branch pipes are respectively welded to the plurality of distribution holes. Each distribution branch pipe comprises at least one acceleration section with a reduced inner diameter along the direction of refrigerant flow in the distribution branch pipe and a branch pipe connecting section upstream of the acceleration section. The difference Δd between the inner diameter d1 at the downstream end of the branch pipe connecting section and the inner diameter d2 at the downstream end of the acceleration section is: 0.1mm≤Δd≤3.5mm. The branch pipe connecting section is formed with an attenuation section extending to one side of the center line of the distribution hole. The intersection between the upstream end of the attenuation section and the downstream end of the attenuation section forms an included angle α, and 90°≤α≤175°. Based on the attenuation section, the axis of the acceleration section intersects the center line of the distribution hole.

[0008] According to an embodiment of the present application, the branch pipe connecting section further comprises a transition section downstream of the attenuation section to connect the acceleration section, and the transition section extends along the axis at the downstream end of the attenuation section.

[0009] According to an embodiment of the present application, along the direction of refrigerant flow in the distribution branch pipe, the length L of the straight section from the beginning of the bending of the attenuation section to the end face of the branch pipe connecting section connected to the distribution hole is: 3mm≤L≤150mm.

[0010] According to one embodiment of the present invention, the speed increasing section is a tapered structure integrally formed with the branch pipe connecting section and having a gradually decreasing inner diameter; each branch pipe further includes a branch section.

[0011] The branch section is welded to the speed-increasing section, or the branch pipe connecting section, the speed-increasing section and the branch section are formed as one piece.

[0012] According to an embodiment of the present invention, each branch pipe further includes a branch section welded to the downstream of the branch pipe connecting section, and the speed increasing section is formed at the welding position of the branch section or on the branch section.

[0013] According to one embodiment of the present invention, the inner diameter of the branch section located downstream of the speed-increasing section is substantially close to the inner diameter of the downstream end of the speed-increasing section;

[0014] Alternatively, the inner diameter of the branch section downstream of the speed-increasing section is larger than the inner diameter at the downstream end of the speed-increasing section, and the speed-increasing section has a straight section with a substantially constant inner diameter.

[0015] According to one embodiment of the present invention, the branch section is a straight pipe gradually extending along the axis direction of the downstream end of the speed increasing section; or, the branch section is a curved pipe extending to one side relative to the axis of the downstream end of the speed increasing section.

[0016] According to one embodiment of the present invention, each diversion hole includes a pipe hole section welded to the corresponding branch pipe connection section and a drainage hole section connecting the pipe hole section and the distribution area, and the inner diameter of the drainage hole section gradually decreases along the refrigerant flow direction.

[0017] According to one embodiment of the present invention, a guide section whose inner diameter gradually decreases along the refrigerant inflow direction is formed on one end of the branch pipe connecting section connected to the diversion hole, and the inner wall generatrix of the guide section is an inclined straight line or an arc curve.

[0018] According to an embodiment of the present invention, the axis of each diversion hole is substantially parallel to the axis of the distributor body.

[0019] On the other hand, the present invention also provides a heat exchanger assembly, which includes the above-mentioned novel refrigerant distributor.

[0020] On the other hand, the present invention further provides a refrigeration device comprising the above-mentioned heat exchanger assembly.

[0021] In summary, in the new refrigerant distributor provided by the present invention, each branch pipe includes a branch pipe connecting section and an increasing speed section located downstream of the branch pipe connecting section. The branch pipe connecting section with a larger inner diameter increases the refrigerant flow rate distributed to each branch pipe and reduces the refrigerant distribution resistance; while the increasing speed section increases the refrigerant flow rate by reducing the flow channel cross section. On this basis, the degree of pressure reduction and acceleration of the refrigerant by the increasing speed section is accurately controlled by setting the inner diameter difference △d to avoid excessive fluid pressure loss due to excessive throttling, thereby achieving balanced control of flow rate, flow rate and pressure during refrigerant distribution. Furthermore, by setting an attenuation portion that bends and extends to one side relative to the center line of the diversion hole on the branch pipe connecting section, the increasing speed section is no longer coaxial with the center line of the diversion hole. When the pressure wave generated by the refrigerant's velocity and pressure changes in the speed-increasing section propagates upstream, a portion of the pressure wave is reflected and absorbed by the outer inner wall of the attenuation section, while the other portion bends at the attenuation section and rapidly decays after undergoing a conversion in propagation mode. This effectively addresses the issue of reduced refrigerant flow and velocity at the diverter hole caused by downstream pressure wave oscillations, effectively improving the diversion performance of the refrigerant distributor. Furthermore, to balance the refrigerant pressure loss caused by the bending of the attenuation section and the impact strength of the outer inner wall of the attenuation section, the axis at the upstream end of the attenuation section and the axis at the downstream end of the attenuation section intersect to form an angle α, with a value of 90°≤α≤175°.

[0022] In order to make the above and other objects, features and advantages of the present invention more clearly understood, preferred embodiments are given below with reference to the accompanying drawings for detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Shown is a structural schematic diagram of an existing refrigerant distributor.

[0024] Figure 2 Shown is a structural schematic diagram of a new refrigerant distributor provided in Example 1 of the present invention.

[0025] Figure 3 Shown Figure 2 Schematic diagram of the structure of the middle branch pipe.

[0026] Figure 4 Shown Figure 3 Enlarged schematic diagram of point A in the middle.

[0027] Figure 5 、 Figure 6 、 Figure 7 as well as Figure 8 FIG2 is a schematic structural diagram of a branch pipe in a novel refrigerant distributor provided by another embodiment of the present invention.

[0028] Figure 9 Shown Figure 2 Schematic diagram of the structure after removing the liquid inlet pipe and multiple branch pipes.

[0029] Figure 10 Shown Figure 9 Enlarged schematic diagram of point B in the middle.

[0030] Figure 11 Shown is a structural schematic diagram of a novel refrigerant distributor provided by another embodiment of the present invention.

[0031] Figure 12 Shown is a structural schematic diagram of a new refrigerant distributor provided in Example 2 of the present invention.

[0032] Figure 13 、 Figure 14 as well as Figure 15 FIG2 is a schematic structural diagram of a branch pipe in a novel refrigerant distributor provided by another embodiment of the present invention.

[0033] Figures 16 to 18 Shown is a structural schematic diagram of a novel refrigerant distributor provided by another embodiment of the present invention.

[0034] Figure 19 Shown is a structural schematic diagram of a new refrigerant distributor provided in Example 3 of the present invention.

[0035] Figure 20 Shown is a structural schematic diagram of a new refrigerant distributor provided in Example 4 of the present invention. DETAILED DESCRIPTION

[0036] Example 1

[0037] Compared with single-phase flow, the mechanism of action of gas-liquid two-phase refrigerant during transmission and distribution within the distributor is more complex. The performance of the distributor is closely related to factors such as the refrigerant flow pattern in its liquid inlet pipe, the degree of atomization of the refrigerant in the distributor body, and the refrigerant flow properties on the liquid outlet side. At present, research on distributor performance is mainly focused on the distributor body and the liquid inlet pipe, while improvements to the liquid outlet structure of the distributor mainly address the assembly and welding problems of multiple branches. In fact, factors such as the pressure drop loss of the refrigerant on the liquid outlet side, the flow rate of the refrigerant after distribution, and the downstream pressure wave disturbance will have a great impact on the distribution performance of the distributor.

[0038] In view of this, this embodiment provides a new type of refrigerant distributor based on the improvement of the liquid outlet side structure to enhance the performance of the distributor. Figures 2 to 4As shown, this embodiment provides a refrigerant distributor including a distributor body 1 and a plurality of branch pipes 2. The distributor body 1 includes a liquid inlet 101 and a liquid outlet 102. A distribution area 103 is formed in the distributor body 1 and is located downstream of the liquid inlet 101. The liquid outlet 102 of the distributor body is formed with a plurality of branch holes 104 that communicate with the distribution area 103. The plurality of branch pipes 2 are respectively welded to the plurality of branch holes 104. Each branch pipe 2 includes at least one speed-increasing section 22 whose inner diameter decreases along the refrigerant flow direction within the branch pipe 2, and a branch pipe connecting section 21 located upstream of the speed-increasing section 22. The difference Δd between the inner diameter d1 at the downstream end of the branch pipe connecting section 21 and the inner diameter d2 at the downstream end of the speed-increasing section 22 is: 0.1mm≤Δd≤3.5mm. A damping section 211 is formed on the branch pipe connecting section 21, curving and extending toward the centerline of the diverter hole 104. The axis lines at the upstream and downstream ends of the damping section 211 intersect at an angle α with a range of 90°≤α≤175°. The axis line of the speed-increasing section 22 intersects the centerline of the diverter hole 104 based on the damping section 211.

[0039] In this embodiment, there are four branch pipes 2, and each branch pipe 2 is formed with a decaying section 211 and a speed increasing section 22. However, the present invention is not limited to this. In other embodiments, the number of branch pipes can be two, three, or five or more.

[0040] In this application, the terms "downstream" and "upstream" are defined based on the direction of refrigerant flow. Generally, refrigerant flows from upstream to downstream, with the downstream area receiving refrigerant from upstream. In refrigeration equipment, the distributor is typically installed vertically or tilted, with the liquid inlet located below the liquid outlet along the direction of gravity. The inertial force of the refrigerant in the distributor overcomes gravity and flows in the direction opposite to gravity. In this case, upstream and downstream are still defined based on the direction of refrigerant flow.

[0041] In the refrigeration system, the new refrigerant distributor provided in this embodiment is connected between the throttle valve and the evaporator. The gas-liquid two-phase refrigerant after the throttle valve reduces the pressure and evaporates enters the distributor body and is fully mixed. It is then distributed to the various branches of the evaporator through multiple branch pipes 2. Limited by the evaporation temperature and heat transfer coefficient, the pressure loss and flow rate in each branch pipe of the distributor need to meet certain requirements. Specifically, excessive pressure loss on the liquid outlet side of the distributor will cause the liquid refrigerant to evaporate prematurely, thereby affecting the flow rate of refrigerant entering the evaporator and causing the average evaporation temperature of the evaporator to be too low; when the condensing temperature remains unchanged, the reduction in evaporation temperature will increase the pressure ratio of the compressor and cause the compressor power to increase. If the refrigerant flow rate is too low, the heat transfer coefficient of the evaporator will be too small, which will increase the heat transfer temperature difference and irreversible loss and affect the energy efficiency of the refrigeration system.

[0042] Therefore, in order to take into account the pressure loss and flow rate of the refrigerant distributed to each branch pipe, the new refrigerant distributor provided in this embodiment is provided with each branch pipe 2 including a branch pipe connecting section 21 connected to the diversion hole 104 and a speed-increasing section 22 located downstream of the branch pipe connecting section 21 and having an inner diameter smaller than that of the branch pipe connecting section 21. The branch pipe connecting section 21 with a larger inner diameter increases the refrigerant distribution flow channel between the distribution area 103 and the branch pipe 2 in the distributor body 1, increasing the refrigerant flow while reducing the pressure loss of the refrigerant distribution. To compensate for the problem of reduced refrigerant flow rate caused by the increase in the inner diameter of the branch pipe connecting section 21, the speed-increasing section 22 reduces the pressure and speeds up the refrigerant by reducing the inner diameter. On this basis, the difference Δd between the inner diameter d2 of the downstream end of the speed-increasing section 22 and the inner diameter d1 of the downstream end of the branch pipe connecting section 21 (hereinafter referred to as the inner diameter difference Δd for ease of description) is controlled to accurately control the degree of throttling of the refrigerant by the speed-increasing section 22, thereby avoiding a sharp increase in the refrigerant pressure loss due to excessive throttling. This setting realizes the comprehensive control of refrigerant flow rate and refrigerant pressure loss, ensures that the heat transfer coefficient of the evaporator and its average evaporation temperature are evenly within the design range of the evaporator, and comprehensively improves the heat transfer performance of the evaporator.

[0043] Furthermore, according to the Bernoulli equation, when the refrigerant flows through the speed-increasing section 22, its gas pressure value will drop to a very low level. When the refrigerant pressure value at the speed-increasing section 22 is lower than the saturated vapor pressure of the refrigerant, the gas nuclei in the refrigerant will grow into cavitation bubbles. Afterwards, the cavitation bubbles collapse and produce cavitation. Intense cavitation will cause large-scale pipeline vibration accompanied by noise, that is, form pressure waves. The pressure wave is transmitted upstream and downstream along the branch pipe 2. When the pressure wave is transmitted upstream to the distributor body 1, it not only directly affects the refrigerant distribution flow and flow rate at the diversion hole 104, but also affects the degree of mixed atomization of the refrigerant in the distribution area 103, thereby seriously affecting the two-phase flow distribution process and worsening the phase separation phenomenon. In order to reduce the impact of the pressure wave on the upstream refrigerant distribution, the new refrigerant distributor provided in this embodiment controls the throttling degree of the speed-increasing section 22 through the inner diameter difference Δd to achieve the lowest pressure value of the refrigerant at this location and minimize the pressure wave energy caused by cavitation. On the other hand, an attenuation section 211 is formed on the branch pipe connecting section 21, which is bent and extended to one side relative to the center line of the diversion hole 104. The setting of the attenuation section 211 makes the speed-increasing section 22 no longer coaxial with the diversion hole 104. When the pressure wave generated at the speed-increasing section 22 is transmitted upstream to the attenuation section 211, a part of it is reflected back to the downstream through the outer inner wall of the attenuation section 211 (referring to the inner wall of the attenuation section 211 that is farthest from the center of the bending circle in the radial direction) and is absorbed at the same time as the reflection; while the other part turns at the attenuation section 211 and changes the propagation form of the pressure wave, making it easier to be absorbed by the branch pipe connecting section 21, thereby accelerating the attenuation speed of the pressure wave when it is transmitted upstream. This setting effectively reduces the impact of the pressure wave on the refrigerant performance at the diversion hole 104, thereby greatly improving the diversion performance of the distributor.

[0044] Based on the influence of throttling intensity on the average evaporation temperature and pressure wave of the evaporator, the inner diameter difference △d in this embodiment is set to satisfy: 0.1mm≤△d≤3.5mm. Specifically, the inner diameter d1 at the downstream end of the branch pipe connecting section 21 is set to 5.5mm, the inner diameter d2 at the downstream end of the speed increasing section 22 is set to 5mm, and the inner diameter difference △d is 0.5mm. However, the present invention does not impose any limitation on this. In other examples, the inner diameter difference △d can also be set to other values ​​within 0.1mm≤△d≤3.5mm, such as 0.2mm, 1mm, 1.5mm, 2mm, 2.5mm and 3mm. Although this embodiment is described by taking the inner diameter d1 at the downstream end of the branch pipe connecting section 2 as 5.5mm as an example. However, the present invention does not impose any limitation on this. In other embodiments, d1 can also be other pipe diameter specifications, such as other pipe diameter specifications within 3mm~10mm.

[0045] For the attenuation section 211, the curved structure enables it to reflect and absorb pressure waves and change the propagation mode of the pressure waves so that the pressure waves decay rapidly after passing through the attenuation section 211. However, the curved structure is bound to bring about local resistance loss. In order to reduce the local resistance loss at the attenuation section 211, the bending angle of the attenuation section 211 is controlled. Specifically, the axis at the upstream end of the attenuation section 211 and the axis at the downstream end of the attenuation section 211 are arranged to intersect to form an angle α and 90°≤α≤175°. Furthermore, since the reflection and absorption of the pressure wave mainly act on the outer inner wall of the attenuation section 211, the setting of the angle α also needs to take into account the thickness of the outer pipe wall of the attenuation section 211 to ensure that it meets the system pressure resistance and service life requirements while also meeting the reflection impact of the pressure wave.

[0046] In order to study the effect of the bending angle of the attenuation section 211 on the pressure wave attenuation and local resistance loss, a CFD (computational fluid dynamics) simulation was conducted. Figure 2 The new refrigerant distributor shown in the figure is subjected to flow distribution uniformity and pressure loss analysis. When other structural parameters remain the same, the following schemes are selected based on the angle α: 180°, 175°, 172°, 170°, 168°, 165°, 162°, 160°, 155°, 150°, 140°, 135°, 130°, 120°, 110°, 100°, 90° and 85°. After simulation, Table 1 is formed. Among them, △P is the pressure difference between the refrigerant pressure at the liquid inlet hole 105 and the total outlet pressure in the new refrigerant distributor; STD is the evaluation index, which is the mean square deviation of the refrigerant mass flow rate at each branch outlet, and its expression is as follows:

[0047]

[0048] in, is the average refrigerant mass flow rate of all branch outlets, xj is the outlet refrigerant mass flow rate of the jth branch, and n is the number of branches.

[0049] The software used for CFD simulation analysis is ANSYS software, and its conditions are set as follows:

[0050] Turbulence model: Realizable k-ε model;

[0051] Network parameters: Tetrahedral unstructured grid is used;

[0052] Working conditions: The working fluid is R410A refrigerant, the wall boundary is an adiabatic boundary, the inlet dryness is 0.2, and the installation condition is vertical installation;

[0053] Inlet boundary conditions: inlet total mass flow rate: 120 kg / h; inlet gas phase velocity: 3.92 m / s; inlet liquid phase velocity: 0.46 m / s; liquid phase volume fraction: 0.1032; turbulence intensity: 5%; hydraulic diameter value: 8.12 mm.

[0054] Table 1

[0055]

[0056]

[0057] Based on the data in Table 1, adjusting the angle α from 180° to 175° increases the flow uniformity (STD) by 39.6%, significantly improving flow uniformity. When the angle α is adjusted to 165°, the STD increases by 68.3%. The data in Table 1 demonstrate that the installation of attenuation section 211 significantly improves distributor performance. Furthermore, examining the pressure difference ΔP in Table 1 reveals that the attenuation section 211 has little overall impact on the pressure difference ΔP. The pressure difference ΔP for angles between 162° and 175° is even slightly lower than when α is 180°. This is likely due to the beneficial effect of attenuation section 211, which effectively reduces the impact of downstream pressure waves on upstream refrigerant transmission. However, as the angle α decreases, the pressure difference ΔP increases, and the closer the angle α approaches 90°, the faster the increase. Furthermore, when the angle α is less than 90°, the flow uniformity STD deteriorates sharply.

[0058] In combination with the liquid separation performance in Table 1 and taking into account the effect of the angle α on the thickness of the outer tube wall of the attenuation section 211, it is preferred to set the angle α to an angle value within 170° to 140°, such as 165°, 162°, 140°, etc. However, the present invention does not impose any limitation on this. In other embodiments, when the overall pressure loss of the distributor and the thickness of the outer tube wall of the attenuation section allow, the angle α can also be set to other values ​​within 90°≤α≤175°. The wall thickness of the outer tube wall of the attenuation section refers to the wall thickness of the attenuation section tube wall farthest from the center of the bending circle in the radial direction.

[0059] In order to further reduce the impact of the downstream pressure wave on the flow pattern and flow state of the refrigerant in the diverter hole 104 and the distribution area 103, this embodiment sets the straight section length L from the point K where the attenuation section 211 begins to bend relative to the center line of the diverter hole to the end face where the branch pipe connecting section 21 is connected to the diverter hole 104 along the refrigerant flow direction in the diverter branch pipe 2: 3mm≤L≤150mm. Although the downstream pressure wave is rapidly attenuated after being reflected and absorbed by the attenuation section 211 and the propagation form is transformed, when the pressure wave energy is large or the angle α is large, the remaining pressure wave after attenuation will inevitably continue to transmit upstream. Therefore, this embodiment provides an attenuation distance for the pressure wave by setting the straight section length L to ensure that the pressure wave is completely attenuated before being transmitted to the diverter hole 104, thereby effectively solving the impact of the downstream pressure wave on the refrigerant in the distributor body 1.

[0060] Furthermore, the setting of the straight section length L also provides a wider design space for the angle α. Specifically, when the angle α is limited by factors such as local resistance loss or the wall thickness of the attenuation section 211 and is at a larger angle, the reflection and absorption effect of the inner wall of the attenuation section 211 on the pressure wave is weakened. In this case, the straight section length L can be increased to compensate for it to ensure that the pressure wave is completely attenuated before it is transmitted to the diversion hole; and when the angle α is relatively small, the straight section length L can be shortened to control the axial length of the new refrigerant distributor. The combination of the angle α and the straight section length L makes the new refrigerant distributor provided in this embodiment not only have excellent performance but also can be well installed in a narrow or short axial length installation space, greatly improving the compatibility of the distributor with the installation space. Preferably, the straight section length L can be set to 30mm or 50mm. However, the present invention does not impose any limitation on this. In other embodiments, the straight section length L can also be any length value within 3mm≤L≤150mm.

[0061] In this embodiment, the branch pipe connecting section 21 also includes a transition section 212 located downstream of the attenuation section 211 to connect to the speed increasing section 22. The transition section 212 extends along the axial direction of the downstream end of the attenuation section 211, and the inner diameter d1 at the downstream end of the branch pipe connecting section is the inner diameter at the downstream end of the transition section 212. Similarly, the absorption of pressure waves by the transition section 212 can also weaken the energy transmitted upstream by the pressure wave, weaken the impact of the pressure wave on the outer peripheral wall of the attenuation section 211, and improve the pressure resistance and service life of the attenuation section 211. In addition, in other embodiments, the transition section 212 also provides an assembly position for the welding connection of the rear end branch section. However, the present invention does not impose any limitation on this. In other embodiments, there is no need to set a transition section on the branch pipe connecting section. Figure 5 shown.

[0062] In this embodiment, the speed-increasing section 22 is integrally formed with the branch pipe connecting section 21 and has a tapered structure with a gradually decreasing inner diameter. This tapered structure allows the refrigerant to smoothly flow from the branch pipe connecting section 21 into the speed-increasing section 22. This arrangement not only reduces the refrigerant flow resistance but also effectively weakens the high-pressure vortex generated by the sudden change in the flow channel cross-section, preventing the flow channel in the speed-increasing section 22 from being occupied by the high-pressure vortex. This ensures that the actual effective flow channel cross-sectional area in the speed-increasing section 22 is substantially close to the designed value, thereby promoting smooth refrigerant flow. However, the present invention is not limited to this.

[0063] In this embodiment, each branch pipe 2 further includes a branch section 23, and the inner diameter of the branch section 23 is substantially close to the inner diameter d2 at the downstream end of the speed increasing section 22. Specifically, in this embodiment, the branch pipe connecting section 21, the speed increasing section 22 and the branch section 23 are integrally formed, and the branch section 23 is a straight pipe that gradually extends along the axial direction of the downstream end of the speed increasing section 22. However, the present invention does not impose any limitation on this. In other embodiments, the branch section 23 can also be welded to the assembly section 221 downstream of the speed increasing section 22, such as Figure 6 In addition, the new refrigerant distributor does not need to be provided with a branch section, and the system pipeline of the refrigeration equipment can be directly connected to the assembly section 221 downstream of the speed increasing section 22, as shown. Figure 7 In addition, the branch section 23 can also be a curved pipe that bends and extends to one side relative to the axis of the downstream end of the speed increasing section 22, as shown in FIG. Figure 8 shown.

[0064] Specifically, during the process of the high-speed refrigerant entering from the liquid inlet end 101 being fully mixed in the distribution area 103 and distributed to multiple branch pipes 2, part of the refrigerant will inevitably collide with the end wall of the distribution area 103 near the liquid outlet end and reflux along the peripheral wall of the distribution area 103. The reflux of the refrigerant will generate an eddy zone near the diversion hole 104. The existence of the eddy zone will squeeze the refrigerant flow channel at the entrance of the diversion hole 104 and reduce the refrigerant flow rate entering the diversion branch pipe 2, thereby affecting the diversion performance of the distributor. In order to reduce the adverse effect of the eddy zone near the diversion hole 104 on the diversion performance, as shown in FIG. Figure 9 and Figure 10 As shown, in this embodiment, each diversion hole 104 includes a pipe hole section 1042 welded to the corresponding branch pipe connection section 21 and a drainage hole section 1041 connecting the pipe hole section 1042 and the distribution area 103. The inner diameter of the drainage hole section 1041 gradually decreases along the flow direction of the refrigerant. Under the premise that the inner diameter of the pipe hole section 1042 remains unchanged, the gradual reduction in the aperture of the drainage hole section 1041 will inevitably increase the aperture at the entrance of the drainage hole section 1041 (that is, increase the refrigerant flow channel at the entrance of the diversion hole 104), so that the refrigerant can better enter the drainage hole section 1041. In addition, the increase in the aperture at the entrance of the drainage hole section 1041 also reduces the reflection area of ​​the refrigerant near the end wall of the distribution area 103 near the liquid outlet end, thereby reducing the scope of action of the vortex zone and weakening its squeezing of the refrigerant distribution channel, thereby further improving the diversion uniformity and reducing the diversion resistance.

[0065] Furthermore, in this embodiment, the downstream end of the drainage hole section 1041 has a smaller diameter than the pipe hole section 1042. A stopper 1043 protrudes toward the center of the diverter hole 104 at the junction of the drainage hole section 1041 and the pipe hole section 1042. The inner diameter d3 of the stopper 1043 is substantially close to the inner diameter d4 of the diverter pipe 2. The stopper 1043 is configured to abut the insertion end surface of the diverter pipe 2 to achieve insertion and assembly limit for the diverter pipe 2. The fact that the inner diameter d3 of the stopper 1043 is substantially close to the inner diameter d4 of the diverter pipe eliminates a step at the insertion front end surface of the diverter pipe 2. This allows the refrigerant flowing into the drainage hole section 1041 to smoothly enter the diverter pipe 2, further reducing the refrigerant's flow resistance.

[0066] In this embodiment, the branch pipe connecting section 21 is a circular pipe with a substantially uniform inner diameter. However, the present invention does not impose any limitation on this. In other embodiments, the branch pipe connecting section 21 may be provided with a guide section 213 whose inner diameter gradually decreases along the refrigerant inflow direction on one end connected to the diversion hole 104, and the inner wall generatrix of the guide section 213 is an inclined straight line (such as Figure 11 Similar to the drainage hole section 1041, the diversion section 213 can also guide the refrigerant to better enter the branch pipe 2 to reduce the distribution resistance of the refrigerant.

[0067] In this embodiment, the axis of each diversion hole 104 is substantially parallel to the axis of the distributor body 1. However, the present invention is not limited thereto.

[0068] like Figure 2 As shown, the new refrigerant distributor provided in this embodiment is a distributor structure that integrates reflection and mixing. The new refrigerant distributor also includes a partition 3 arranged in the distribution area 103. A cavity 301 with an opening toward the liquid inlet is formed on the partition 3 in the area opposite to the liquid inlet hole (assembled with the liquid inlet pipe 4, so it is not marked), and the partition 3 at the cavity 301 protrudes and extends toward the side where the liquid outlet end 102 of the body is located. The partition 3 divides the distribution area 103 into a reflection mixing area 1031 close to the liquid inlet end 101 and including the cavity 301, and a mixing distribution area 1032 close to the liquid outlet end 102. A plurality of partition holes 31 are formed on the partition 3, which are distributed in an annular manner around the axis of the distributor body 1 and connect the reflection mixing area 1031 and the mixing distribution area 1032. The plurality of partition holes 31 are configured to correspond one to one with the plurality of diversion holes 104, and when projected along the axial direction of the distributor body 1, the plurality of partition holes 31 are located on the periphery of the liquid inlet hole.

[0069] In the novel refrigerant distributor combining reflection and mixing, provided in this embodiment, high-speed two-phase refrigerant is fed into the concave cavity 301 through the liquid inlet port on the liquid inlet end 102. After being blocked and reflected by the bottom wall of the concave cavity 301, it is fully mixed into a dispersed state in the reflection mixing zone 1031. It then flows along the multiple baffle holes 31 on the baffle 3 into the mixing and distribution zone 1032. Within this zone, it is further mixed before being evenly distributed through the diversion holes 104 to the branch pipe connection section 21 of each branch pipe 2. The refrigerant then passes through the attenuation section 211 and reaches the speed-increasing section 22, where it is decompressed and accelerated before being delivered to the evaporator. In each branch pipe 2, by setting the inner diameter difference △d and the attenuation part 211 related to the speed increasing section 22, the problems of excessive pressure loss caused by excessive throttling of the speed increasing section 22 and the transmission of pressure waves to the upstream caused by throttling are well solved while reducing the pressure and increasing the speed. This ensures that the flow rate, flow velocity and pressure of the refrigerant in each branch pipe 2 can meet the working requirements of the heat exchanger, ensuring that the heat exchanger has excellent and stable heat exchange performance.

[0070] Although the present embodiment is described by taking the novel refrigerant distributor integrating reflection and mixing as an example, the present invention does not make any limitation to this. Similarly, the present embodiment does not make any limitation to the structure of the liquid inlet pipe 4.

[0071] Correspondingly, this embodiment further provides a heat exchanger assembly including the above-mentioned novel refrigerant distributor, and the heat exchanger assembly is an evaporator or a condenser.

[0072] On the other hand, this embodiment further provides a refrigeration device including the above-mentioned heat exchanger assembly, and the refrigeration device is other refrigeration equipment such as an air conditioner, a refrigeration and freezing device, and a heat pump water heater.

[0073] Example 2

[0074] This embodiment is basically the same as the first embodiment and its variations, except that the speed increasing section 22 is formed in a different manner. Figure 12 As shown, each branch pipe 2 further includes a branch section 23 welded to the downstream of the branch pipe connecting section 21 , and the speed increasing section 22 is formed on the branch section 23 .

[0075] Specifically, the branch section 23 has a connection portion 231 that is outer-mounted on the transition section 212 and has a flared structure. A speed-increasing section 22 with a gradually decreasing inner diameter is formed downstream of the connection portion 231. However, the present invention does not impose any restrictions on the assembly method of the branch section and the branch pipe connection section. In other embodiments, the transition section 212 can also be set to a flared structure (or a flared section can be formed after the transition section) to be outer-mounted and welded to the connection portion 231 on the branch section. The speed-increasing section 22 is still a structure with a gradually decreasing inner diameter located downstream of the connection portion 231, such as Figure 13 shown.

[0076] In this embodiment, the inner diameter d3 of the branch section 23 located downstream of the speed increasing section 22 is substantially close to the inner diameter d23 at the downstream end of the speed increasing section 22. However, the present invention is not limited thereto.

[0077] Although the present embodiment and the first embodiment are described with the speed increasing section 22 as a tapered structure, the present invention does not impose any limitation on this. Based on the control of the inner diameter difference Δd, the speed increasing section 22 can also be formed at the socket connection between the end of the branch pipe connecting section 21 and the branch section 23, that is, the speed increasing section is formed directly based on the inner diameter difference between the end of the branch pipe connecting section 21 and the branch section connecting portion 213, as shown in FIG. Figure 14 In this structure, no expansion or contraction processing is required on the branch pipe connecting section and the branch section connecting portion.

[0078] Although this embodiment and the first embodiment are both described by taking the example of the branch pipe 2 having only one speed increasing section, the present invention does not make any limitation to this. Figure 15 As shown, multiple speed-increasing sections 22' can be provided after the attenuation section 211. Based on these speed-increasing sections 22', the refrigerant is subjected to multi-stage pressure reduction and speed-increasing. Meanwhile, the inner diameter difference Δd' between adjacent speed-increasing sections is controlled to control the degree of throttling within each speed-increasing section, thereby minimizing pressure losses and downstream pressure wave oscillations caused by throttling and pressure reduction. Specifically, the inner diameter difference Δd' between adjacent speed-increasing sections refers to the difference between the inner diameter at the downstream end of each speed-increasing section and the inner diameter at the downstream end of the adjacent speed-increasing section.

[0079] The present invention does not impose any restrictions on the structure of the distributor body 1. Any distributor body that can improve the mixing degree of the two-phase flow refrigerant is within the scope of protection of the present invention. Based on the excellent mixing distributor body 1, combined with the branch pipe structure provided by the present invention, the overall distributor diversion performance can be improved, thereby achieving comprehensive improvements in heat exchanger performance. Figures 16 to 18 Shown is a schematic structural diagram of a novel refrigerant distributor provided by other embodiments of the present invention.

[0080] Figure 16 The new refrigerant distributor shown does not have a partition. Figure 17 The new refrigerant distributor shown has a distributor body of a socket-type structure. Figure 18 The distributor body of the novel refrigerant distributor shown is a reflective structure.

[0081] Example 3

[0082] This embodiment is basically the same as the second embodiment and its variations, except that the structure of the branch segment 23 is different, such as Figure 19 shown.

[0083] To ensure better compatibility with refrigeration system piping during assembly, in this embodiment, the inner diameter of the branch section 23 located downstream of the speed-increasing section 22 is larger than the inner diameter d2 at the downstream end of the speed-increasing section 22. At this time, the speed-increasing section 22 has a straight section 222 with a substantially constant inner diameter, and the end of the straight section 222 is the downstream end of the speed-increasing section 22. The straight section 222 provides a stable range for the refrigerant after the speed increase, preventing the branch section 23 located downstream of the speed-increasing section 22 and having a relatively large inner diameter from affecting the flow rate of the refrigerant, thereby ensuring a stable increase in the flow rate of the refrigerant. The present invention does not impose any restrictions on the length L1 of the straight section.

[0084] Example 4

[0085] This embodiment is basically the same as the first embodiment and its variations, with the difference being that the specific structure of the distributor body 1 and the bending direction of the attenuation section 211 are different.

[0086] In the first embodiment, the attenuation section 211 bends and extends in a direction away from the center line of the dispenser body 1; in this embodiment, Figure 20 As shown, the attenuation section 211 extends toward the centerline of the distributor body 1. Similarly, in this embodiment, the angle α formed by the intersection of the axis at the upstream end of the attenuation section and the axis at the downstream end of the attenuation section still satisfies the following: 90° ≤ α ≤ 175°. However, the present invention does not impose any restrictions on the curvature of the attenuation section. In the present invention, the attenuation section can extend in any direction relative to the centerline of the diverter hole in which it is located (i.e., a 360-degree curve).

[0087] Furthermore, in this embodiment, the centerline of the diverter hole 104 intersects the centerline of the distributor body 1, meaning that the diverter hole 104 is oblique relative to the centerline of the distributor body 1. Similarly, in this embodiment, along the refrigerant flow direction within the diverter branch pipe 2, the straight length L from the point where the attenuation section 211 begins to bend relative to the diverter hole centerline to the end face where the branch pipe connecting section 21 connects to the diverter hole 104 still satisfies the following conditions: 3mm≤L≤150mm.

[0088] In summary, in the new refrigerant distributor provided by the present invention, each branch pipe includes a branch pipe connecting section and an increasing speed section located downstream of the branch pipe connecting section. The branch pipe connecting section with a larger inner diameter increases the refrigerant flow rate distributed to each branch pipe and reduces the refrigerant distribution resistance; while the increasing speed section increases the refrigerant flow rate by reducing the flow channel cross section. On this basis, the degree of pressure reduction and acceleration of the refrigerant by the increasing speed section is accurately controlled by setting the inner diameter difference △d to avoid excessive fluid pressure loss due to excessive throttling, thereby achieving balanced control of flow rate, flow rate and pressure during refrigerant distribution. Furthermore, by setting an attenuation portion that bends and extends to one side relative to the center line of the diversion hole on the branch pipe connecting section, the increasing speed section is no longer coaxial with the center line of the diversion hole. When the pressure wave generated by the refrigerant's velocity and pressure changes in the speed-increasing section propagates upstream, a portion of the pressure wave is reflected and absorbed by the outer inner wall of the attenuation section, while the other portion bends at the attenuation section and rapidly decays after undergoing a conversion in propagation mode. This effectively addresses the issue of reduced refrigerant flow and velocity at the diverter hole caused by downstream pressure wave oscillations, effectively improving the diversion performance of the refrigerant distributor. Furthermore, to balance the refrigerant pressure loss caused by the bending of the attenuation section and the impact strength of the outer inner wall of the attenuation section, the axis at the upstream end of the attenuation section and the axis at the downstream end of the attenuation section intersect to form an angle α, with a value of 90°≤α≤175°.

[0089] Although the present invention has been disclosed above by means of preferred embodiments, this is not intended to limit the present invention. Anyone skilled in the art may make slight changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope of protection required by the claims.

Claims

1. A new type of refrigerant distributor, characterized in that: include: The distributor body includes a liquid inlet end and a liquid outlet end. The distributor body is formed with a distribution area located downstream of the liquid inlet end. The liquid outlet end of the distributor body is formed with a plurality of diversion holes communicating with the distribution area. A plurality of branch pipes are respectively welded and connected to the plurality of branch holes; Among them, each branch pipe includes at least one speed-increasing section whose inner diameter decreases along the flow direction of the refrigerant in the branch pipe and a branch pipe connecting section located upstream of the speed-increasing section, and the difference △d between the inner diameter d1 at the downstream end of the branch pipe connecting section and the inner diameter d2 at the downstream end of the speed-increasing section is: 0.1mm≤△d≤3.5mm; an attenuation section is formed on the branch pipe connecting section, which is bent and extended toward one side relative to the center line of the diversion hole, and the axis at the upstream end of the attenuation section and the axis at the downstream end of the attenuation section intersect to form an angle α and 90°≤α≤175°. Based on the attenuation section, the axis of the speed-increasing section intersects with the center line of the diversion hole.

2. The novel refrigerant distributor according to claim 1 is characterized in that: The branch pipe connecting section further includes a transition section located downstream of the attenuation section to connect to the speed-increasing section, and the transition section extends along the axial direction at the downstream end of the attenuation section.

3. The new refrigerant distributor according to claim 1 is characterized in that: Along the refrigerant flow direction in the branch pipe, the straight section length L from the point where the attenuation section begins to bend relative to the center line of the diversion hole to the end face where the branch pipe connecting section connects to the diversion hole is: 3mm≤L≤150mm.

4. The novel refrigerant distributor according to claim 1 is characterized in that: The speed increasing section is a tapered structure integrally formed with the branch pipe connecting section and having a gradually decreasing inner diameter; each branch pipe also includes a branch section, which is welded to the speed increasing section, or the branch pipe connecting section, the speed increasing section and the branch section are integrally formed.

5. The novel refrigerant distributor according to claim 1 is characterized in that: Each branch pipe further includes a branch section welded to the downstream of the branch pipe connecting section, and the speed increasing section is formed at the welding position of the branch section or formed on the branch section.

6. The novel refrigerant distributor according to claim 4 or 5, characterized in that: The inner diameter of the branch section located downstream of the speed-increasing section is substantially close to the inner diameter of the downstream end of the speed-increasing section; Alternatively, the inner diameter of the branch section downstream of the speed-increasing section is larger than the inner diameter at the downstream end of the speed-increasing section, and the speed-increasing section has a straight section with a substantially constant inner diameter.

7. The novel refrigerant distributor according to claim 5, characterized in that: The branch section is a straight pipe that gradually extends along the axis direction of the downstream end of the speed-increasing section; or, the branch section is a curved pipe that bends and extends to one side relative to the axis of the downstream end of the speed-increasing section.

8. The novel refrigerant distributor according to claim 1 is characterized in that: Each diversion hole includes a pipe hole section welded to the corresponding branch pipe connection section and a drainage hole section communicating with the pipe hole section and the distribution area. The inner diameter of the drainage hole section gradually decreases along the flow direction of the refrigerant.

9. The novel refrigerant distributor according to claim 1, characterized in that: A guide section whose inner diameter gradually decreases along the refrigerant inflow direction is formed on one end of the branch pipe connecting section connected to the diversion hole, and the inner wall generatrix of the guide section is an inclined straight line or an arc curve.

10. The novel refrigerant distributor according to claim 1, characterized in that: The axis of each diversion hole is substantially parallel to the axis of the distributor body.

11. A heat exchanger assembly, characterized in that: The invention comprises the novel refrigerant distributor as claimed in claim 1.

12. A refrigeration device, characterized in that: The heat exchanger assembly comprises the heat exchanger assembly according to claim 11.

Images