A liquid separator and its use

Abstract

The application belongs to the technical field of refrigeration equipment, and particularly relates to a distributor and application thereof. In the combination process of an acceleration hole plate and a distribution pipe, the single-hole opening of the acceleration hole plate is too large, resulting in poor gas-liquid mixing effect. The acceleration hole plate causes a large pressure drop. For a heat pump, throttling occurs after passing through the hole plate during heating, so that the liquid-phase refrigerant becomes gas-liquid two-phase refrigerant, thereby reducing the system performance. The application provides a distributor, which comprises a variable-diameter sleeve pipe. The variable-diameter sleeve pipe comprises a plurality of sub-sleeve pipes which are sequentially communicated. The diameters of the sub-sleeve pipes sequentially decrease. The largest-diameter sub-sleeve pipe, a connecting pipe and a liquid inlet pipe are sequentially communicated. A plurality of liquid outlet pipes are arranged on the sub-sleeve pipe and communicated with the sub-sleeve pipe. Uniform gas-liquid mixing is achieved, and the effect of uniform refrigerant distribution is achieved.

Description

Technical Field

[0001] The present application belongs to the technical field of refrigeration equipment, and in particular relates to a liquid separator and its application. Background Art

[0002] After passing through the expansion valve, some refrigerant flashes back into gas. Under the influence of gravity and the flash gas, the refrigerant-gas-liquid mixture flows toward areas with less resistance, resulting in uneven refrigerant distribution within each branch. Currently, the primary component used to ensure uniform refrigerant distribution within refrigeration systems is the liquid distributor, which consists of a distributor head and capillary tubes. Distributor heads are categorized as Venturi, pressure drop, centrifugal, and distribution tube types. Heat pumps primarily use Venturi and pressure drop distributor heads. The two-phase refrigerant is evenly mixed in the distributor head before being distributed to the capillary tubes and subsequently into the various processes within the heat exchanger.

[0003] The Venturi-type distributor head has a relatively smooth shape and does not cause turbulence. However, this can also lead to uneven distribution when flash gas is high. Other advantages include minimal pressure loss, a simple structure, and the lack of accessories. However, each distributor head model can only accommodate a specific flow rate, lacking flexibility. Furthermore, internal linear machining is difficult and expensive. A pressure drop distributor head creates turbulence, thereby achieving more uniform mixing and distribution of the gas and liquid refrigerant. Furthermore, the pressure drop distributor head consists of a spring retaining ring, an orifice plate, and a housing. Therefore, flow can be adjusted simply by replacing the orifice plate, making it easy to use and adjust, and the split structure is also simple to machine. However, the pressure drop distributor head increases flow rate by throttling, resulting in significant pressure drop losses. During heating in a heat pump system, this can cause the pure liquid refrigerant to become two-phase refrigerant, reducing system performance.

[0004] Existing liquid distributors require high installation precision. To avoid the effects of gravity on the distributor head and capillary tube, they are installed vertically whenever possible. However, in practice, installation consistency is poor, resulting in inconsistent liquid distribution. Furthermore, the limited model number of Venturi-type distributor heads results in high distributor costs, while pressure-drop distributor heads result in significant pressure drop losses, which can reduce system performance during heating in heat pump systems. To address this issue, a new distributor structure has been adopted. This eliminates the distributor head and capillary tube and consists solely of a distributor tube and outlet pipe. A structure within the distributor tube ensures uniform mixing of the gas-liquid refrigerant. The two-phase refrigerant then flows evenly into each outlet pipe, each corresponding to a specific process flow, achieving relatively uniform flow distribution across each process flow. However, in the integration of the accelerating orifice plate and the distributor tube, the single opening of the accelerating orifice plate is too large, resulting in poor gas-liquid mixing. The large pressure drop caused by the accelerating orifice plate can lead to throttling in heat pumps during heating, converting the liquid refrigerant into a two-phase gas-liquid refrigerant after passing through the orifice plate, reducing system performance. Summary of the Invention

[0005] 1. Technical problems to be solved

[0006] Due to the problem that during the integration of the accelerating orifice plate and the liquid separator, the single hole of the accelerating orifice plate is too large, resulting in poor gas-liquid mixing. The accelerating orifice plate causes a large pressure drop. For heat pumps, this can cause throttling after passing through the orifice plate during heating, turning the liquid refrigerant into a two-phase gas-liquid refrigerant, reducing system performance. This application provides a liquid separator and its application.

[0007] 2. Technical solution

[0008] In order to achieve the above-mentioned purpose, the present application provides a liquid distributor, including a reducing sleeve, which includes several sub-sleeves connected in sequence, the diameters of the sub-sleeves gradually decrease, the sub-sleeve with the largest diameter, the connecting pipe and the liquid inlet pipe are connected in sequence, and several liquid outlet pipes are provided on the sub-sleeve, which are connected to the sub-sleeves. The refrigerant flows from the sub-sleeve with the largest diameter to the sub-sleeve with the smallest diameter, and flows out through the liquid outlet pipes.

[0009] Another implementation manner provided by the present application is that: a plurality of the sub-casings have the same height; and each of the sub-casings is provided with the same number of the liquid outlet pipes.

[0010] Another embodiment provided by the present application is that the distance between the liquid outlet pipes on each of the sub-casings is different, and the distance gradually decreases along the flow direction.

[0011] Another embodiment provided by the present application is that a liquid outlet is provided on the sub-casing, and the liquid outlet pipe is connected with the sub-casing through the liquid outlet.

[0012] Another embodiment provided by the present application is that a filter is provided between the sub-casings, and the filter is provided between the connecting pipe and the sub-casing with the largest diameter.

[0013] Another implementation provided by the present application is: the filter opening area is At, and the sub-casing cross-sectional area is A, then the following condition is satisfied: 0.1≤At / A≤0.8.

[0014] Another embodiment provided by the present application is: the filter screen includes filter holes, the filter holes are circular, elliptical, square, triangular or trapezoidal, the filter hole diameter d is less than 0.5 mm, the center distance between the filter holes is D, D≥2d; the filter holes are evenly arranged in the filter screen, and the filter holes have variable diameter or equal diameter in the radial direction.

[0015] Another embodiment provided by the present application is that the filter screen includes a flow-guiding structure, and the flow-guiding structure is hemispherical, ellipsoidal or conical.

[0016] Another embodiment provided by the present application is that a plurality of partition components are provided on the filter screen.

[0017] The present application also provides an application of the liquid dispensing tube, wherein the liquid dispensing tube is applied to a heat exchanger or a heat pump.

[0018] 3. Beneficial effects

[0019] Compared with the prior art, the liquid dispenser provided in this application and its application have the following beneficial effects:

[0020] The liquid separator provided in the present application introduces a reducing sleeve and a filter as liquid separation elements to achieve uniform mixing of gas and liquid, thereby achieving the effect of uniform distribution of refrigerant.

[0021] The liquid separator provided in this application addresses the problem of uneven refrigerant distribution in each branch of the heat pump by introducing a reducing sleeve to achieve uniform refrigerant distribution in the corresponding outlet pipes in the upper and lower sleeves. Different filter types are designed to solve the problems of poor gas-liquid mixing in existing patents and reduced system performance caused by throttling during heating.

[0022] The liquid dispenser provided in this application uses a reducing sleeve for liquid separation, which reduces the number of liquid separation heads, reduces installation requirements, and improves the reliability of liquid separation. The use of a reducing sleeve structure can also reduce costs.

[0023] The liquid separator provided in this application uses a filter structure to achieve uniform gas-liquid distribution while causing little pressure drop, and can be used in heat pump systems BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the first structure of the liquid dispenser of the present application;

[0025] Figure 2 This is a second structural diagram of the liquid dispenser of the present application;

[0026] Figure 3 This is a third structural diagram of the liquid dispenser of the present application;

[0027] Figure 4 This is a schematic diagram of the first structure of the filter screen of this application;

[0028] Figure 5 This is a second structural diagram of the filter screen of the present application;

[0029] Figure 6 This is the third structural diagram of the filter screen of this application. DETAILED DESCRIPTION

[0030] Hereinafter, specific embodiments of the present application will be described in detail with reference to the accompanying drawings. Based on these detailed descriptions, those skilled in the art will be able to clearly understand the present application and implement the present application. Without violating the principles of the present application, the features of the various embodiments may be combined to obtain new implementations, or certain features of certain embodiments may be substituted to obtain other preferred implementations.

[0031] See also Figures 1 to 6 The present application provides a liquid distributor, including a reducing sleeve, which includes a plurality of sub-sleeves 12 connected in sequence, the diameters of the sub-sleeves 12 becoming smaller in sequence, the sub-sleeve 12 with the largest diameter, the connecting pipe 14 and the liquid inlet pipe 11 being connected in sequence, and a plurality of liquid outlet pipes 3 are provided on the sub-sleeve 12, the liquid outlet pipes 3 being connected with the sub-sleeve 12, and the refrigerant flows from the sub-sleeve 12 with the largest diameter to the sub-sleeve 12 with the smallest diameter, and flows out through the liquid outlet pipe 3.

[0032] The reducing sleeve 1 comprises a liquid inlet pipe 11 and a plurality of liquid outlet pipes 3 connected by sub-sleeves 12 .

[0033] Furthermore, several of the sub-casings 12 have the same height; each sub-casing 12 is provided with the same number of liquid outlet pipes 3, and the inner diameters of the sub-casings have a certain quantitative relationship. The reducing casing 1 contains multiple sub-casings 12, and each sub-casing 12 has the same height. The diameter of the tubes gradually decreases in a stepped manner along the refrigerant flow direction. This stepped decrease in diameter along the refrigerant flow direction serves to block some refrigerant from flowing upward, increasing the refrigerant flow rate within the casing 12 below the casing. At the same time, as the diameter decreases from one sub-casing 12 to another along the refrigerant flow direction, the refrigerant velocity increases.

[0034] The refrigerant has the same velocity distribution after entering each sub-tube 12. The reducer 1 is composed of n sub-tubes 12, and the diameter of each sub-tube 12 in the reducer 1 gradually decreases in a step-like manner along the refrigerant flow direction. There are n sub-tubes 12 along the flow direction, and each sub-tube 12 has the same number of liquid outlet pipes 3. The first sub-tube 12 that the refrigerant passes through has a diameter of D1 and a length of L1; the second sub-tube 12 that the refrigerant passes through has a diameter of D2 and a length of L2; the diameter of the xth sub-tube 12 that the refrigerant passes through is D x , length L x ...the uppermost sub-casing 12 diameter D n , length L n The total flow rate flowing into the reducer 1 is q m In an ideal state, the flow rate entering each liquid outlet pipe 3 is uniform, and the total flow rate flowing out of the liquid outlet pipe 3 contained in each sub-casing 12 is q=q m / n. The heights of the sub-casings 12 are equal, that is:

[0035] H1=H2=...=H n

[0036] The first sub-casing length of the refrigerant is H1(m); the second sub-casing length is H2(m); the xth sub-casing length is Hx(m) x (m)…The uppermost sub-casing length is H n (m).

[0037] The flow rate of the xth sub-casing q x is:

[0038]

[0039] The velocity of the xth sub-casing v x is:

[0040]

[0041] Wherein ρ is the refrigerant density kg / m 3 , q x is the flow rate of the xth sub-casing kg / s, A x is the cross-sectional area of the xth sub-casing m 2 , D x is the diameter of the xth sub-casing, n>x≥1.

[0042] Similarly, the flow rate of the (x+1)th sub-casing q x+1 is:

[0043]

[0044] The velocity of the (x+1)th sub-casing v x+1 is:

[0045]

[0046] In order to make the flow rate distribution of each sub-casing 12 corresponding to the distribution port uniform, the velocity of each sub-casing 12 is the same:

[0047] v x =v x+1

[0048] That is:

[0049]

[0050] The relationship between the xth sub-casing diameter D x and the (x+1)th sub-casing diameter D x+1 is:

[0051]

[0052] Further, the distance between the liquid outlet pipes 3 on each sub-casing 12 is different, and gradually decreases along the flow direction. The distribution of the liquid outlet pipes 3 on each sub-casing 12 is the same.

[0053] The distance between the liquid outlet pipes 3 in each sub-casing 12 is not equal, and the distance between the liquid distribution ports 13 in the sub-casing 12 increases along the flow direction of the refrigerant. The velocity of the refrigerant in the sub-casing 12 decreases along the flow direction, and the velocity and momentum of the refrigerant are larger at the lower part of the sub-casing 12, which can cause more refrigerant to rush to the upper part of the sub-casing 12, resulting in less flow at the outlet of the lower liquid outlet pipe 3 and more flow at the outlet of the upper liquid outlet pipe 3. Increasing the distance between the liquid outlet pipes 3 along the flow direction of the refrigerant in the sub-casing 12 is beneficial to reduce the flow unevenness between the liquid outlet pipes 3 caused by too large inlet momentum, and makes the flow distribution between the liquid outlet pipes 3 uniform.

[0054] Further, the sub-casing 12 is provided with a liquid outlet port 13, and the liquid outlet pipe 3 communicates with the sub-casing through the liquid outlet port 13.

[0055] Further, the filter screen 2 is arranged between the sub-casings 12, and the connecting pipe 14 is provided with the filter screen 2 between the sub-casing 12 with the largest diameter. There is one liquid inlet pipe 11 and a plurality of liquid outlet pipes 3 connected by the liquid outlet ports 13, which are spaced apart by the filter screen 2. The distance between the liquid outlet ports 13 can be equal or variable.

[0056] The filter screen 2 between the sub-casings 12 gradually decreases the opening area ratio along the flow direction of the refrigerant.

[0057] Further, the opening area of the filter screen 2 is At, and the cross-sectional area of the sub-casing 12 is A, which satisfies 0.1≤At / A≤0.8. The total opening area of the filter screen 2 is smaller than the opening area of the sub-casing 12 in order to accelerate the gas-liquid two-phase refrigerant after passing through the filter screen 2. The filter screen 2 plays a role in uniformly mixing and accelerating the gas-liquid two-phase refrigerant and dispersing the gas-liquid two-phase refrigerant. Accelerating the gas-liquid two-phase refrigerant enables the gas-liquid two-phase refrigerant to reach the top of the sub-casing 12, and dispersing the gas-liquid two-phase refrigerant enables the outlet flow between each liquid outlet port 13 corresponding to the sub-casing 12 to be equal.

[0058] Further, the filter screen 2 includes filter holes 21, which are circular, elliptical, square, triangular or trapezoidal, the diameter d of the filter holes 21 is less than 0.5 mm, the center distance D between the filter holes 21 is greater than or equal to 2d, the filter holes 21 are uniformly arranged in the filter screen 2, and the hole diameters of the filter holes 21 in the radial direction are variable or constant.

[0059] In order to make the gas-liquid two-phase refrigerant realize uniform mixing after passing through the filter hole 21, the diameter of the filter hole 21 is d < 0.5 mm. In order to ensure that the two-phase refrigerant passing through the filter screen 2 of each filter hole 21 is not mixed with each other after being rectified and dispersed, the center distance between the filter holes 21 is D, which needs to satisfy D ≥ 2d. The relationship between the distance between the filter holes 21 and the hole diameter needs to be greater than a certain value to ensure that the boundaries of each filter hole 21 do not interfere with each other, that is, the two-phase refrigerant flowing out of each filter hole 21 will not quickly merge. When the gas-liquid two-phase refrigerant entering the variable-diameter sleeve pipe 1 forms a bubble flow or a mist flow, the gas-liquid two-phase refrigerant is relatively uniformly distributed. The filter screen 2 is as shown in Figure 4 , the filter holes 21 are uniformly arranged in the entire filter screen 2, and the hole diameters of the filter holes 21 in the radial direction present a variable-diameter or equal-diameter relationship. The filter screen 2 plays a role of gas-liquid mixing, dispersion and acceleration.

[0060] Further, the filter screen 2 comprises a flow guide structure 22, which is a semi-spherical type, an ellipsoidal type or a conical type.

[0061] When the gas-liquid two-phase refrigerant entering the variable-diameter sleeve pipe forms a ring flow, the gas phase refrigerant is distributed in the middle of the variable-diameter sleeve pipe to form a gas core, and the liquid refrigerant is distributed near the wall of the variable-diameter sleeve pipe to form a liquid film. The filter screen 2 is as shown in Figure 5 , the filter holes 21 are opened near the wall of the filter screen 2, and the flow guide structure 22 is added to the solid part in the middle of the filter screen 2. The flow guide structure 22 guides the gas core to the wall near the liquid film, and then the gas-liquid mixture passes through the filter hole 21 to be rectified and dispersed to form a gas-liquid uniformly mixed two-phase mixture.

[0062] Further, the filter screen 2 is provided with a plurality of separation components 23. The separation components 23 can be connected with the flow guide structure 22 or can be arranged at intervals. When the gas-liquid two-phase refrigerant entering the variable-diameter sleeve pipe forms a slug flow or a plug flow, the gas phase refrigerant will converge to form a large bubble in the middle of the variable-diameter sleeve pipe. The filter screen 2 is as shown in Figure 6 , the filter holes 21 are opened around the filter screen 2, the flow guide structure 22 is added to the solid part in the middle of the filter screen 2, and a ring of uniformly distributed separation components 23 is matched around the flow guide structure 22. The shape of the flow guide structure 22 can be a semi-spherical type, an ellipsoidal type or a conical type, and the cross-sectional area of the flow guide structure 22 can be adjusted as needed, which is smaller than the area surrounded by the innermost ring of filter holes. The shape of the separation component 23 can be a vertical plate or a gradually changing circular tube. The flow guide structure 22 and the separation component 23 can be arranged in contact or at intervals. The flow guide structure 22 guides the large bubble in the middle to the wall near the variable-diameter sleeve pipe, and the separation component 23 uniformly divides the gas phase refrigerant guided by the flow guide structure 22 to the circumference to mix with the liquid phase refrigerant. The mixed gas-liquid two-phase refrigerant passes through the filter hole to be dispersed to form a gas-liquid uniformly mixed two-phase refrigerant. Here, the flow guide structure 22 can be in the form of a convex hull.

[0063] The present application also provides an application of the liquid dispensing tube, wherein the liquid dispensing tube is applied to a heat exchanger or a heat pump.

[0064] Using the heat exchanger of the embodiment of the present invention, the liquid outlet is evenly divided into multiple parts based on the sub-tube 12 by using a reducing sleeve as a liquid outlet pipe. The diameter of the sub-tube 12 gradually decreases along the flow direction of the refrigerant, which plays a role in accelerating the refrigerant and preventing the refrigerant from flowing too much into the upper sub-tube 12. By controlling the quantitative relationship of the diameters of the sub-tube 12, the purpose of uniform total flow rate outflowing from the outlet of each sub-tube 12 is achieved. The refrigerant after throttling by the expansion valve is a gas-liquid two-phase refrigerant. By adding a filter 2 at the inlet of the sub-tube 12 according to the flow pattern of the gas-liquid two-phase refrigerant, the gas-liquid two-phase is evenly mixed and then dispersed, so that the two-phase refrigerant entering each liquid outlet in the sub-tube is uniform, thereby achieving a uniform distribution of the flow rate of each flow path and maximizing the heat exchange capacity of the heat exchanger. Using a reducing sleeve and a filter 2 as a liquid outlet element instead of the original liquid outlet head and liquid outlet pipe can make the liquid outlet structure simpler and more reliable, and can also be more effective in cost control and liquid outlet effect assurance.

[0065] Using the heat pump of the embodiment of the present application, the liquid outlet is evenly divided into multiple parts with the sub-tube 12 as the unit by using a reducing sleeve as a liquid outlet pipe. The diameter of the sub-tube 12 gradually decreases along the flow direction of the refrigerant, which plays a role in accelerating the refrigerant and preventing the refrigerant from flowing too much into the upper sub-tube 12. By controlling the quantitative relationship of the diameters of the sub-tube 12, the purpose of uniform total flow rate outflowing from the outlet of each sub-tube 12 is achieved. The refrigerant after throttling by the expansion valve is a gas-liquid two-phase refrigerant. By adding a filter 2 at the inlet of the sub-tube 12 according to the flow pattern of the gas-liquid two-phase refrigerant, the gas-liquid two-phase is evenly mixed and then dispersed, so that the two-phase refrigerant entering each liquid outlet in the sub-tube 12 is uniform, thereby achieving a uniform distribution of the flow rate of each flow path and maximizing the heat exchange capacity of the heat exchanger. Using a reducing sleeve and a filter as a liquid outlet element instead of the original liquid outlet head and liquid outlet pipe can make the liquid outlet structure simpler and more reliable, and can also be more effective in cost control and liquid outlet effect assurance.

[0066] Although the present application has been described above with reference to specific embodiments, it should be understood by those skilled in the art that many modifications may be made to the configurations and details disclosed herein within the principles and scope of the present application. The scope of protection of the present application is determined by the appended claims, and the claims are intended to cover all modifications encompassed by the literal meaning or scope of equivalents of the technical features in the claims.

Claims

1. A liquid dispenser, characterized in that: The reducing sleeve comprises n sub-sleeves connected in sequence, wherein the diameters of the sub-sleeves decrease in sequence, the sub-sleeve with the largest diameter, the connecting pipe and the liquid inlet pipe are connected in sequence, and a plurality of liquid outlet pipes are provided on the sub-sleeves, which are connected to the sub-sleeves, and the refrigerant flows from the sub-sleeve with the largest diameter to the sub-sleeve with the smallest diameter and flows out through the liquid outlet pipes; the n sub-sleeves have the same height; the diameter of the x-th sub-sleeve is D x and (x+1) root casing diameter D x+1 The relationship between them is: Where n>x≥1; The multiple liquid outlet pipes on each sub-casing have the same size but different distances between them, and the distance gradually decreases along the flow direction; A filter is provided between the sub-tubes, and the filter is provided between the connecting pipe and the sub-tube with the largest diameter; the filter has an opening area ratio that gradually decreases along the refrigerant flow direction.

2. The liquid dispenser according to claim 1, wherein: Each sub-casing is provided with the same number of liquid outlet pipes.

3. The liquid dispenser according to claim 1, wherein: The sub-casing is provided with a liquid outlet, and the liquid outlet pipe is communicated with the sub-casing through the liquid outlet.

4. The liquid dispenser according to claim 1, wherein: The filter opening area is At, and the sub-casing cross-sectional area is A, then the following condition is satisfied: 0.1≤At / A≤0.

8.

5. The liquid dispenser according to claim 1, wherein: The filter screen includes filter holes, which are circular, elliptical, square, triangular or trapezoidal. The diameter of the filter holes d is less than 0.5 mm, and the center distance between the filter holes is D, D≥2d; the filter holes are evenly arranged in the filter screen, and the diameter of the filter holes is variable or constant in the radial direction.

6. The liquid dispenser according to claim 4, wherein: The filter screen includes a flow guiding structure, which is hemispherical, ellipsoidal or conical.

7. The liquid dispenser according to claim 6, wherein: The filter screen is provided with a plurality of partition components.

8. An application of the liquid dispenser according to any one of claims 1 to 7, characterized in that: The liquid separator is applied to a heat exchanger or a heat pump.

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