Flow tube length classified control V-shaped condenser

Abstract

The utility model relates to a V-shaped condenser with flow tube length classified control, which is a top air outlet V-shaped condenser, a refrigerant pipeline is divided into a plurality of paths which are connected in parallel for heat exchange, each path is distributed from top to bottom, the distance between each path and a top fan is gradually increased, the total length of a flow path is from long to short, and the tube diameter of a connecting tube between a flow path outlet and a condenser gathering tube is from large to small. According to the V-shaped condenser with the flow pipe length controlled in the classified mode, the heat exchange capacity of a pipeline is improved, the flow resistance is reduced, and the heat exchange efficiency is improved.

Description

Technical Field

[0001] The utility model belongs to the field of condensers, in particular to a V-shaped condenser with classified control of flow tube length. Background Technique

[0002] The condenser is one of the key components of the refrigeration system, which discharges the heat extracted from the refrigeration object and the energy driving the refrigeration system into the environment together. Therefore, the heat transfer efficiency of the condenser affects the energy conversion ability of the refrigeration system, that is, the level of energy efficiency. Refrigeration air conditioners, cold chain systems, heat pump technologies, etc. are important fields of current energy consumption and carbon emissions. Improving the heat transfer efficiency of the condenser has also become a key technology for energy conservation and carbon reduction. The top-outlet V-shaped condenser is a common form, which can provide a large heat transfer capacity with a small floor area and can be placed side by side for large-scale installation. However, there are differences in the angle and distance between the internal fan and the condenser coil of the top-outlet V-shaped condenser, and there are large differences in the air flow velocity and flow rate at the heat exchange tubes in different positions, and the heat exchange conditions are completely different. However, the existing V-shaped condensers adopt uniform tube layout and uniform liquid distribution of the refrigerant, resulting in insufficient heat transfer capacity of the pipelines with poor heat exchange conditions, large flow resistance, and low heat transfer efficiency. Therefore, it is extremely necessary to innovate and improve it. Summary of the Invention

[0003] In order to overcome the deficiencies of the existing V-shaped condenser with uniform tube layout, such as insufficient heat transfer capacity of the pipeline, large flow resistance, and low heat transfer efficiency, the utility model provides a V-shaped condenser with classified control of flow tube length, which improves the heat transfer capacity of the pipeline, reduces the flow resistance, and improves the heat transfer efficiency.

[0004] The technical solution adopted by the utility model to solve its technical problems is:

[0005] A V-shaped condenser with classified control of flow tube length, the V-shaped condenser is a top-outlet V-shaped condenser, the refrigerant pipeline is divided into multiple parallel heat exchange paths, each path is distributed from top to bottom, the distance from the top fan gradually increases, the total length of the flow path decreases from long to short, and the diameter of the connecting pipe between the flow path outlet and the condenser collecting pipe decreases from large to small.

[0006] Furthermore, the upper region of the heat exchange flow path close to the fan is allocated a large refrigerant flow rate, contains a large number of heat exchange tubes, and has a long total length of the flow path; the lower region of the heat exchange flow path far from the fan is allocated a small refrigerant flow rate, contains a small number of heat exchange tubes, and has a short total length of the flow path.

[0007] Furthermore, the base number of the heat exchange tubes is N1, the base number of the total flow path length is N2, and the base number of the refrigerant mass flow rate is N3. The refrigerant pipeline is divided into three parallel heat exchange paths, namely the upper region, the middle region, and the lower region. The number of heat exchange tubes, the total flow path length, and the refrigerant mass flow rate in different regions are k1N1, k2N2, and k3N3 respectively. For the flow path in the upper region, k1, k2, and k3 are all set to 1, and a large-diameter pipe is used for the connecting pipe between the flow path outlet and the condenser collecting pipe to reduce the flow resistance; for the flow path in the middle region, the value ranges of k1 and k2 are both 0.85 - 0.95, and the value range of k3 is 0.8 - 0.9, and a medium-diameter pipe is used for the connecting pipe between the flow path outlet and the condenser collecting pipe; for the flow path in the lower region, the value ranges of k1 and k2 are both 0.75 - 0.85, and the value range of k3 is 0.7 - 0.8, and a small-diameter pipe is used for the connecting pipe between the flow path outlet and the condenser collecting pipe to increase the resistance and reduce the refrigerant flow rate passing through the flow path. The above-mentioned regional division from top to bottom can be three grades, or two grades, or four grades, or other numbers of grades.

[0008] Preferably, the value range of N2 is set to 16 - 28 m, and N3 is determined by the following formula:

[0009] N3 = 3.1k4 / r

[0010] k4 is a correction coefficient, determined by the following formula, and r is the latent heat of vaporization of the refrigerant, with the unit kJ / kg

[0011] k4 = aA 2 +bA + c

[0012] a, b, and c are coefficients respectively, and the values adopted are -4.301e - 05, 0.02127, and -0.3544 respectively. A is the equivalent cross-sectional area of the heat exchange tube, determined by the following formula

[0013] A = 3.14*D 2 / 4

[0014] D is the outer diameter of the heat exchange tube.

[0015] The beneficial effects of the present utility model are mainly manifested in: improving the flow path length distribution and refrigerant flow rate distribution of the V-type condenser, making it match the air flow rate and velocity. In the region with a large air flow rate, the refrigerant flow rate is also large, and the pipeline is lengthened, and vice versa, thereby improving the overall heat exchange performance. Brief Description of the Drawings

[0016] Figure 1 It is an external schematic diagram of a V-type condenser with classified control of the flow tube length. 1. Heat exchange tube, 2. Fan.

[0017] Figure 2It is a schematic diagram of the pipeline of a V-type condenser with classified control of the flow tube length. 1. Heat exchange tube, 2. Fan, 3. Upper region flow path, 4. Large-diameter connecting pipe, 5. Summarizing pipe, 6. Middle region flow path, 7. Medium-diameter connecting pipe, 8. Small-diameter connecting pipe, 9. Lower region flow path. Detailed implementation mode

[0018] The present utility model will be further described below with reference to the accompanying drawings.

[0019] Refer to Figure 1 and Figure 2 , a V-type condenser with classified control of the flow tube length, the V-type condenser is a top-outlet V-type condenser, the refrigerant pipeline is divided into multiple parallel heat exchanges, each path is distributed from top to bottom, the distance from the top fan gradually increases, the total length of the flow path is from long to short, and the diameter of the connecting pipe between the flow path outlet and the condenser summarizing pipe decreases from large to small.

[0020] Further, the refrigerant flow rate distributed to the heat exchange flow path in the upper region close to the fan is large, the number of heat exchange tubes contained is large, and the total length of the flow path is long; the refrigerant flow rate distributed to the heat exchange flow path in the lower region far from the fan is small, the number of heat exchange tubes contained is small, and the total length of the flow path is short.

[0021] Still further, the base number of the heat exchange tubes is N1, the base number of the total length of the flow path is N2, and the base number of the refrigerant mass flow rate is N3. The refrigerant pipeline is divided into three parallel heat exchanges, namely the upper region, the middle region and the lower region. The number of heat exchange tubes, the total length of the flow path and the refrigerant mass flow rate in different regions are k1N1, k2N2, k3N3 respectively. For the flow path in the upper region, k1, k2, k3 are all set to 1, and a large-diameter pipe is used for the connecting pipe between the flow path outlet and the condenser summarizing pipe to reduce the flow resistance; for the flow path in the middle region, the value ranges of k1 and k2 are both 0.85 to 0.95, and the value range of k3 is 0.8 to 0.9, and a medium-diameter pipe is used for the connecting pipe between the flow path outlet and the condenser summarizing pipe; for the flow path in the lower region, the value ranges of k1 and k2 are both 0.75 to 0.85, and the value range of k3 is 0.7 to 0.8, and a small-diameter pipe is used for the connecting pipe between the flow path outlet and the condenser summarizing pipe to increase the resistance and reduce the refrigerant flow rate passing through the flow path. The above-mentioned regional division from top to bottom can be three gears, or two gears or four gears or other numbers of gears.

[0022] Preferably, the value range of N2 is set to 16 to 28 m, and N3 is determined by the following formula:

[0023] N3 = 3.1k4 / r

[0024] k4 is a correction coefficient, determined by the following formula, and r is the latent heat of vaporization of the refrigerant, with the unit kJ / kg

[0025] k4 = aA 2 + bA + c

[0026] a, b, and c are coefficients, with the values of -4.301e-05, 0.02127, and -0.3544 respectively. A is the equivalent cross-sectional area of the heat exchange tube, which is determined by the following formula

[0027] A = 3.14 * D 2 / 4

[0028] D is the outer diameter of the heat exchange tube.

[0029] Example: For a V-type condenser with heat exchange tubes having an outer diameter of 9.52 mm, using R404A refrigerant, the latent heat at a condensation temperature of 45 °C is 112.3 kJ / kg; in the flow path of the upper 1 / 3 region, each path is divided into 20 heat exchange tubes, with a total length of 18 m for each path, k4 = 0.94, the refrigerant mass flow rate is 0.026 kg / s, and the connecting pipe diameter between the flow path outlet and the condenser manifold is 9.52 mm; in the flow path of the middle 1 / 3 region, each path is divided into 18 heat exchange tubes, with a total length of 16.2 m for each path, the refrigerant mass flow rate is controlled at 0.022 kg / s, and the connecting pipe diameter is 6 mm; in the flow path of the lower 1 / 3 region, each path is divided into 16 heat exchange tubes, with a total length of 14.4 m for each path, the refrigerant mass flow rate is controlled at 0.019 kg / s, and the connecting pipe diameter is 3 mm.

[0030] In this embodiment, the air-side wind speed in the upper region is high, which not only enables good heat exchange and can condense more refrigerant, but also, since the refrigerant with a large gaseous volume quickly condenses into a refrigerant with a small liquid volume, the flow resistance is small, allowing for a larger refrigerant flow rate. Therefore, a larger refrigerant mass flow rate and flow path length can be permitted. On the contrary, in the lower region, a small refrigerant flow rate and a shorter total flow path length should be adopted.

[0031] The content described in the embodiments of this specification is only a listing of the implementation forms of the utility model concept and is only for illustrative purposes. The protection scope of the present utility model should not be regarded as being limited to the specific forms stated in this embodiment. The protection scope of the present utility model also extends to equivalent technical means that can be conceived by those of ordinary skill in the art based on the utility model concept.

Claims

1. A V-type condenser with classified control of flow tube length, characterized in that, The V-type condenser is a top-outlet V-type condenser. The refrigerant pipeline is divided into multiple parallel heat exchange paths, which are distributed from top to bottom, and the distance from each path to the top fan gradually increases. The total length of the flow path decreases from long to short, and the diameter of the connecting pipe between the flow path outlet and the condenser manifold decreases from large to small.

2. The V-type condenser with classified control of flow tube length according to claim 1, wherein In the upper area with a short distance from the fan, the refrigerant flow rate distributed to the heat exchange flow path is large, the number of heat exchange tubes it contains is large, and the total length of the flow path is long. In the lower area with a long distance from the fan, the refrigerant flow rate distributed to the heat exchange flow path is small, the number of heat exchange tubes it contains is small, and the total length of the flow path is short.

3. The V-type condenser with classified control of flow tube length according to claim 2, characterized in that, The base number of the number of heat exchange tubes is N1, the base number of the total length of the flow path is N2, and the base number of the refrigerant mass flow rate is N3. The refrigerant pipeline is divided into three parallel heat exchange paths, namely the upper area, the middle area, and the lower area. The number of heat exchange tubes, the total length of the flow path, and the refrigerant mass flow rate in different areas are k1N1, k2N2, and k3N3 respectively; for the flow path in the upper area, k1, k2, and k3 are all set to 1, and a large-diameter connecting pipe is used between the flow path outlet and the condenser manifold to reduce the flow resistance; for the flow path in the middle area, the value ranges of k1 and k2 are both 0.85 - 0.95, and the value range of k3 is 0.8 - 0.9, and a medium-diameter connecting pipe is used between the flow path outlet and the condenser manifold; for the flow path in the lower area, the value ranges of k1 and k2 are both 0.75 - 0.85, and the value range of k3 is 0.7 - 0.8, and a small-diameter connecting pipe is used between the flow path outlet and the condenser manifold to increase the resistance and reduce the refrigerant flow rate passing through the flow path.

4. The V-type condenser with classified control of flow tube length according to claim 3, characterized in that, The value range of N2 is set to 16 - 28m, and N3 is determined by the following formula: N3 = 3.1k4 / r k4 is a correction factor, determined by the following formula, and r is the latent heat of vaporization of the refrigerant, with the unit kJ / kg k4 = aA 2 + bA + c a, b, c are coefficients, and the values used are -4.301e - 05, 0.02127, -0.3544 respectively. A is the equivalent cross-sectional area of the heat exchange tube, determined by the following formula A = 3.14 * D 2 / 4 D is the outer diameter of the heat exchange tube.

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