A heat pump water-refrigerant antifreeze plate heat exchanger

Abstract

The present invention discloses a heat pump water-refrigerant antifreeze plate heat exchanger, wherein a heat exchange water flow channel and a heat exchange refrigerant flow channel are provided in the plate heat exchanger, and the heat exchange water flow channel and the heat exchange refrigerant flow channel are separated by a heat exchange plate, and a plurality of elastic spheres are provided in the heat exchange water flow channel, the spheres are hollow inside, and are connected to each other by connecting rods, the spheres are arranged in an offset manner up and down, and the connecting rods connect adjacent spheres in a transverse and longitudinal manner to form a mesh chain structure in the heat exchange water flow channel. In this embodiment, a sphere is provided in the heat exchange water flow channel, and a strong vortex can be generated when water flows through the sphere. Compared with the heat exchange water flow channel of a traditional plate heat exchanger, the vortex in the heat exchange water flow channel is more intense, and has a better heat exchange effect. The hollow sphere of the present invention can absorb the volume expanded by ice to prevent the plate heat exchanger from being frozen and damaged.

Description

Technical Field

[0001] The invention relates to a heat pump plate heat exchanger, in particular to an air source heat pump water-refrigerant antifreeze plate heat exchanger, and belongs to the technical field of HVAC heat pumps. Background Art

[0002] Plate heat exchangers are widely used in heat exchangers used in air energy heat pump systems due to their small size, high heat exchange efficiency, and corrosion resistance, in the form of water-refrigerant plate heat exchangers.

[0003] The water capacity of the plate heat exchanger is small, and the pressure of each flow channel is equal. When the water freezes in the flow channel, the volume expands, which can easily break the plate heat exchanger. External causes of freezing damage include: insufficient water flow, blockage of the refrigerant channel, uneven distribution of refrigerant, etc.; long-term power outages during the winter freezing period and the heat exchanger is installed outdoors with the host without being emptied can also easily cause freezing damage to the heat exchanger. After the plate heat exchanger is frozen, liquid water penetrates into the refrigerant system from the flow channel, which can cause the host to be scrapped in severe cases.

[0004] Therefore, the plate heat exchanger needs a structural improvement that can effectively avoid freezing damage while maintaining its own advantages. Summary of the invention

[0005] The purpose of the present invention is to overcome the above problems and provide a heat pump water-refrigerant antifreeze plate heat exchanger. To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A heat pump water-refrigerant antifreeze plate heat exchanger, wherein a heat exchange water flow channel and a heat exchange refrigerant flow channel are provided in the plate heat exchanger, wherein the heat exchange water flow channel and the heat exchange refrigerant flow channel are separated by a heat exchange plate, wherein a plurality of elastic spheres are provided in the heat exchange water flow channel, wherein the spheres are hollow inside and are connected to each other by connecting rods, wherein the spheres are arranged in an offset manner up and down, and the connecting rods connect adjacent spheres in a transverse and longitudinal manner, thereby forming a mesh chain structure in the heat exchange water flow channel.

[0007] As an improvement, the cumulative volume of the hollow part of the sphere is more than twice the volume expansion of the water in the water exchange water flow channel when it freezes into ice.

[0008] As an improvement, the mesh chain structure composed of the spheres and connecting rods is an integral structure made of the same material.

[0009] As an improvement, the mesh chain structure composed of the spheres and connecting rods is made of elastic polymer material.

[0010] As an improvement, the network chain structure adopts a one-time molding process.

[0011] As an improvement, the heat exchange water flow channel and the heat exchange cold medium flow channel are arranged crosswise, and a countercurrent heat exchange method is used.

[0012] The advantages of the present invention are:

[0013] 1. In this embodiment, a sphere is provided in the hot water flow channel. When water flows through the sphere, a strong vortex can be generated. Compared with the hot water flow channel of the traditional plate heat exchanger, the vortex in the hot water flow channel is more intense and has a better heat exchange effect.

[0014] 2. After the liquid water freezes in the hot water flow channel, the hollow part of the sphere absorbs the volume that overflows due to the expansion of ice, thereby alleviating the damage to the heat exchanger plates caused by the squeezing force of ice expansion. This active anti-freezing method ensures that the plate heat exchanger will not be damaged by freezing even in an iced state. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a structural diagram of a heat pump water-refrigerant antifreeze plate heat exchanger network chain structure in Example 1;

[0016] Figure 2 A cross-sectional view of a heat pump water-refrigerant antifreeze plate heat exchanger at position aa in Example 1;

[0017] Figure 3 This is a structural diagram of a heat pump water-refrigerant antifreeze type plate heat exchanger in Example 1;

[0018] Figure 4 It is an enlarged view of the heat pump water-refrigerant antifreeze type plate heat exchanger at position Ⅰ in Example 1;

[0019] Figure 5 This is a state diagram of a heat pump water-refrigerant antifreeze plate heat exchanger before freezing at position Ⅰ in Example 1;

[0020] Figure 6 This is a state diagram of a heat pump water-refrigerant antifreeze plate heat exchanger after freezing at location Ⅰ in Example 1.

[0021] The symbols in the figure are:

[0022] 1-sphere, 101-hollow part of the sphere, 102-mesh chain structure, 103-hollow part of the mesh chain structure, 2-connecting rod, 3-heat exchange plate, A-heat exchange water flow channel, B-heat exchange refrigerant flow channel, A01-water in the heat exchange water flow channel before freezing; A02-ice layer in the frozen water flow channel, C-normal state of the sphere before freezing, D-deformed state of the sphere bag after freezing; F-expansion pressure of water freezing.

[0023] h1-the thickness of the sphere at its widest point, h-the minimum width between the heat exchange plates on both sides of the heat exchange water flow channel, and h2-the gap between the widest point of the sphere and the heat exchange plates. DETAILED DESCRIPTION

[0024] The present invention is described in detail and specifically by specific examples below to provide a better understanding of the present invention, but the following examples do not limit the protection scope of the present invention.

[0025] Example 1

[0026] This embodiment discloses a heat pump water-refrigerant antifreeze plate heat exchanger, in which a heat exchange water flow channel A and a heat exchange refrigerant flow channel B are provided. The heat exchange water flow channel A and the heat exchange refrigerant flow channel B are separated by a heat exchange plate 3 and arranged crosswise. A plurality of elastic spheres 1 are provided in the heat exchange water flow channel A, the spheres 1 are hollow inside, and are connected to each other by connecting rods 2, the spheres 1 are arranged in an up-and-down staggered manner, and the connecting rods 2 connect adjacent spheres 1 in a transverse and longitudinal manner, and form a mesh chain structure 102 in the heat exchange water flow channel A.

[0027] The cumulative volume of the hollow part 101 of the sphere is more than twice the volume expansion of the water in the heat exchange water flow channel A when it freezes.

[0028] The mesh chain structure 102 composed of the spheres 1 and the connecting rods 2 is an integral structure of the same material, which is a highly elastic polymer material and is formed in one step by processes such as extrusion and injection molding.

[0029] In this embodiment, the outer diameter of the sphere 1 is 5-7 mm, the center distance between the spheres 1 is 150 mm in the horizontal direction, and the center distance in the vertical direction is 50-60 mm. The thickness h1 at the widest part of the sphere 1 is less than the minimum width between the heat exchange plates 3 on both sides of the heat exchange water flow channel A, and h-h1 is kept larger than a gap of 1-2 mm, that is, a gap h2 of 0.5-1.0 mm is maintained between the widest part of the sphere 1 and the heat exchange plate 3.

[0030] like Figure 1 and Figure 3 As shown, the flow direction of water in the hot water flow channel A of the plate heat exchanger is opposite to the flow direction of the heat exchange refrigerant flow channel B, which is countercurrent heat exchange. In the hot water flow channel A, the layout of the spheres 1 on the mesh chain structure 102 is staggered and dense. When the water flows through the spheres 1 at high speed, it will be divided into two streams, and the direction of the water flow will be changed repeatedly, and it will be continuously flushed. Under the resistance of the mesh chain structure 102 and the spheres 1, the water flow forms a strong vortex, which is much more intense than the vortex in the flow channel without the elastic absorber antifreeze plate, which can effectively improve the heat exchange efficiency.

[0031] The spheres 1 maintain a certain distance from each other, and the hollow part 103 of the mesh chain structure ensures that the fluid can flow smoothly inside the hot water flow channel A, so as not to seriously affect the water's passing capacity; at the same time, due to the thickness of the sphere 1, when the hot water flow channel A is in liquid water, the thickest part of the hollow sphere 1 and the narrowest part of the heat exchange plate 3 only maintain a gap of about 1-2mm, and will not be displaced under the action of the water flow. When the hot water flow channel A is in liquid water, the sphere 1 is in the normal C state, and the sphere 1 does not undergo any deformation; during the freezing process or after freezing, due to the characteristic that the volume of water will expand and increase in the process of turning into ice crystals, the volume of water will increase by about 9% after it is completely frozen, and the force of 1 gram of water when it freezes is about 960kg / cm 2 Although the volume expansion of water is not large when it turns into ice, the squeezing force it generates is amazing. During the crystallization process of water, the material of the sphere 1 undergoes elastic deformation under the action of the ice squeezing force F, and the hollow part 101 of the sphere undergoes severe deformation, which completely offsets the increase in volume during the process of water forming ice crystals, forming a sphere wrapped in an ice deformation state D. Since the cumulative volume of the hollow part of the hollow sphere is more than twice the volume expansion of water in the heat exchange channel when it freezes, the overall area of ​​the elastic structure is equivalent to the effective heat exchange area of ​​the heat exchange plate 3, and the layout density of the sphere 1 is sufficient to ensure that the ice expansion force at any point in the hot water flow channel A can be absorbed, thereby ensuring that even if the entire hot water flow channel A is completely frozen, the heat exchange plate 3 of the plate heat exchanger will not be frozen back.

[0032] The specific embodiments of the present invention are described in detail above, but they are only examples, and the present invention is not equivalent to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions made to the present invention are also within the scope of the present invention. Therefore, the equalization changes and modifications made without departing from the spirit and scope of the present invention should be included in the scope of the present invention.

Claims

1. A heat pump water-refrigerant antifreeze plate heat exchanger, wherein a heat exchange water flow channel and a heat exchange refrigerant flow channel are provided in the plate heat exchanger, and the heat exchange water flow channel and the heat exchange refrigerant flow channel are separated by a heat exchange plate, characterized in that: A plurality of elastic spheres are arranged in the hot water exchange flow channel. The spheres are hollow inside and connected to each other through connecting rods. The spheres are arranged in an up-down staggered manner. The connecting rods connect adjacent spheres in a transverse and longitudinal manner to form a mesh chain structure in the hot water exchange flow channel. The cumulative volume of the hollow part of the sphere is more than twice the volume expansion of the water in the heat exchange water flow channel when it freezes into ice.

2. A heat pump water-refrigerant antifreeze plate heat exchanger according to claim 1, characterized in that: The mesh chain structure composed of the spheres and the connecting rods is an integral structure made of the same material.

3. A heat pump water-refrigerant antifreeze plate heat exchanger according to claim 2, characterized in that: The net chain structure composed of the spheres and the connecting rods is made of elastic polymer material.

4. A heat pump water-refrigerant antifreeze plate heat exchanger according to claim 2, characterized in that: The network chain structure adopts a one-time molding process.

5. The heat pump water-refrigerant antifreeze plate heat exchanger according to claim 1, characterized in that: The heat exchange hot water flow channel and the heat exchange cold medium flow channel are arranged in a cross pattern, and a countercurrent heat exchange method is adopted.

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