A plate heat exchanger

Abstract

The present invention is applicable to the field of heat exchanger technology and provides a plate heat exchanger comprising several heat exchange units. Each heat exchange unit comprises two first plates, each having flanges disposed on its edge. The flanges of the two first plates are interconnected to form a chamber. A second plate and a third plate are disposed between the two first plates. The second plate divides the chamber into a refrigerant flow channel and a coolant flow channel, and the third plate is disposed in the coolant flow channel. By employing a unique structure that breaks through and alters the structure of traditional plate heat exchangers, this plate heat exchanger can significantly reduce the flow resistance of the refrigerant and coolant, improve the heat exchange capacity, and ensure uniform fluid distribution within the channels.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat exchangers, and in particular relates to a plate heat exchanger. Background Art

[0002] Plate heat exchanger is a high-efficiency heat exchanger. In the refrigeration system, plate heat exchanger is widely used as evaporator and condenser. It is one of the core components of the refrigeration system and its performance has a great impact on the refrigeration system.

[0003] The working principle of a plate heat exchanger is to exchange heat through the channels between the plates. The working fluid flows through the narrow, tortuous channels formed between the two plates. Due to the corrugated shape and complex cross-sectional variations of the plates, the flow direction and velocity of the fluid constantly change, increasing fluid disturbance and heat transfer. Therefore, reducing the flow resistance of the refrigerant and coolant in a plate heat exchanger while maintaining heat transfer capacity is crucial for improving the operating efficiency and reducing the power consumption of the refrigeration system. Summary of the Invention

[0004] The purpose of the embodiments of the present invention is to provide a plate heat exchanger, aiming to solve the problems raised in the above background technology.

[0005] An embodiment of the present invention is implemented as follows: a plate heat exchanger includes a plurality of heat exchange units, wherein the heat exchange units include two first plates, the edges of the first plates are provided with flanges, and the flanges of the edges of the two first plates are connected to each other to form a chamber, a second plate and a third plate are provided between the two first plates, the second plate divides the interior of the chamber into a refrigerant flow channel and a coolant flow channel, and the third plate is provided in the coolant flow channel;

[0006] Two first inlets are symmetrically distributed at both ends of the middle portion of the first plate, the first inlets are formed by stamping and have flanges, and the stamping directions of the two first inlets are opposite, one of the first inlets serves as a refrigerant inlet, and the other first inlet serves as a coolant inlet, and four first outlets are symmetrically distributed at the four corners of the first plate, the first outlets are also formed by stamping and have flanges, and the stamping directions of the first outlets along the length direction of the first plate are opposite, while the stamping directions of the first outlets along the width direction of the first plate are the same, the two first outlets close to the refrigerant inlet side serve as coolant outlets, and the first outlet close to the coolant inlet side serves as a refrigerant outlet;

[0007] There are convex points distributed on the second plate, and the upper surface and lower surface of the convex points are composed of two semi-ellipses with different major axes and the same minor axes, and the semi-ellipse on the upper surface is smaller than the semi-ellipse on the lower surface, and the semi-ellipse with the shorter major axis is opposite to the refrigerant inlet. The second plate is opened with two second inlets by stamping along the middle part of its width direction, and the stamping directions of the two second inlets are opposite, and the edge of the second inlet is also provided with a flange. Four second outlets are symmetrically distributed at the four corners of the second plate, and the second outlets are also formed by stamping and form flanges. The two second outlets along the width direction of the second plate are in the same direction, and the two second outlets along the length direction of the second plate are in opposite directions. The flanges abutting each other between the second plate and the first plate are welded to form a channel for the input and output of coolant and refrigerant.

[0008] According to a further technical solution, the flanges of the two first plate edges are connected by welding, specifically, by brazing.

[0009] A further technical solution is that a refrigerant input pipe is installed at the refrigerant input port, a coolant input pipe is installed at the coolant input port, a coolant output pipe is installed at the coolant output port, and a refrigerant output pipe is installed at the refrigerant output port.

[0010] According to a further technical solution, the third plate is an inner fin type plate, two holes are symmetrically opened in the middle of the third plate along its width direction, and four holes are opened at the four corners of the third plate.

[0011] A plate heat exchanger provided in an embodiment of the present invention breaks through and changes the structure of a traditional plate heat exchanger by adopting a special structure, which can significantly reduce the flow resistance of the refrigerant and coolant, improve the heat exchange capacity of the heat exchanger, and ensure the uniformity of fluid distribution in the channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A schematic diagram of the assembly of a plate heat exchanger provided in an embodiment of the present invention;

[0013] Figure 2 A schematic structural diagram of a first plate in a plate heat exchanger provided in an embodiment of the present invention;

[0014] Figure 3 A schematic structural diagram of a second plate in a plate heat exchanger provided in an embodiment of the present invention;

[0015] Figure 4 A schematic structural diagram of a third plate in a plate heat exchanger provided in an embodiment of the present invention;

[0016] Figure 5A cross-sectional view along the width direction of a plate heat exchanger provided in an embodiment of the present invention;

[0017] Figure 6 A schematic diagram of the overall structure of a plate heat exchanger provided in an embodiment of the present invention;

[0018] Figure 7 A schematic structural diagram of the cooperation between a first plate, a second plate, and a third plate in a plate heat exchanger provided in an embodiment of the present invention;

[0019] Figure 8 A temperature distribution diagram of the refrigerant side of a plate heat exchanger provided in an embodiment of the present invention;

[0020] Figure 9 A temperature distribution diagram of the coolant side of a plate heat exchanger provided in an embodiment of the present invention;

[0021] Figure 10 A refrigerant side pressure distribution diagram of a plate heat exchanger provided in an embodiment of the present invention;

[0022] Figure 11 This is a pressure distribution diagram of the coolant side of a plate heat exchanger provided in an embodiment of the present invention.

[0023] In the accompanying drawings: 1-first plate; 2-second plate; 21-bump; 3-third plate; 4-refrigerant inlet pipe; 5-refrigerant outlet pipe; 6-cooling liquid inlet pipe; 7-cooling liquid outlet pipe. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0025] The specific implementation of the present invention is described in detail below with reference to specific embodiments.

[0026] like Figure 1-7 FIG. 1 shows a plate heat exchanger provided in accordance with an embodiment of the present invention, comprising a plurality of heat exchange units. The heat exchange units comprise two first plates 1, each of which has a flange at its edge. The flanges at the edges of the two first plates 1 are connected to form a chamber. A second plate 2 and a third plate 3 are provided between the two first plates 1. The second plate 2 divides the chamber into a refrigerant flow channel and a coolant flow channel. The third plate 3 is provided in the coolant flow channel.

[0027] Two first inlets are symmetrically distributed at both ends of the middle part of the first plate 1. The first inlets are formed by stamping and have flanges, and the stamping directions of the two first inlets are opposite. One of the first inlets serves as a refrigerant inlet, and the other first inlet serves as a coolant inlet. Four first outlets are symmetrically distributed at the four corners of the first plate 1. The first outlets are also formed by stamping and have flanges, and the stamping directions of the first outlets along the length direction of the first plate 1 are opposite, while the stamping directions of the first outlets along the width direction of the first plate 1 are the same. The two first outlets on the side close to the refrigerant inlet serve as coolant outlets, and the first outlet on the side close to the coolant inlet serves as a refrigerant outlet.

[0028] There are protrusions 21 distributed on the second plate 2, and the upper surface and lower surface of the protrusion 21 are composed of two semi-ellipses with different major axes and the same minor axes, and the semi-ellipse on the upper surface is smaller than the semi-ellipse on the lower surface, and the semi-ellipse with the shorter major axis is opposite to the refrigerant inlet. The second plate 2 is opened with two second inlets by stamping along the middle part of its width direction, and the stamping directions of the two second inlets are opposite, and the edge of the second inlet is also provided with a flange. There are four second outlets symmetrically distributed at the four corners of the second plate 2, and the second outlets are also formed by stamping and form flanges. The two second outlets along the width direction of the second plate 2 are in the same direction, and the two second outlets along the length direction of the second plate 2 are in opposite directions. The flanges abutting each other between the second plate 2 and the first plate 1 form a channel by welding for the input and output of coolant and refrigerant.

[0029] As a preferred embodiment of the present invention, the flanges of the edges of the two first plates 1 are connected by welding, specifically, by brazing.

[0030] As a preferred embodiment of the present invention, a refrigerant inlet pipe 4 is installed at the refrigerant inlet, a coolant inlet pipe 6 is installed at the coolant inlet, a coolant outlet pipe 7 is installed at the coolant outlet, and a refrigerant outlet pipe 5 is installed at the refrigerant outlet.

[0031] As a preferred embodiment of the present invention, the third plate 3 is an inner fin type plate, and the third plate 3 has two holes symmetrically opened in the middle along its width direction, and four holes are opened at the four corners of the third plate 3, each hole is used to match the channel between the second plate 2 and the first plate 1.

[0032] like Figure 7-10As shown, simulation analysis is introduced to further illustrate the effectiveness of this device. The heat exchanger used in the simulation is made of aluminum alloy, with 21 layers of refrigerant flow channels and 22 layers of coolant flow channels. R134a is used as the refrigerant and a 50% volume fraction of ethylene glycol aqueous solution is used as the coolant. To improve computational efficiency, the simulation assumes that the refrigerant and coolant are distributed equally between the flow channels, using one layer of refrigerant and one layer of coolant. The target heat exchange capacity of the simulation is 4500W, and the simulated operating conditions are shown in Table 1:

[0033] Table 1

[0034] Refrigerant valve front pressure MPa 1 Refrigerant valve front temperature ℃ 34.4 Refrigerant valve evaporation temperature ℃ -12.7 Refrigerant inlet mass flow kg / h 102.76 Antifreeze inlet temperature ℃ 5 Antifreeze inlet mass flow kg / h 649.2

[0035] The simulation results are shown in Table 2:

[0036] Table 2

[0037] Antifreeze outlet temperature ℃ -3.3 Refrigerant outlet temperature ℃ -7.2 Antifreeze side pressure drop kPa 2.2 Refrigerant side pressure drop kPa 0.4 Overall heat transfer W 4554

[0038] Figure 8 is the temperature distribution on the refrigerant side, Figure 9 The temperature distribution on the coolant side is that the refrigerant is evenly distributed during the flow process, there is an obvious overheating area at the outlet, the coolant temperature is evenly distributed, and the temperature distribution at different positions in the width direction is basically the same, and the overall heat exchange effect is good. Figure 10 is the pressure distribution on the refrigerant side, Figure 11 It is the pressure distribution on the coolant side. The pressure drops on both the refrigerant and coolant sides are evenly distributed and the pressure drops are small.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A plate heat exchanger, characterized in that: The heat exchange unit comprises a plurality of heat exchange units, each comprising two first plates, each of the first plates being provided with flanges at its edges, the flanges of the two first plates being connected to form a chamber, a second plate and a third plate being provided between the two first plates, the second plate dividing the chamber into a refrigerant flow channel and a coolant flow channel, and the third plate being provided in the coolant flow channel; Two first inlets are symmetrically distributed at both ends of the middle portion of the first plate, the first inlets are formed by stamping and have flanges, and the stamping directions of the two first inlets are opposite, one of the first inlets serves as a refrigerant inlet, and the other first inlet serves as a coolant inlet, and four first outlets are symmetrically distributed at the four corners of the first plate, the first outlets are also formed by stamping and have flanges, and the stamping directions of the first outlets along the length direction of the first plate are opposite, while the stamping directions of the first outlets along the width direction of the first plate are the same, the two first outlets close to the refrigerant inlet side serve as coolant outlets, and the first outlet close to the coolant inlet side serves as a refrigerant outlet; There are convex points distributed on the second plate, and the upper surface and lower surface of the convex points are composed of two semi-ellipses with different major axes and the same minor axes, and the semi-ellipse on the upper surface is smaller than the semi-ellipse on the lower surface, and the semi-ellipse with the shorter major axis is opposite to the refrigerant inlet. The second plate is opened with two second inlets by stamping along the middle part of its width direction, and the stamping directions of the two second inlets are opposite, and the edge of the second inlet is also provided with a flange. Four second outlets are symmetrically distributed at the four corners of the second plate, and the second outlets are also formed by stamping and form flanges. The two second outlets along the width direction of the second plate are in the same direction, and the two second outlets along the length direction of the second plate are in opposite directions. The flanges abutting each other between the second plate and the first plate are welded to form a channel for the input and output of coolant and refrigerant.

2. The plate heat exchanger according to claim 1, characterized in that The flanges of the two first plate edges are connected by welding.

3. The plate heat exchanger according to claim 1, characterized in that A refrigerant input pipe is installed at the refrigerant input port, a coolant input pipe is installed at the cooling liquid input port, a coolant output pipe is installed at the cooling liquid output port, and a refrigerant output pipe is installed at the refrigerant output port.

4. The plate heat exchanger according to claim 2, characterized in that The third plate is an inner fin type plate. Two holes are symmetrically opened in the middle of the third plate along the width direction, and four holes are opened at the four corners of the third plate.

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