KR20020048366A - Fin tube type heat exchanger and airconditioner and refrigerator using the heat exchanger - Google Patents

Abstract

PURPOSE: A fin tube type heat exchanger and air conditioner and freezer using the same are provided to save power while maintaining cooling performance. CONSTITUTION: A heat exchanger includes a tube(2) having a plurality of inner fins(5) on an inner circumferential surface thereof and a plurality of outer fins(10) on a periphery thereof. The inner fin is spirally extended from a central axis of the tube to the inner circumferential surface of the tube. Fine fins(7) protrude on surfaces of the inner fins hemispherically. The outer fins are made of annular thin plates. The outer fin has protrusions(11) and concavities(12) formed in radial direction of the tube to form a wave.

Description

Fin tube type heat exchanger and air conditioner and freezer using same {FIN TUBE TYPE HEAT EXCHANGER AND AIRCONDITIONER AND REFRIGERATOR USING THE HEAT EXCHANGER}

The demand for air conditioners is increasing day by day as the demand for comfortable living increases with the increase of income level.

Conventional air conditioners were developed several decades ago and there was not much improvement in the cooling efficiency of air conditioners except for the development of electronic control devices. To increase the efficiency of air conditioners, the performance of compressors, condensers and evaporators must be improved. Compressors have been significantly improved in efficiency, but there is still room for improvement in increasing the efficiency of condensers and evaporators.

9 is a perspective view showing a conventional plate heat exchanger. As shown in FIG. 9, a conventional air conditioner used a condenser and an evaporator made of a heat exchanger using a continuous plate fin tube in which a thin aluminum fin 101 was drilled and fitted with a copper tube 102. In this heat exchanger, since the aluminum fin 101 and the copper tube 102 are not completely bonded, the heat resistance is very large when heat is transferred between the copper tube 102 and the aluminum fin 101. Experimental data show that this heat resistance accounts for 18% to 33% of the total heat resistance. In order to overcome this problem, the aluminum fins 101 and the aluminum fins 101 have a small distance between them, and many aluminum fins 101 are installed in the tube, but the effect is insignificant.

In order to reduce the power consumption of the air conditioner to increase the cooling efficiency, to do this must reduce the amount of work to be done by the compressor and to increase the cooling efficiency per kg of refrigerant. To reduce the work of the compressor, the ratio between the discharge and suction pressures is reduced. However, when this ratio is lowered, the saturation pressure in the condenser is lowered, and thus the saturation temperature is lowered, and thus the difference in saturation temperature and air becomes smaller, which makes it difficult to fully condense the refrigerant. The amount of work to be done cannot be reduced, and thus power consumption cannot be reduced.

The present invention has been made to solve the above problems, an object of the present invention is to form an internal fin on the inner diameter surface of the tube to divide the inside into a plurality of channels, the fine fins on both sides of the inner fin to increase the heat transfer coefficient The outer diameter surface of the tube to form a corrugated outer fin along the circumferential angle to provide a heat exchanger with improved heat transfer capacity, by providing an air conditioner and a refrigerator including the heat exchanger, while having the same cooling capacity, the power is remarkable I want to save a lot.

An object of the present invention as described above, in the heat exchanger, a fin tube type heat exchange, characterized in that it comprises a tube (2) formed with a plurality of inner fins 5 on the inner diameter surface and a plurality of outer fins 10 on the outer diameter surface. It can be achieved by the group.

In addition, in order to achieve the object of the present invention, the inner pin (5) is preferably formed extending radially from the center axis line of the tube (2) to the inner diameter surface of the tube (2).

In addition, in order to achieve the object of the present invention, the inner pin (5) is preferably formed spirally along the central axis of the tube (2).

In addition, in order to achieve the object of the present invention, each of the inner pins 5 is preferably formed with a plurality of fine pins 7 protruding in the hemispherical surface.

In addition, in order to achieve the object of the present invention, the outer pin 10 is preferably made of an annular thin plate having a predetermined height along the outer diameter surface of the tube (2).

In addition, in order to achieve the object of the present invention, the outer fin 10 is preferably formed in the circumferential direction of the tube 2 and the protrusion 11 and the settled portion 12 alternately to form a wave shape.

In addition, in order to achieve the object of the present invention, the outer pin 10 is preferably increased as the distance between each adjacent protrusion 11 and the settled portion 12 in the radial direction.

In addition, in order to achieve the object of the present invention, it is preferable that the outer fin 10 is formed in an angle of 60 to 120 degrees with the outer diameter surface of the tube (2).

In addition, an object of the present invention, the inner tube 15 having a plurality of inner pins 5 on the inner diameter surface; And an outer tube 14 in which a plurality of outer fins 10 are formed on the outer diameter surface and the inner tube 15 is press-fitted to the inner diameter surface.

In addition, an object of the present invention, in the air conditioner, characterized in that it comprises a heat exchanger consisting of a tube (2) having a plurality of inner fins 5 on the inner diameter surface and a plurality of outer fins 10 on the outer diameter surface. 30; And an evaporator 40 comprising a heat exchanger consisting of a plurality of inner fins 5 on the inner diameter surface and a tube 2 having a plurality of outer fins 10 formed on the outer diameter surface. It can also be achieved by

In addition, in order to achieve the object of the present invention, the condenser 30 is preferably a plurality of the tube 2 is arranged in a square or cylindrical.

In addition, in order to achieve the object of the present invention, the evaporator 40, the inlet manifold 42 connected to each of the plurality of tubes (2) arranged on one side of the evaporator (40); A discharge manifold (41) connected to each of the plurality of tubes (2) arranged on the other side of the evaporator (40); And a U-tube 36 joining the end of each of the tubes 2 to interconnect each of the plurality of tubes 2 arranged in one row with the tubes 2 in adjacent rows.

In addition, in order to achieve the object of the present invention, it is preferable that the condenser 30 or the evaporator 40 is formed by standing the tube 2 vertically.

In addition, an object of the present invention is a refrigerator, characterized in that the refrigerator comprises a heat exchanger consisting of a tube (2) formed with a plurality of inner fins 5 on the inner diameter surface and a plurality of outer fins 10 on the outer diameter surface. It can also be achieved by

Other objects, specific advantages and novel features of the invention will become more apparent from the following detailed description and the preferred embodiments associated with the accompanying drawings.

1 is a front view showing a first embodiment of a fin tube type heat exchanger according to the present invention;

2 is a partial cross-sectional view showing a first embodiment of a fin tube type heat exchanger according to the present invention;

Figure 3 is a side view showing a part of the inner fin of the first embodiment of the fin tube type heat exchanger according to the present invention,

Figure 4 is a side view showing a first embodiment of a fin tube type heat exchanger according to the present invention,

5 is a front view showing a second embodiment of a fin tube type heat exchanger according to the present invention;

6 is a perspective view showing a condenser of an air conditioner according to the present invention;

6A is an enlarged view of a portion A of FIG. 6;

7 is a perspective view showing an evaporator of an air conditioner according to the present invention;

7A is an enlarged view of a portion B of FIG. 7;

8 is a left side view showing an evaporator of an air conditioner according to the present invention;

9 is a perspective view showing a conventional plate heat exchanger.

Explanation of the Main References

2: Tube 4: Subchannel

5: internal pin 7: fine pin

10: external pin 30: condenser

40: Evaporator

Hereinafter, a configuration of a fin tube type heat exchanger will be described with reference to the accompanying drawings.

1 is a front view showing a first embodiment of the fin tube type heat exchanger according to the present invention, Figure 2 is a partial sectional view showing a first embodiment of the fin tube type heat exchanger according to the present invention. As shown in FIGS. 1 and 2, five inner fins 5 are radially formed inside the tube 2 from the center axis of the tube 2 to the inner diameter surface of the tube 2. . The inner space of the tube 2 is divided into five subchannels 4 by the inner pins 5.

Each of the inner fins 5 has a hemispherical microfin 7 having a radius of about 0.4 mm on both sides of the inner fins 5 to increase the heat transfer area.

The outer fin 10 is an annular thin plate having a height of about 12 mm and is formed along the outer diameter surface of the tube 2. The outer fin 10 has a wave shape in which the protrusions 11 and the settled portions 12 are alternately formed in the circumferential direction of the tube 2 in order to improve the heat transfer efficiency by increasing the heat transfer area and the nature of the fluid flow. Is fulfilling. Since the protrusions 11 and the settled portions 12 formed on the outer pin 10 are gently formed along the circumferential direction, the surface of the outer pin 10 forms a smooth streamline without sudden bending.

In addition, the protruding portion 11 and the settling portion 12 are formed over the entire surface of the outer fin 10 from the portion where the outer fin 10 is joined to the tube 2 to the end of the outer fin 10.

Figure 4 is a side view showing a first embodiment of a fin tube type heat exchanger according to the present invention. As shown in FIG. 4, the outer fin 10 is radially formed vertically from the outer diameter surface of the tube 2, and protrudes in the circumferential direction corresponding to the direction in which fluid flows around the tube 2. 11 and the settled portion 12 are formed alternately. The distance between adjacent outer pins 10 is about 2.54 mm.

The angle between the outer diameter surface of the tube 2 and the outer fin 10 is preferably 60 to 120 degrees, of which 90 degrees is most preferred. At an angle of 60 degrees or less and 120 degrees or more, the resistance of the fluid passing through the tube 2 becomes large, resulting in trembling and noise, and the pressure loss of the fluid becomes very large, causing unnecessary power consumption of the blower (not shown). In addition, as the angle between the outer diameter surface of the tube 2 and the outer fin 10 becomes smaller, the flow rate of the fluid passing through the tube 2 decreases, thereby lowering the cooling capacity.

Figure 3 is a side view showing a part of the inner fin of the first embodiment of the fin tube type heat exchanger according to the present invention. As shown in FIG. 3, the inner pin 5 formed inside the tube 2 travels along the center axis of the tube 2, and, like the teeth of the helical gear, has a constant rotation angle per traveling distance. It has a spiral shape. Accordingly, each subchannel formed by the plurality of inner fins 5 is also spirally formed along the center axis of the tube 2.

5 is a front view showing a second embodiment of the fin tube type heat exchanger according to the present invention. As shown in FIG. 5, the heat exchanger includes an inner tube 15 inserted therein and an outer tube 14 surrounding the outside of the inner tube 15.

The inner diameter surface of the inner tube 15 is formed along the central axis of the inner tube 15, the spiral inner pin 5 having a constant rotation angle per traveling distance, such as the teeth of the helical gear is formed is formed On both sides of the inner fin 5, hemispherical fine fins 7 having a radius of about 0.4 mm are formed over the entire surface to increase the heat transfer area.

The inner tube 15 is embedded in the outer tube 14, and the outer diameter surface of the outer tube 14 and the outer diameter surface of the inner tube 15 are press-fitted. On the outer diameter surface of the outer tube 14, an outer fin 10, which is an annular thin plate having a height of about 12 mm, is formed. The outer fin 10 is settled with the protrusion 11 along the circumferential direction of the tube 2. The portions 12 are alternately formed to form a wave shape.

The tube 2, the outer fin 10, the inner fin 5 and the like are preferably a metal material, and copper is used in the present invention.

6 is a perspective view showing a condenser of an air conditioner according to the present invention, and FIG. 6A is an enlarged view of a portion A of FIG. 6. As illustrated in FIGS. 6 and 6A, annular U-shaped tube guides 33 are positioned at upper and lower portions of the condenser 30, respectively, and a plurality of first U-shaped tube guide holes formed in the U-shaped tube guides 33. Each of the tubes 34 is inserted with a plurality of inner pins 5 on the inner diameter surface and a plurality of outer pins 10 on the outer diameter surface. The plurality of tubes 2 are installed vertically along the first U-tube guide hole 34 formed in the U-tube guide part 33 constituting the upper and lower portions of the condenser 30 to form a circular fence shape. The condenser 30 is configured.

Of the plurality of first U-tube guide holes 34 formed in the U-tube guide part 33, the two tubes 2 exposed through the two first U-tube guide holes 34 are compressors (not shown). It is connected to the inlet portion 35 of the tube (2) form the two perpendicularly bent so that the refrigerant 25 passing through.

The ends of the two tubes 2, which are located in the condenser 30 opposite the tubes 2 connected to the inlet 35, have an upper portion for discharging the refrigerant 25 from the condenser 30 to the evaporator. It passes through two first U-tube guide holes 34 located at and connected to two tubular outlet portions 37 that are bent at right angles.

The end of the tube 2 protruding through the first U-tube guide hole 34 is the end of the tube 2 protruding through the first U-tube guide hole 34 located next and the U-tube 36. Are connected by two U-tubes 36 at the bottom of the condenser 30 and two tubes 2 adjacent to each other.

That is, when the tubes 2 constituting the condenser 30 are connected to the adjacent tube 2 at the top of the condenser 30, the connected tube 2 is connected to the next adjacent tube 2 at the bottom of the condenser 30. Through the format, the plurality of tubes 2 are alternately connected from the inlet part 35 to the outlet part 37 by repeating the connection at the upper and lower parts. In the condenser 30, the inlet part 35 and the outlet part 37 are installed two by one, so that half of the entire tube 2 is clocked by the U-shaped tube guide part 33 from one of the two inlet parts 35. It is connected to the discharge part 37 along the direction path, and the other half tube 2 is connected to the discharge part 37 along the counterclockwise path from the other one inlet part 35.

7 is a perspective view showing an evaporator of the air conditioner according to the present invention, FIG. 7A is an enlarged view of a portion B of FIG. 7, and FIG. 8 is a left side view showing the evaporator of the air conditioner according to the present invention. As shown in Figs. 7 and 7A, a U-tube guide plate 43 is formed at the top and bottom, and each of the U-tube guide plate 43 has a second U-tube guide hole 44 for guiding the arrangement of the tube 2; ) Is formed in three rows.

In each of the second U-tube guide holes 44, a tube 2 constituting the fin tube type heat exchanger according to the first embodiment of the present invention is inserted. The tubes 2 installed in the first row from the front of the evaporator 40 are passages through which the refrigerant flows from the condenser to the evaporator and are connected to an inlet manifold 42 installed below the evaporator 40. The inlet manifold 42 is formed with one inlet manifold inlet 45 through which the refrigerant flows from the condenser and a plurality of inlet manifold outlets 46 which send the refrigerant to the evaporator 40.

As shown in FIG. 8, the plurality of tubes 2 installed in three rows are connected to each other via a U-shaped tube 36. The tubes 2 installed in the third row are connected to the discharge manifold 41 located above the evaporator 40. Each tube 2 installed in the third row is connected to a plurality of discharge manifold inlets 48 formed in the discharge manifold 41, and the discharge manifold 41 has one discharge manifold outlet ( 49) are formed.

Hereinafter, the operation of the fin tube type heat exchanger according to the present invention will be described.

The inner fins 5 of the fin tube type heat exchanger are helical with respect to the center axis of the tube 2, and as a result, the subchannels 4 are helically formed, so that the direction of the fluid passing through the heat exchanger is constant. Therefore, the fluid flowing through the subchannel 4 at any particular position according to the circumferential angle of the tube 2 is more or less heat exchanged than the fluid flowing through the other channel, so that this is to prevent and equalize the heat exchange amount. . In addition, the internal fins 5 have a merit that the heat transfer area is larger than that of the straight line to form a spiral.

The fine fins 7 are formed on both sides of the inner fins 5 in order to increase the heat transfer coefficient of the heat exchanger. The heat transfer area of the fin tube type heat exchanger is increased by about 300% compared to the general tube 100 by the spiral inner fin 5, and the heat transfer coefficient when evaporating or condensing by the micro fins 7 formed on the inner fin 5 Increases by about 70%.

In order to improve the heat transfer effect inside the tube 2, an external fin 10 is installed to increase the heat transfer area of the outer diameter surface of the tube 2 and at the same time, a method of hydrodynamically increasing the heat transfer coefficient is used. By making the shape of the outer pin 10 into a wave shape having the protrusions 11 and the settling portion 12, when the fluid strikes the protrusions 11, the flow rate of contacting the protrusions 11 is increased, and in the settling portion 12, Vortex occurs to increase the flow rate in contact with the settling portion 12. As a result, the heat transfer efficiency of the fin tube type heat exchanger is greatly improved.

Hereinafter will be described the operation of the air conditioner including a fin tube type heat exchanger according to the present invention.

First, the condenser 30 and the evaporator 40 will be described. As shown in FIG. 6, the condenser 30 is driven by a blower (not shown) installed at the upper portion of the air 20 to condenser 30. Heat exchange through the fin tube type heat exchanger from all sides of the) and is discharged to the upper portion of the condenser (30).

As shown in FIG. 8, the evaporator 40 has three rows of tubes 2 arranged therein, and the refrigerant introduced through the inflow manifold 42 by the blower (not shown) installed at the rear and the surrounding air ( 21 passes through the tube 2 three times to exchange heat, and the refrigerant is discharged back to the compressor (not shown) via the discharge manifold 41.

The resources of the condenser 30 and the evaporator 40 used in the air conditioner are shown in the following Table 1 condenser resource table and Table 2 evaporator resource table.

Specification Existing Cycle Cycle of the Invention Tube diameter (mm) 15.88 15.88 Pipe thickness (mm) One One Pin height (mm) 12 12 Pin thickness (mm) 0.45 0.45 Tube length (mm) 800 850 Number of tubes (2) 26 56 Distance between fluid flow and vertical tube (2) (mm) 43 43 Number of pins in the tube 5 5 Pin thickness in pipe (mm) 2 2 Fine pin height (mm) 0.4 0.4 Air flow rate (kg / s) 3 5.4 Air pressure loss (mmH ₂ O) 4.9 3.6 Pressure loss in the pipe (mmH ₂ O) 40.8 91.7 Air inlet temperature (℃) 35 35 Required Blowing Power (W) 121 169

Specification Existing Cycle Cycle of the Invention Tube diameter (mm) 15.88 15.88 Pipe thickness (mm) One One Pin height (mm) 12 12 Pin thickness (mm) 0.45 0.45 Tube length (mm) 750 800 Number of tubes (2) 33 42 Distance between fluid flow and vertical tube (2) (mm) 43 43 Distance between tubes (2) in the same direction as the fluid flow (mm) 40 40 Number of pins in the tube 5 5 Pin thickness in pipe (mm) 2 2 Fine pin height (mm) 0.4 0.4 Air flow rate (kg / s) One 1.2 Air pressure loss (mmH ₂ O) 8.9 9.3 Pressure loss in the pipe 1.65 0.78 Air inlet temperature (℃) 27 27 Air outlet temperature (℃) 13.7 16.3 Required Blowing Power (W) 74 94

The temperature of the air and the like set in the resources of the condenser and the evaporator is assumed in consideration of the temperate climate region of the Republic of Korea, the average temperature of the summer in 40 degrees or less.

Hereinafter, an operation cycle of the air conditioner using the condenser and the evaporator will be described.

In the case where R-22 is used as the refrigerant, when the refrigerant passes through the compressor, the condenser and the evaporator, the compressor (not shown) adiabaticly compresses the gas refrigerant of 645kpa to 1612kpa, where the refrigerant becomes an overheated steam of 81 degrees. The superheated steam is sent to the condenser, cooled to 42.5 ° C and then condensed completely and sent to the expansion valve supercooled by 2 ° C, and adiabatic expansion at the expansion valve results in pressure of 654.9kpa. During this adiabatic expansion, the refrigerant evaporates 19.6% and the remaining 80.4% evaporates in the evaporator. At this time, the saturation temperature is 10 degrees higher than the saturation temperature of the evaporator of the air conditioner using a conventional tube heat exchanger. The gas refrigerant evaporated in the evaporator is sent to the compressor, which completes the cycle.

Compared with the conventional tube, the condenser is operated at a condenser temperature of about 8 degrees lower, and the evaporator is operated at a temperature of about 3 degrees higher. As high as the result was brought.

Such a high efficiency operation cycle is possible because the tube 2 used in the condenser and the evaporator has a high heat transfer capacity, and thus the condenser temperature of the condenser can be 42.5 degrees.

In the preferred embodiment of the present invention, the outer fin 10 of the tube 2 has a wave shape having a protrusion and a settled portion, but the present invention is not limited to this, it is also possible to use a flat outer fin 10.

In addition, in the preferred embodiment of the present invention, the condenser has a cylindrical shape, but the present invention is not limited thereto, and the present invention may be triangular, square, pentagonal, hexagonal, or octagonal.

In addition, the refrigerator according to the present invention can be widely applied to a device having a refrigeration function, such as a refrigerator, a freezer.

In addition, in the preferred embodiment of the present invention, the fin tube type heat exchanger is used as an air conditioner and a refrigerator, but the present invention is not limited thereto.

In addition, in the preferred embodiment of the present invention, the material of the tube 2, the outer fin 10 and the inner fin 5 is made of copper, but the present invention is not limited thereto, and various metal materials such as stainless steel and brass are used. It is possible.

As described in detail above, the fin tube type heat exchanger according to the present invention can be applied to domestic and industrial air conditioners, refrigerators, refrigerator cars, air conditioners, and the like, and can save energy and protect the environment because it can achieve the same cooling effect while consuming less power. Will bring the effect of.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. Accordingly, the appended claims will cover such modifications and variations as fall within the spirit of the invention.

Claims (14)

In the heat exchanger, Fin tube type heat exchanger, characterized in that it comprises a tube (2) having a plurality of inner fins (5) on the inner diameter surface and a plurality of outer fins (10) on the outer diameter surface. The fin tube type heat exchanger according to claim 1, wherein the inner fin (5) extends radially from a central axis of the tube (2) to an inner diameter surface of the tube (2). 3. Finned tube heat exchanger according to claim 2, characterized in that the inner fins (5) are formed helically along the central axis of the tube (2). The fin tube type heat exchanger according to any one of claims 1 to 3, wherein each of the inner fins (5) is provided with a plurality of fine fins (7) protruding in a hemispherical shape on the surface. The fin tube type heat exchanger according to claim 1, wherein the outer fin (10) is formed of an annular thin plate having a predetermined height along the outer diameter surface of the tube (2). According to claim 1 or 5, wherein the outer fin 10 is characterized in that the protrusions 11 and the settled portion 12 are alternately formed in the circumferential direction of the tube (2) to form a wave shape. Tubular Heat Exchanger. 7. The fin tube type heat exchanger according to claim 6, wherein the outer fin (10) increases as the distance between each adjacent protrusion (11) and the settling portion (12) increases in the radial direction. 7. The fin tube type heat exchanger according to claim 6, wherein the outer fin (10) is formed at an angle between 60 and 120 degrees with an outer diameter surface of the tube (2). An inner tube 15 having a plurality of inner pins 5 on the inner diameter surface; And Fin tube type heat exchanger, characterized in that it comprises a plurality of outer fins 10 is formed on the outer diameter surface and the outer tube 14 is pressed into the inner tube 15 on the inner diameter surface. In the air conditioner, A condenser 30 comprising a heat exchanger comprising a plurality of inner fins 5 on the inner diameter surface and a tube 2 having a plurality of outer fins 10 formed on the outer diameter surface; And An air conditioner comprising an evaporator (40) comprising a heat exchanger comprising a plurality of inner fins (5) on the inner diameter surface and a tube (2) having a plurality of outer fins (10) formed on the outer diameter surface. 13. The air conditioner according to claim 12, wherein the condenser (30) is characterized in that a plurality of the tubes (2) are arranged in a square or a cylindrical shape. The method of claim 13, wherein the evaporator 40, An inlet manifold (42) connected to each of the plurality of tubes (2) arranged at one side of the evaporator (40); A discharge manifold (41) connected to each of the plurality of tubes (2) arranged on the other side of the evaporator (40); And An air conditioner characterized by having a U-shaped tube 36 coupled to an end of each of the tubes 2 to interconnect each of the plurality of tubes 2 arranged in one row with the tubes 2 in adjacent rows. . 13. The air conditioner according to claim 12, wherein the condenser (30) or the evaporator (40) is formed by standing the tube (2) vertically. In the freezer, And a heat exchanger comprising a plurality of inner fins 5 on the inner diameter surface and a tube 2 having a plurality of outer fins 10 formed on the outer diameter surface.