CN201945095U - Dry evaporator with double face reinforced tube bundle supported by helical baffle plate - Google Patents

Abstract

The utility model discloses a double-sided reinforced tube bundle dry-type evaporator supported by a spiral baffle, which comprises a head, a shell, a spiral baffle, a heat transfer tube, a fixed-distance tube, and a tube plate. There are spiral baffles, heat transfer tubes and spacer tubes, and the spiral baffles are fixed by spacer tubes; the heat transfer tubes are double-sided reinforced tubes, with two-dimensional or three-dimensional fins on the outer surface of the tube wall, and the tube wall There are grooves on the inner surface; the distance tube and the heat transfer tube pass through the spiral baffle, and are supported by the spiral baffle, and the two ends are respectively connected with the tube plate; there is a refrigerant outlet on the head And the inlet, the inlet and outlet of the brine are provided on the shell. The dry evaporator of the utility model has the advantages of uniform fluid flow, low pressure drop, no dead zone, no scaling, high heat transfer coefficient, low flow resistance, etc., and can be widely used in large and medium-sized air conditioner chillers.

Description

A double-sided reinforced tube bundle dry evaporator supported by spiral baffles

technical field

The utility model patent relates to the technical field of heat transfer equipment, in particular to a double-sided reinforced tube bundle dry evaporator supported by a spiral baffle.

Background technique

Dry evaporators are widely used in large and medium-sized air-conditioning chillers. In the dry evaporator, refrigerants such as freon and ammonia flow in the heat transfer tube, and refrigerants such as calcium chloride or ethylene glycol aqueous solution flow in the outer shell of the heat transfer tube; the refrigerant in the tube exchanges with the refrigerant outside the tube. After heating, the temperature rises and evaporates from the liquid phase to the gas phase. After heat exchange between the refrigerant outside the tube and the refrigerant inside the tube, the temperature decreases; at the same time, a baffle is arranged on the shell side to support the heat transfer tube and guide the refrigerant flow in a specific channel. At present, the smooth tube-bundle dry evaporator supported by bow-shaped baffles is the most commonly used form of dry evaporators. This type of dry evaporator has the following disadvantages:

1. The brine is baffled back and forth between the baffles to scour the heat transfer tube bundles. During this process, the baffles will cause large fluid resistance and high pressure drop, which will easily cause the vibration damage of the tube bundles;

2. There is a flow dead zone in the bow-shaped partition, and the medium is easy to scale, which affects the performance and service life of the heat exchanger;

3. Smooth tubes are used for heat exchange, and the heat transfer efficiency is low, which will increase the volume and cost of the dry evaporator.

The dry evaporator using spiral baffles as the support structure between the tubes can overcome the inherent shortcomings of the bow-shaped baffles supporting the dry evaporator. The brine flows in the shell side, with uniform flow, no dead zone, and low pressure drop. And it is not easy to cause the vibration of the tube bundle; the combination of the spiral baffle and the double-sided strengthening tube can further improve the heat transfer performance of the dry evaporator, thereby reducing the volume and cost of the dry evaporator.

There are existing Chinese patents related to technical improvements of dry evaporators and intensified tubes. Chinese utility model patent CN2783247Y discloses that spiral baffles are applied to dry evaporators and condensers to improve the performance of evaporators and condensers, but this patent does not involve the application of enhanced heat transfer tubes. Chinese utility model patent CN201191106Y also discloses the application of spiral baffles in dry evaporators. The heat transfer tubes involved in this patent are smooth tubes and internally threaded tubes, which are not heat transfer tubes with double-sided enhanced heat transfer performance. Chinese utility model patent CN2809564Y discloses a double-sided reinforced tube for dry evaporators. The outer surface of the reinforced tube is circumferentially arranged fins, and the inner surface of the tube has rifling internal threads and circumferentially arranged fixing fins. Interval grooves, the grooves separate the internal threads into discontinuous forms, and the grooves correspond to the positions of the fins on the outer wall of the tube. This patent only relates to a kind of enhanced heat transfer tube, and does not relate to the spiral baffle dry type evaporator.

Utility model content

The purpose of the utility model is to overcome the shortcomings of the existing baffle dry-type evaporator, and provide a spiral baffle-supported double-sided reinforced tube bundle dry-type evaporator. The dry-type evaporator has uniform fluid flow, low pressure drop, It has the advantages of no dead zone, not easy to scale, high heat transfer coefficient, low flow resistance, and strong resistance to medium corrosion.

The purpose of this utility model is achieved through the following technical solutions:

A spiral baffle supported double-sided reinforced tube bundle dry evaporator, including a head 1, a shell 3, a spiral baffle 4, a heat transfer tube 5, a distance tube 6 and a tube sheet 8, and the tube sheet 8 There are spiral baffles 4, heat transfer tubes 5 and distance tubes 6, and the spiral baffles 4 are fixed by the distance tubes 6; the heat transfer tubes 5 are double-sided reinforced tubes; the distance tubes 6 and the distance tubes The heat pipe 5 passes through the spiral baffle 4, is supported by the spiral baffle 4, and the two ends are respectively connected with the tube sheet 8; the outlet 9 of the refrigerant and the inlet 10 of the refrigerant are arranged on the head 1, and the The shell 3 is provided with an inlet 2 for brine and an outlet 7 for the brine after heat exchange.

The double-sided reinforced tube of the utility model is a heat transfer tube with two-dimensional or three-dimensional fins on the outer surface of the tube wall and grooves on the inner surface of the tube wall.

The structural parameters of the groove described in the utility model are: the groove depth is 0.3-0.6 mm, and the groove width is 0.4-1.0 mm.

The material of the heat transfer tube 5 in the present invention is carbon steel, titanium, red copper or copper alloy.

The heat transfer tubes 5 described in the utility model form tube bundles according to triangular tube layout, corner triangle tube layout, square tube layout, corner square tube layout or concentric circle tube layout.

The spiral baffle in the utility model is a quarter elliptical plate inclined to the central axis of the heat exchanger, and four elliptical baffles are cross-arranged and spliced into a helical shape along each circumference of the radial direction of the tube bundle. The periphery of the adjacent baffles is a continuous helical line; or it is an overall continuous helical structure, and the center of the tube bundle is provided with a central tube.

The material of the spiral baffle in the utility model is carbon steel, stainless steel or engineering plastics.

The dry evaporator described in the utility model is one of fixed tube plate type, floating head type or U-shaped tube type.

Compared with the prior art, the utility model has the following beneficial effects:

1. The spiral baffle makes the fluid flow evenly in the shell side, showing a continuous and stable spiral plug-like flow. The flow of the fluid is less mixed, and there is no flow dead zone, so the brine is not easy to scale on the shell side.

2. The influence of the bypass flow and leakage flow of the fluid is small, and the pressure is low, so the vibration damage to the tube bundle caused by the refrigerant during the flow process is small.

3. The double-sided enhanced tube is used as the heat transfer tube type. The two-dimensional or three-dimensional fins on the outer surface can increase the heat exchange area, and promote the strong turbulence of the brine during the flow outside the tube, and promote the boundary layer. Disturbance and separation, so as to improve the convective heat transfer coefficient outside the tube; the grooves between the two-dimensional fins on the inner surface can also increase the heat exchange area in the tube, and provide the vaporization core when the refrigerant evaporates in the tube and promote flow The process produces strong turbulence, thereby increasing the evaporation heat transfer coefficient in the tube; because the heat transfer coefficient inside and outside the tube is improved, the dry evaporator has a high heat transfer coefficient.

4. Combining the advantages of spiral baffles and double-sided reinforced tubes, the dry evaporator has high heat transfer coefficient, stable performance, low pressure drop, and is not easy to scale. It is especially suitable for application in large and medium-sized air-conditioning chillers.

Description of drawings

Fig. 1 is a structural schematic diagram of a double-sided reinforced tube-bundle dry evaporator supported by spiral baffles of the present invention.

Fig. 2 is a structural schematic diagram of splicing quarter elliptical plates into a tube bundle of spiral baffles.

Fig. 3 is a structural schematic diagram of an integral spiral baffle tube bundle provided with a central tube.

Fig. 4 is a schematic structural diagram of a double-sided reinforced tube. Two-dimensional fins or three-dimensional fins are provided on the outer surface of the tube wall, and grooves are provided on the inner surface of the tube wall.

Fig. 5 is a structural schematic diagram of a two-dimensional fin, and the structural parameters are fin height h and fin pitch p.

FIG. 6 is a schematic diagram of the structure of the trench, and the structural parameters are the trench depth h and the trench width p.

Fig. 7 is a structural schematic diagram of a three-dimensional fin, and the structural parameters are fin height h, fin pitch P1 and fin gap P2.

8 is a cross-sectional view of a double-sided reinforced tube provided with three-dimensional fins on the outer surface of the tube wall.

Fig. 9 is an equilateral triangle layout diagram of heat transfer tubes.

Detailed ways

The utility model will be described in detail below in conjunction with the accompanying drawings, but the embodiments of the utility model are not limited thereto.

As shown in Figure 1, the spiral baffle supports the double-sided reinforced tube bundle dry evaporator of the present invention, including a head 1, a shell 3, a spiral baffle 4, a heat transfer tube 5, a distance tube 6 and The tube sheet 8 is provided with a spiral baffle 4, a heat transfer tube 5 and a distance tube 6 between the tube sheets 8, and the spiral baffle 4 is fixed by the distance tube 6; the heat transfer tube 5 is a double-sided reinforced tube; The distance tube 6 and the heat transfer tube 5 pass through the spiral baffle 4, and are supported by the spiral baffle 4, and the two ends are respectively connected with the tube sheet 8; The inlet 10 of the agent, the inlet 2 of the brine and the outlet 7 of the low-temperature brine after heat exchange are provided on the shell 3 . Figure 1 shows a fixed tube-sheet heat exchanger.

As shown in Figures 2 and 3, the spiral baffle 4 is a quarter elliptical plate 32 inclined to the central axis of the heat exchanger. Helical shape, the periphery of each adjacent baffle is a continuous helical line; or an overall continuous helical structure, and the center of the tube bundle is provided with a central tube 22 .

As shown in Figure 4, the heat transfer tube 5 is a double-sided reinforced tube, two-dimensional or three-dimensional fins are arranged on the outer surface of the tube wall of the double-sided reinforced tube, and grooves are arranged on the inner surface of the tube wall; The material is carbon steel, titanium, copper or copper alloy.

As shown in Figure 5, the structural parameters of the two-dimensional fins on the outer surface of the tube wall of the double-sided reinforced tube are: the fin height h is 0.8-2.0 mm, and the fin pitch p is 1.0-1.5 mm.

As shown in Figure 6, grooves are provided on the inner surface of the pipe wall of the double-sided reinforced pipe, and the structural parameters are: the groove depth h is 0.3-0.6mm, and the groove width p is 0.4-1.0mm.

As shown in Fig. 7, it is a structural schematic diagram of a three-dimensional fin, and the structural parameters are: the fin height h is 0.8-2.0mm, the fin distance P1 is 1.0-1.5mm, and the fin gap P2 is 1.2-1.5mm.

Figure 8 is a cross-sectional view of a double-sided reinforced tube with three-dimensional fins on the outer surface of the tube wall.

As shown in FIG. 9 , the heat transfer tubes 5 can be arranged in an equilateral triangle.

Claims (7)

1. a helical baffles supports two-sided strengthened pipe tube bank dry evaporator, comprise end socket (1), housing (3), helical baffles (4), heat-transfer pipe (5), distance sink tube (6) and tube sheet (8), it is characterized in that, be provided with helical baffles (4), heat-transfer pipe (5) and distance sink tube (6) between tube sheet (8), helical baffles (4) is fixing by distance sink tube (6); Described heat-transfer pipe (5) is two-sided strengthened pipe; Distance sink tube (6) and heat-transfer pipe (5) pass helical baffles (4), adopt helical baffles (4) to support, and two ends are connected with tube sheet (8) respectively; On end socket (1), be provided with the outlet (9) of cold-producing medium and the import (10) of cold-producing medium, the outlet (7) of refrigerating medium after import (2) that is provided with refrigerating medium on the housing (3) and heat exchange.

2. helical baffles according to claim 1 supports two-sided strengthened pipe tube bank dry evaporator, it is characterized in that described two-sided strengthened pipe is that outer surface of tube wall is provided with two dimension or three-dimension fin, and inner surface of tube wall is provided with the heat-transfer pipe of groove.

3. helical baffles according to claim 2 supports two-sided strengthened pipe tube bank dry evaporator, and it is characterized in that the structural parameters of described groove are: groove depth is 0.3～0.6mm, and groove width is 0.4～1.0mm.

4. helical baffles according to claim 1 supports two-sided strengthened pipe tube bank dry evaporator, it is characterized in that the material of described heat-transfer pipe (5) is carbon steel, titanium, red copper or copper alloy.

5. helical baffles according to claim 1 supports two-sided strengthened pipe tube bank dry evaporator, it is characterized in that described heat-transfer pipe (5) is pressed triangle stringing, corner triangle stringing, square stringing, corner square stringing or concentric circles stringing and formed tube bank.

6. helical baffles according to claim 5 supports two-sided strengthened pipe tube bank dry evaporator, it is characterized in that, described helical baffles is by 1/4th ellipses that tilt with the heat exchanger central axis, radially each circumference is with four oval deflection plate cross arrangements and be spliced into helical form along tube bank, and each adjacent baffle periphery is the continuous helical line; Or be whole continuous helical structure, and the center of tube bank is provided with central tube.

7. support two-sided strengthened pipe tube bank dry evaporator according to claim 1 or 6 described helical baffles, it is characterized in that the material of described helical baffles is carbon steel, stainless steel or engineering plastics.

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