WO2016119366A1

WO2016119366A1 - Closed cooling tower having tubesheet combined heat exchange piece

Info

Publication number: WO2016119366A1
Application number: PCT/CN2015/081394
Authority: WO
Inventors: 李志明; 谭栋; 张勇
Original assignee: 广州市华德工业有限公司
Priority date: 2015-01-28
Filing date: 2015-06-12
Publication date: 2016-08-04
Also published as: CN105987619A; CN105987619B

Abstract

A closed cooling tower having a tubesheet combined heat exchange piece, comprising a tubesheet combined heat exchanger (8), a blower(4), a solution pump (5), a spray shower (6), a solution reservoir (7) and a frame (9); the combined heat exchanger of tube sheet (8) is formed by connecting a plurality of tubesheet combined heat exchange pieces with an inlet header and an outlet header; the tubesheet combined heat exchange piece comprises a heat transfer plate (2) and a coil pipe (1) formed by processing a heat exchange pipe; the heat transfer plate (2) is provided with a mounting groove (21), and the shape of the mounting groove (21) matches the shape of the coil pipe (1); the coil pipe (1) is mounted inside the mounting groove (21), and the gap between the coil pipe (1) and the mounting groove (21) is filled with a heat conductive bonding layer (3), the heat conductive bonding layer (3) enabling full contact between the heat transfer plate (2) and the coil pipe (1), so as to increase an effective heat exchange area of the coil pipe (1); the heat transfer plate (2) can guide a solution to form a continuous flow surface face and increase a solution heat exchange surface area, improving the heat exchange efficiency as well as reducing the cooling tower volume.

Description

Closed cooling tower with plate tube composite heat exchange sheet

Technical field

The invention relates to the field of heat exchange equipment, in particular to a plate type and coil type composite heat exchange type closed cooling tower.

Background technique

At present, the closed cooling towers in the market are equipped with heat exchangers, fans and sprinklers. The coils used are transverse coils. The outer surface of the heat exchanger tubes of the coils is generally smooth and has low heat exchange efficiency. The evaporation heat transfer area of the solution is small, and the spacing of the coils needs to be enlarged to increase the heat exchange time between the cooling solution and the air, so that the entire coil is bulky. On the other hand, since there is no medium to guide the solution (cooling water or antifreeze) flowing between the upper and lower tubes of the coil, when the solution outside the tube drops from the top, the solution outside the tube is disordered under the traction of the vertical wind direction. Fluttering is easy to produce drift, the solution film outside the coil is not uniform, easy to store dry spots, reduce heat exchange capacity and there is a risk of scaling. The circulating wind direction is perpendicular to the coil (that is, the circulating wind passes through the plane space formed by each heat exchange tube and is perpendicular to the straight pipe section of the heat exchange tube), and the coil has a windward side and a leeward side, and is lacking in the leeward side. Air convection heat transfer reduces coil heat transfer efficiency. In order to ensure the amount of heat exchange, the length of the coil to be used needs to be increased, and the cost is greatly increased due to the increased use of the metal material.

Summary of the invention

In view of the above-mentioned deficiencies of the prior art, the technical problem to be solved by the present invention is to change the disk. The heat exchange structure of the tube increases the heat exchange efficiency to a greater extent.

In order to solve the above technical problem, the technical solution adopted by the present invention is a closed cooling tower with a plate tube composite heat exchange sheet, which comprises a plate and tube composite heat exchanger, a fan, a solution pump, and a shower. a solution tank and a frame; the plate-tube composite heat exchanger is composed of a plurality of plate-tube composite heat exchange sheets connected through an inlet header and an outlet header; the plate-tube composite heat exchange sheet includes a heat transfer plate and a coil processed by the heat exchange tube; the heat transfer plate is provided with a seating groove, the shape of the receiving groove is matched with the shape of the coil; the coil is placed in the mounting groove, and the gap between the coil and the mounting groove Filled with a thermally conductive adhesive layer. The heat transfer plate can guide the spray cooling water from the upper heat exchange tube to the lower heat exchange tube to improve the utilization of the cooling water; and at the same time, the heat conductive adhesive layer fills the gap between the full coil and the heat transfer plate to make the disk The tube is in full contact with the heat transfer plate, and the heat transfer plate becomes a rib of the coil, increasing the effective heat exchange area of the coil.

Preferably, the thermally conductive adhesive layer is a metal filler. Such a structure can be realized by soaking liquid metal and then cooling, so that the heat conductive adhesive layer can be sufficiently filled into the gap, and the heat conductivity of the metal is good, thereby further improving the rib formation of the heat transfer sheet.

More preferably, the gap between the coil and the seating groove is less than 10 mm. Such a structure has a small gap. When liquid metal immersion is performed, due to the viscosity of the liquid metal, the liquid metal may cause capillary action, and after penetrating into the inner surface of the heat transfer plate and the coil contact surface, a contact surface can be formed in the contact surface. The uniform thin packing not only completely fuses the heat transfer sheet and the coil into a whole, but also the filling layer is thin, thereby reducing the contact thermal resistance between the heat transfer sheet and the coil.

More preferably, the heat transfer sheet is also stamped with a plurality of limiting slots and/or positioning pads. Such a structure can ensure that the gap between the coil and the heat transfer plate can be immersed in the liquid metal The guarantee is small enough.

Preferably, the metal filler is one or more of zinc, tin, aluminum, and copper. These metals have low melting point and low price, and are used for liquid metal immersion, which is extremely cost-effective.

In a preferred embodiment, the thermally conductive adhesive layer is a thermally conductive adhesive. Direct use of thermal adhesives makes processing easier.

Preferably, the plate-tube composite heat exchange fin is disposed longitudinally, that is, the cooling wind blown by the fan flows along a substantially length direction of the coil. The cooling wind direction is consistent with the length of the coil, and there is no leeward surface, which reduces the dry point of the heat exchange coil surface and reduces the risk of scaling of the heat exchange coil.

Compared with the prior art, the closed cooling tower with the plate tube composite heat exchange sheet of the invention has the following beneficial effects:

1) The thermal conductive adhesive layer makes the heat transfer plate and the coil fully contact, so that the coil can generate a ribbing effect through the heat exchange plate and increase the effective heat exchange area;

2) The heat exchange plate can simultaneously drain the solution to form a continuous solution flow surface, and increase the heat exchange surface area of the solution;

It not only improves the heat exchange efficiency, but also helps to reduce the cooling tower volume.

The above description is only an overview of the technical solutions of the present invention, and the above-described and other objects, features and advantages of the present invention can be more clearly understood. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments will be described in detail with reference to the accompanying drawings.

DRAWINGS

1 is a schematic view showing the structure of a closed cooling tower with a plate-tube composite heat exchange sheet according to the present invention; Figure.

2 is a structural schematic view of a plate-tube composite heat exchange sheet of a closed cooling tower with a plate-tube composite heat exchange sheet according to the present invention.

3 is a schematic view showing the structure of a heat transfer plate of a plate-tube composite heat exchange sheet of a closed cooling tower with a plate-tube composite heat exchange sheet according to the present invention.

Figure 4 is a cross-sectional view taken along line A-A of Figure 2;

Fig. 5 is a structural schematic view showing an air conditioning system of a closed cooling tower with a plate-tube composite heat exchange sheet according to the present invention.

detailed description

The specific embodiments, structures, features and functions of the present invention are described in detail below with reference to the accompanying drawings and preferred embodiments, in which:

As shown in FIG. 1 , a closed cooling tower with a plate and tube composite heat exchange sheet of the present invention provides cooling water for a condenser of an air conditioning system during cooling in summer, and extracts air with water or antifreeze when heating in winter. The heat source in the middle. The closed cooling tower comprises a plate and tube composite heat exchanger 8, a fan 4, a solution pump 5, a shower 6, a solution tank 7 and a frame 9; the plate tube composite heat exchanger 8 is located in the shower 6 and the solution tank 7 The sprinkler 6 is in communication with the solution tank 7 through a solution pump 5 which is mounted to the frame 9 and is located at one end of the plate tube composite heat exchanger 8. The plate tube composite heat exchanger 8 is composed of a plurality of plate tube composite heat exchange sheets connected through an inlet header and an outlet header; the plate tube composite heat exchange sheet includes a heat transfer sheet 2 and is processed by a heat exchange tube The coil 1 is formed (the processing may be to bend the long heat exchange tube into a coil, or to bend the section The heat exchange tube and the straight heat exchange tube are welded together to form a coil); the heat transfer sheet 2 is provided with a seating groove 21, the shape of the seating groove 21 is matched with the shape of the coil 1; the coil 1 is placed on the In the mounting groove 21, the gap between the coil 1 and the seating groove 21 is filled with a thermally conductive adhesive layer 3; the heat exchange medium inside and outside the coil 1 constitutes a closed cycle, and heat transfer between the two does not transfer mass.

In this embodiment, the coil 1 is formed by continuous S-shaped bending of the heat exchange tubes, wherein the straight sections of the heat exchange tubes are substantially parallel or non-parallel, and the coil 1 can also adopt other suitable for use in the evaporation condenser. shape. The heat exchange tube of the coil 1 may be a copper tube, a stainless steel tube or a galvanized steel tube, etc., and the cross-sectional shape of the internal flow passage may be a circular shape, an elliptical shape, a spiral shape, a corrugated shape or an olive shape. As can be understood by those skilled in the art, the inner and outer surfaces of the coil 1 can adopt a smooth surface, preferably an enhanced heat transfer surface provided with internal and external threads, and the outer surface of the coil 1 can also be provided with a hydrophilic or anti-corrosive coating. Floor. The coil 1 is provided with an inlet and an outlet of a flow passage for connection with an inlet header and an outlet header.

As shown in FIG. 3 and FIG. 4, the heat transfer plate 2 is provided with a receiving groove 21. In the embodiment, the receiving groove 21 is realized by punching the heat transfer plate 2, or may be produced. The heat transfer sheet 2 is directly formed; the shape of the seating groove 21 matches the shape of the coil 1. The coil 1 is placed in the seating groove 21, and a gap between the coil 1 and the seating groove 21 is filled with a thermally conductive adhesive layer 3. In this embodiment, the thermally conductive adhesive layer 3 is liquid zinc after cooling. The heat transfer plate 2 and the coil 1 are immersed in the high-temperature liquid zinc, so that the liquid zinc flows into the gap between the coil 1 and the seating groove 21, and the gap is filled, and the viscosity of the liquid metal makes the two adhere. When the liquid metal is cooled and solidified into a solid state, it becomes a thermally conductive adhesive layer 3, and is filled between the coil 1 and the seating groove 21, and the both are fixed. In addition to zinc, tin, aluminum, and Metals such as copper or metal combinations thereof have the characteristics of low melting point and low price, and are cost-effective.

Further, in this embodiment, the gap between the coil 1 and the seating groove 21 is less than 10 mm. When the liquid metal is immersed, due to the viscosity of the liquid metal, the liquid metal may undergo capillary action, infiltration and transmission. After the hot plate 2 and the inside of the contact surface of the coil 1, the thermally conductive adhesive layer 3 formed in the gap of the contact can be made uniform and thin, and the heat transfer sheet 2 and the coil 1 are completely fused together as a whole. Moreover, since the thickness of the thermally conductive adhesive layer 3 is thin, the contact thermal resistance between the heat transfer sheet 2 and the coil 1 is effectively reduced. The smaller the gap between the coil 1 and the seating groove 21, the more obvious the capillary action of the liquid metal permeation, the more uniform the thermal conductive adhesive layer 3 is formed, and the relative cost and processing difficulty are relatively large; the gap width of 10 mm is The cost is the best choice, and the gap width of 5 mm is the best cost-effective choice, and the optimal choice for uniformity within 3 mm. Furthermore, in order to ensure that the high temperature liquid metal is immersed, the distance between the coil 1 and the heat transfer plate 2 can be sufficiently small, and a plurality of limit grooves and/or positioning pads can be punched out on the heat transfer plate 2 (Fig. Not shown), before the immersion, the coil 1 is pre-fixed by the limit slot mounting or the positioning of the solder joint. It is also possible to pre-fix the two by means of a clamp, but the operation is complicated.

The heat of the coil 1 is conducted to the heat transfer sheet 2 through the thermally conductive adhesive layer 3, and the heat transfer sheet 2 becomes the rib of the coil 1, which greatly increases the heat exchange area and directly enhances the heat exchange effect of the coil 1; The hot plate 2 has the effect of guiding the cooling solution, so that the cooling solution forms a continuous water flow on the surface of the heat transfer plate 2, avoids the disordered flying water of the cooling solution, and improves the utilization rate of the cooling solution. In addition, since the heat transfer sheet 2 is integrated, the cooling solution at the coupling with the coil 1 can be prevented from flowing alternately, and the water distribution rate can be ensured.

On the other hand, the thermal conductive adhesive layer 3 can be replaced by a thermal conductive adhesive; the thermal conductive adhesive is evenly applied to the mounting groove 21 of the heat transfer plate 2, and the coil 1 is directly placed into the mounting groove 21. It can be bonded (for some thermal adhesives that need to be combined, it is also necessary to apply a matching thermal adhesive on the coil 1), which is easy to install and simple in process. However, the existing thermal conductive adhesives, such as silicone thermal conductive adhesives, epoxy resin AB adhesives, and polyurethane thermal conductive adhesives, are not as strong as zinc, aluminum, etc., and are prone to unevenness during the laminating process, resulting in unevenness. When the coil 1 is adhered to the seating groove 21, an air layer insulation phenomenon may occur, which affects heat exchange efficiency.

In addition, the heat transfer plate 2 can also be provided with openings, corrugations, bends, water guides, dovetail grooves, ribs and the like to achieve an effect of increasing the water distribution effect, preventing flying water, and enhancing the robustness. Further, a plurality of elongated holes, round holes or other shaped through holes (not shown) may be formed at the mounting groove 21, and when the coil 1 is placed in the seating groove 21, a part of the coil 1 may be exposed. Outside the tank 21, it can be directly contacted with the cooling solution. This method can increase the direct contact area between the coil and the cooling solution, and at the same time, the opening of the coil can disturb the heat transfer of the cooling solution due to the unevenness of the flow of the cooling solution, but The ribbing of the heat transfer sheets is weakened to some extent.

Working Process: As shown in FIG. 5, the closed cooling tower with the plate and tube composite heat exchange sheet of the present invention is applied to an air conditioning system (not limited to an air conditioning system), and further includes a compressor 11 and a water-cooled condenser 12 . The throttling device 13, the evaporator 14, and the circulation pump 15 form a refrigeration cycle system. The high-temperature fluid (refrigerant) is sent out from the outlet of the compressor 11, passes through the water-cooled condenser 12 in sequence, is cooled to become a low-temperature fluid, enters the throttling device 13 and the evaporator 14, and finally enters the compressor from the inlet of the compressor 11. Thereby forming a refrigeration cycle mode; At the same time, the plate-tube composite heat exchanger 8 and the water-cooled condenser 12 and the circulation pump 15 constitute a closed cooling water cycle, wherein the cooling water is heated and then enters the inlet 81 of the plate-tube composite heat exchanger when passing through the water-cooled condenser 12 The header is thereafter cooled and flows out of the outlet header 82.

The above embodiments are merely preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention belong to the present invention. The scope of the claim.

Claims

A closed cooling tower with a tube-tube composite heat exchange sheet, comprising: a tube-tube composite heat exchanger, a fan, a solution pump, a shower, a solution tank and a frame; The plurality of plate tube composite heat exchange sheets are composed of an inlet header and an outlet header; the plate tube composite heat exchange sheet comprises a heat transfer sheet and a coil tube processed by the heat exchange tube; the heat transfer plate The sheet is provided with a receiving groove, the shape of the receiving groove is matched with the shape of the coil; the coil is placed in the mounting groove, and the gap between the coil and the mounting groove is filled with a heat conductive adhesive layer.
The closed cooling tower with a composite tube heat exchanger sheet according to claim 1, wherein the heat conductive adhesive layer is a metal filler.
A closed cooling tower with a composite tube heat exchanger sheet according to claim 2, wherein the gap between the coil and the mounting groove is less than 10 mm.
The closed cooling tower with a composite tube heat exchanger sheet according to claim 3, wherein the heat transfer sheet is further stamped with a plurality of limiting slots and/or positioning pads.
The closed cooling tower with a tube-tube composite heat exchange sheet according to claim 2, wherein the metal filler is one or more of zinc, tin, aluminum and copper.
The closed cooling tower with a composite tube heat exchanger sheet according to claim 1, wherein the heat conductive adhesive layer is a heat conductive adhesive.
The closed cooling tower with a plate-tube composite heat exchange sheet according to claim 1, wherein the plate-tube composite heat exchange fin is longitudinally disposed, that is, the cooling wind blown by the fan is along the coil It flows in the approximate length direction.