KR200349474Y1 - Thermosiphon Heat Pipe Type Heat Exchanger - Google Patents

Abstract

The present invention relates to a heat pipe type shell tube heat exchanger in which a shell tube heat exchanger applies the operating principle of a thermosyphon heat pipe, and includes a shell (10) filled with a working fluid at a lower portion thereof, and various heat pipes are inserted therein. It is divided into upper and lower halves and consists of a lower heat pipe that forms a condensation part and a lower heat pipe that forms a condensation part by flowing a high temperature fluid. In addition, both sides of the shell is formed with a fixed tube plate and a removable bonnet bonnet is installed. In particular, the fixed tube plate and the bonnet have partition walls formed therein, and rubber packing is installed therebetween to completely separate the flow of hot and cold fluid to prevent mixing of the hot and cold fluid inside the bonnet. In order to operate a thermosyphon, the heat exchanger of the present invention must flow high temperature fluid toward the lower heat exchanger tube and low temperature fluid toward the upper heat exchanger tube.

Description

Thermosiphon Heat Pipe Type Heat Exchanger {Thermosiphon Heat Pipe Type Heat Exchanger}

The present invention relates to a thermosiphon heat pipe type heat exchanger in which a shell and tube heat exchanger is applied to a thermosiphon heat pipe.

Typical shell tube heat exchangers are widely used for industrial purposes.

For example, FIG. 1 exemplarily shows shell-side fluid flow of a conventional shell-and-tube heat exchanger as an arrow. As shown in FIG. 1, the shell-side fluid is designed to flow at right angles up and down by a baffle 1. It is increasing the heat transfer rate. These shell-and-tube heat exchangers are inexpensive, easy to maintain, can be manufactured in various sizes, and have good pressure resistance, making them widely used as industrial equipment for chemical plants and power generation facilities. The fields of application include the heaters and coolers (petroleum and gas refiners) of various process fluids, oil coolers for oil and hydraulic transformers, dryer heaters, wastewater recovery heat exchangers, etc., which make up about 60% of all industrial heat exchangers. It can be called a heat exchanger.

The heat transfer performance of the shell-and-tube type heat exchanger can be said to have a complexity that is greatly influenced by factors (parameters) such as the position and shape of the fluid inlet and outlet, the head type, and the shape and position of the barrier film 1. The heat transfer performance improvement method of the shell-and-tube type heat exchanger can be largely divided into a tube side and a shell side, and the tube side uses a highly efficient heat transfer tube, that is, a spiral tube, a corrugated tube, and an inner fin tube. On the shell side, various types of barrier films (eg, segmental baffles, disc donuts baffles, orifice baffles, etc.) are used in order to smoothly induce shell-side fluid flow. Segmental baffle is a general purpose baffle (blocking membrane) type that is easy and simple to manufacture heat exchanger. However, these baffles have a lot of dead space zones and a large pressure drop in the heat transfer area, and they tend to cause corrosion or pore due to fouling in the stagnant zones.

In order to solve this problem, there is a helix changer of ABB company, which induces the shell-side fluid flow spirally by processing the baffles installed on the shell side in three dimensions, and in Korea, a spiral heat exchanger (Wincool) of "Wincool" company. ) Has been developed and marketed, but ABB's products have difficulties in baffle processing and heat exchanger manufacturing process, the domestic "Wincool" 's product has the disadvantage of increasing the manufacturing cost and tube side heat transfer area.

Shell-and-tube heat exchangers are widely used as condensers in power plant plants. In the conventional condenser design, the most influential factor in the heat transfer efficiency of the condenser is the vacuum degree and the coolant inlet temperature in the condenser. Therefore, the optimum tube arrangement is required to maintain the degree of vacuum in the condenser and to facilitate the discharge of condensate. Therefore, the condenser size is excessively designed, and heat transfer tube vibration occurs due to the inflow of steam, resulting in fatal damage to the condenser. Existing multiplier designs are subject to many design constraints to improve heat transfer performance.

The present invention has been devised in view of the above, and has developed a thermosiphon heat pipe type heat exchanger capable of minimizing air-side heat transfer resistance and efficient heat transfer of steam, and the apparatus according to the present invention can be applied to a plurality of devices. Is of course

The heat exchanger according to the present invention firstly, the tube arrangement using the shell-side steam distribution and the tube arrangement for discharging condensate is not required, and secondly, there is no need for a sub cooling zone of the existing condenser, and third, stagnation of exhaust steam. There is no worry about, fourth, there is no vibration of the heat pipe due to the inlet steam, and fifth, it can solve the hunting problem to some extent.

1 is a flow diagram of the shell-side fluid flow of the shell and tube heat exchanger

Figure 2 is a view for explaining the principle of operation of the thermosiphon heat pipe to which the present invention is applied

3A is a front configuration diagram of a heat exchanger according to the present invention, and FIGS. 3B and 3C are views for explaining a side configuration of the bonnet and the fixed tube plate 40.

4A, 4B, and 4C correspond to other embodiments corresponding to FIGS. 3A, 3B, and 3C, respectively.

The main configuration of the present invention to solve the above problems, the shell 10 is filled with a working fluid in the lower, the lower heat pipe 88 is a high-temperature fluid flows inside, and the upper heat pipe is a low-temperature fluid flows therein And a bonnet 4 formed at the side of the shell 10 and having a high temperature inlet for inflow of high temperature fluid and a low temperature inlet for inlet of low temperature fluid, and a side of the shell 10. And a fixed tube plate 40 formed integrally with and coupled to the bonnet 4, and divided by the partition wall 44 between the bonnet 4 and the fixed tube plate 4. It is characterized in that the fluid is configured to be introduced so as not to be mixed with different temperatures, the bonnet (4) is formed in the cold import, outlet 39, 49 and the hot import, outlet (48, 38), and A partition wall 44 and a vertical wall 45 are formed between upper and lower heat transfer pipes connected to each other to form a fluid. The high and low temperature inlet (48, 39) to enter the U-turn, characterized in that the structure consisting of the other high and low temperature outlet (38,49), characterized in that the upper, lower heat pipes (99, 88) It is supported by the baffle 87 in the shell 10, the working fluid in the shell 10 is characterized in that any one of the freon gas, methanol, alcohol

Other structural features and configurations other than those described above will be described in detail below with the accompanying drawings.

First, the operation principle of the thermosiphon heat pipe according to the present invention is as follows.

Thermosiphon heat pipe is a wick (wick) structure, the heating part is located at the bottom, the condensation part is located at the top so that the return of the working fluid condensed at the top is returned by gravity.

As shown in Fig. 2, the evaporator is located below the condenser and there is no wick structure, so the heat flow rate is increased by 10 to 100 times than the wick type heat pipe on the left figure, and in capillary type, it is difficult to enter the liquid into the wick by boiling bubbles. However, in the thermosiphon type, boiling can be effectively used, and since there is no wick in the condensation part, there is an advantage that the thermal resistance is very small.

The working fluid in the thermosiphon heat pipe absorbs heat from the evaporator and evaporates, rises to the upper condenser by pressure and density difference, releases latent heat and condenses and returns liquid by gravity. By repeating, heat is transported. Therefore, the minimum amount of working fluid injection is enough to wet the inner surface area of the evaporator and the condensation part, and as the amount of heat transport increases, the amount of working fluid in contact with the inner surface also increases. However, when too much working fluid is injected, a thick liquid layer forms in the evaporation section and the liquid rises up to the condensation section, increasing the thermal resistance. If too little is injected, the liquid may not come into contact with the inner surface of the evaporation section. It is undesirable because dry-out occurs and the temperature rises rapidly, resulting in unstable operation and eventually damage.

Hereinafter, the structure of the thermosiphon type heat pipe heat exchanger according to the present invention will be described.

As illustrated in FIG. 3A, one side of the shell 10 has a low temperature import port 9 and a high temperature import port 8, and a low temperature export port 19 and a high temperature export port 18 are formed on the opposite side. In the meantime, upper and lower heat transfer tubes 99 and 88 are installed. The heat pipes are supported inside the shell 10 by the baffles 8.

A fixed tube plate 40 is formed integrally with the shell 10 on both sides of the shell 10, and the bonnet 4 is detachably coupled to the fixed tube plate 40.

Reference numeral 5 denotes a check valve for the vacuum inside the shell 10.

3B is a cross-sectional view of the bonnet, and FIG. 3C is a cross-sectional view of the fixed tube plate.

As shown, the bonnet 4 is provided with a low temperature import port 9 and a high temperature import port 8, and partition walls 44 are provided between the upper and lower portions thereof.

The partition wall 44 is also formed in the fixed tube plate 40 shown in FIG. 3C, and the upper heat exchanger tube 99 and the lower heat exchanger tube 88 are provided above and below. High temperature water flows through the lower heat exchanger tube 88, and low temperature water flows linearly through the upper heat exchanger tube 99.

In the description of the present invention will be described limited to hot water, of course, other fluids may also be used

The reason for the installation of the partition wall 44 is that when the fluid entering through the low temperature inlet 9 and the high temperature inlet 8 is distributed to the upper and lower heat transfer tubes 99 and 88 composed of a plurality of tubes, the high temperature water is used. And low temperature water to prevent mutual mixing

Reference numeral 41 is a fastening hole capable of coupling or dismounting the bonnet 4 to the fixed tube plate 40.

As the working fluid filled in the shell 10, for example, Freon gas was used, and the working fluid filling amount is preferably such that the entire amount of the lower heat transfer tubes 88 which are the evaporation parts can be contacted.

The above structure is made by connecting a vacuum system and vacuuming for a predetermined time, and then sealing and sealing a certain amount of a working fluid (such as freon gas, alcohol, methanol, etc.).

The operation by the above configuration will be described.

When the fluid enters through the inlet of the cold water and the hot water, respectively, the fluid passes through the bonnet 4 and the fixed tube plate 40. A partition wall 44 is installed in the longitudinal transverse path therethrough so that the respective fluids do not mix. It flows to the upper heat pipe 99 and the lower heat pipe (88).

In this case, the heat exchange mechanism is the same as that of the thermosiphon heat pipe.

That is, when hot water flows in, heat is transferred to the working fluid filled in the shell 10 through the lower heat transfer tube 88 so that the working fluid is boiled. At the same time, since the low temperature water flows into the upper heat pipe 99, when the boiling working fluid contacts the upper heat pipe, heat exchange with the low temperature water causes the working fluid to condense and flow downward toward the heat exchanger by gravity to boil and condense inside the shell 10. Will transfer heat while repeating

4a, 4b, 4c are other embodiments corresponding to the preceding FIGS. 3a, 3b, 3c.

This embodiment is made of a two-pass structure to further improve the heat transfer performance of the one-pass heat exchanger operating as described above.

In the present embodiment, the low temperature import port 39 and the low temperature export port 49 are formed on one side of the shell 10, and the high temperature import port 48 and the high temperature export port 38 are formed on the lower side thereof. That is, the low temperature water entering through the low temperature water inlet 39 is configured to go back along the upper heat pipe 99 bent in a U shape after going straight to the upper heat pipe 99 in the shell 10. The same applies to the configuration of the lower heat transfer pipe 88. And in addition to the partition wall 44, the vertical wall 45 was formed in the bonnet 4 and the fixed tube plate 40.

This two-pass structure is more excellent in heat transfer efficiency than the previous embodiment.

The heat exchanger having the 1,2-pass structure described above is merely an example. In addition, the heat transfer tube inserted into the shell 10 may be a corrugated tube, an inner pin, and a spiral tube to improve the heat transfer efficiency.

According to the heat exchanger according to the present invention described above, first, there is no need for tube arrangement using shell-side steam distribution and tube arrangement for discharging condensate, and second, no sub cooling zone of the existing condenser is needed, and third, exhaust Fourth, there is no concern about the congestion of steam, fourth, there is no vibration of the heat pipe due to the incoming steam, and fifth, it can solve some hunting problems at the start.

Claims (4)

A shell 10 having a working fluid filled therein, It is installed in the shell 10 is filled with the working fluid, the lower heat pipe 88 and the high temperature fluid flows therein, An upper heat transfer tube 99 installed above the lower heat transfer tube 88 and having a low temperature fluid flowing therein; Bonnet (4) formed on the side of the shell 10, having a high temperature inlet for the inlet of high temperature fluid and a low temperature inlet for the inlet of low temperature fluid, The thermosiphon heat pipe type heat exchanger is formed integrally with the side of the shell 10 and comprises a fixed tube plate 40 coupled to the bonnet 4. The method of claim 1, A thermosiphon heat pipe type heat exchanger, which is distinguished by the partition wall 44 between the bonnet 4 and the fixed tube plate 4, and is configured such that fluids having different temperatures do not enter each other. The method of claim 1, The bonnet 4 has a low temperature import, an outlet 39, 49 and a high temperature import, an outlet 48, 38, the partition wall 44 and the vertical wall 45 between the upper and lower heat transfer pipes connected thereto. The thermosiphon heat pipe type heat exchanger, characterized in that the fluid is formed into a high, low temperature inlet (48,39), U-turn, the other high, low temperature outlet (38, 49) The method of claim 1, The upper and lower heat transfer tubes 99 and 88 are supported by the baffles 87 in the shell 10, and the working fluid in the shell 10 is any one of freon gas, methanol, and alcohol. Thermosiphon Heat Pipe Type Heat Exchanger