JP4151928B2 - Water heat exchanger - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat exchanger that performs heat exchange between a refrigerant and water, and more particularly to a chiller water heat exchanger.
[0002]
[Prior art and its problems]
An example of a conventional water heat exchanger is shown in FIGS.
The refrigerant 1 enters the inflow chamber 5 through the refrigerant inlet pipe 3, flows into the return chamber 9 through the plurality of refrigerant forward pipes 7 in the shell 23, and is further returned through the refrigerant return pipe 11 to be outflow chamber. 13 flows out of the refrigerant outlet pipe 15.
[0003]
On the other hand, the water 19 flows into the shell 23 from the water inlet pipe 21, flows through the zigzag channel formed by the plurality of baffle plates 25, flows out of the water outlet pipe 27, and the water 19 flows into the zigzag. Heat exchange is performed with the refrigerant 1.
[0004]
Therefore, in the conventional water heat exchanger, as shown in FIG. 5, a water inlet pipe 21 and a water outlet pipe 27 are provided horizontally on the side of the shell 23, and water is fed into the shell from the side.
[0005]
In the above-described conventional water heat exchanger, there is a stagnation area 29 where the water flow is stagnant and vortices are likely to be formed on the downstream side of the baffle plate 25 base and in the vicinity of the communication part of the water inlet pipe 21. In the stagnation area 29, on the upstream side of the refrigerant outflow pipe 7 through which the low-temperature refrigerant passes, the water in the stagnation area 29 is excessively cooled and easily frozen, and when the frozen ice grows, the function as a water heat exchanger decreases. .
[0006]
OBJECT OF THE INVENTION
An object of the present invention is to provide a water heat exchanger capable of preventing freezing of water inside the shell.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the hydrothermal exchanger according to the present invention is provided in a shell in which both left and right ends are closed with tube plates, and a refrigerant forward pipe and a return pipe are arranged in parallel in the left and right directions. An upward baffle plate having a communication portion at the upper portion and a downward baffle plate having a communication portion at the lower portion are alternately provided in the left-right direction in the shell, and a water inlet pipe and an outlet pipe are provided on the left and right of the shell lower portion, and In the baffle plate, a water circulation hole is provided at the lower part of the upward baffle plate located at least upstream of the refrigerant in the refrigerant forward pipe.
[0008]
【Example】
Embodiments of the water heat exchanger according to the present invention will be described below based on specific examples shown in FIGS.
As shown in FIGS. 1 and 2, the water heat exchanger of this embodiment has a cylindrical shell 23 whose left and right ends are respectively closed by tube plates 35 and 35, and the shell 23 has an axial direction of the shell. A large number of refrigerant outgoing pipes 7 and refrigerant return pipes 11 are arranged (in the left-right direction), and the shell 23 is supported by legs 33.
[0009]
The left and right tube plates 35, 35 are provided with end chambers 37, 9 closed by end plates 37a, 9a, respectively, and the left end chamber 37 is divided into two chambers by a partition plate 41 in the vertical direction. Forms the inflow chamber 5, the upper chamber forms the outflow chamber 13, and the right end chamber 9 is the return chamber.
[0010]
The end plate 37a of the left end chamber is provided with a refrigerant inlet pipe 3 that communicates with the inflow chamber 5 and a refrigerant outlet pipe 15 that communicates with the outflow chamber 13, and a water inlet pipe 21 at the lower portion on the left end side of the shell 23. Is provided in the vertical direction, and a water outlet pipe 27 is provided vertically in the lower part on the right end side.
[0011]
A plurality of baffle plates are provided inside the shell 23, and these baffle plates are divided into an upward baffle plate 25A having a communication portion 25a in the upper portion and a downward baffle plate 25B having a communication portion 25b in the lower portion. An upward baffle plate 25A and a downward baffle plate 25B are alternately arranged from the middle left end toward the right end to form a water flow path in a zigzag manner up and down. 7 and the refrigerant return pipe 11 pass therethrough.
[0012]
The baffle plates 25A and 25B are supported at the left end by the support rod 12 fixed to the left tube plate 35, and the adjacent baffle plates are kept at a predetermined interval by the spacer tubes 14 and 14 fitted to the support rod. Yes.
The support rod is made of, for example, a screw rod, and a baffle plate is held by fitting a nut 16 at the right end.
[0013]
Therefore, in the upward baffle plate 25A, the portion provided on the uppermost stream side of the refrigerant forward pipe 7, that is, the left end portion in the figure, has a through hole 43 for water circulation near the lower wall surface.
[0014]
In the water heat exchanger having the above configuration, the refrigerant sent from the refrigerant inlet pipe 3 through the inflow chamber 5 to the refrigerant forward pipe 7 exchanges heat with the water 19 in the shell 23, and the refrigerant from above the return chamber 9 The refrigerant enters the return pipe 11, and also in the refrigerant return pipe, heat is exchanged with water and is sent to the outflow chamber 13 and flows out from the refrigerant outlet pipe 15 to the outside.
[0015]
On the other hand, the water 19 is sent from the water inlet pipe 21 into the shell 23 from the bottom to the top, and is led to the baffle plates 25A and 25B in which the plurality of communication portions 25a and 25b are alternately turned upside down, and is formed in a zigzag shape. Turbulent flow occurs, and heat exchange with the refrigerant passing through the refrigerant forward pipe 7 and the refrigerant return pipe 11 is sufficiently performed.
[0016]
Moreover, since a part of the water fed into the shell passes through the through hole 43 formed in the base portion of the upward baffle plate 25A on the left end in the figure, the water does not stagnate around the base portion of the baffle plate 25A.
[0017]
When R407C having an evaporation temperature of 0 to −18 ° C. is used as the refrigerant, the inlet temperature of water is 13 to 5 ° C., and the outlet temperature is 7 to 2 ° C., the evaporation temperature of the refrigerant is immediately removed by heat exchange with water. When the heat exchange continues, the temperature rises and becomes superheated steam.
[0018]
Therefore, by connecting the water inlet pipe 21 directly below the shell 23, a stagnation region of water is generated near the upper wall surface of the tube plate 35 above the inside of the shell 23 which is the back side of the water inlet pipe 21. Most of the refrigerant passing through the refrigerant return pipe 11 in the stagnation area is warmed superheated steam, so that there is almost no possibility of water freezing.
[0019]
Furthermore, although the low temperature from the inflow chamber 5 passes through the refrigerant forward pipe 7, it is relatively uncooled that has just flowed into the shell from the water inlet pipe 21 at the most upstream side of the refrigerant forward pipe 7. Since water with high temperature flows, there is no possibility that the water will freeze.
[0020]
Further, since the through hole 43 is formed in the baffle plate 25A on the most upstream side, no stagnation area is formed in the lower portion of the baffle plate 25A, and therefore there is no possibility of freezing.
[0021]
Therefore, freezing of water in the shell is prevented even when a refrigerant having a large temperature gradient is used, such as an R407 refrigerant.
[0022]
In the embodiment described above, the through-hole 43 formed in the baffle plate is formed only in the lower part of the uppermost baffle plate 25A on the most upstream side, but may be formed in the other upward baffle plate 25A.
[0023]
Further, instead of providing the return chamber 9 at the end of the shell 23, the return chamber 9 may be omitted by connecting the refrigerant forward pipe 7 and the refrigerant return pipe 11 with a bend pipe or a header.
Furthermore, although the case where R407C was used as a refrigerant | coolant was demonstrated, it is also possible to use another refrigerant | coolant.
[0024]
【The invention's effect】
As described above, according to the present invention, the water inlet pipe is communicated with the lower part of the shell, so that it is not cooled in the most upstream part of the refrigerant forward pipe, that is, the part through which the coldest refrigerant passes. Water having a relatively high temperature can be fed, and a stagnation region of water can be made difficult to occur in that portion, so that freezing of water can be prevented.
[0025]
Further, among the upward baffle plates projecting upward from the lower wall surface inside the shell, a through hole is formed in at least the lowermost portion of the refrigerant located on the most upstream side of the refrigerant flowing through the refrigerant forward pipe, that is, the lowest temperature portion. Therefore, the stagnation of water at the base part on the back side of the baffle plate can be eliminated, and therefore, freezing of water at the base part of the baffle plate can be prevented.
[Brief description of the drawings]
FIG. 1 is a partially cutaway front view showing an embodiment of a water heat exchanger according to the present invention.
FIG. 2 is a partially broken plan view of the water heat exchanger.
3A is a left side view of FIG. 1, FIG. 3B is a longitudinal sectional view taken along the line B-B, FIG. 3C is a longitudinal sectional view taken along the line C-C, and FIG. FIG.
FIG. 4 is an enlarged longitudinal front view showing a baffle plate support structure.
FIG. 5 is a front view of a conventional water heat exchanger with a part thereof broken away.
FIG. 6 is a left side view of the water heat exchanger.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 3 Refrigerant inlet 5 Inflow chamber 7 Refrigerant outbound pipe 9 Return chamber 11 Refrigerant return pipe 13 Outflow chamber 15 Refrigerant outlet 21 Water inlet pipe 23 Shell 25A Upward baffle plate 25B Downward baffle plate 25a Communication part 25b Communication part 27 Water outlet pipe 29 Stagnation area 35 Tube plate 39 End plate 43 Through hole

Claims (1)

An upward baffle plate with a communication part at the top and a downward direction with a communication part at the bottom in a shell in which both left and right ends are blocked by tube plates, Baffle plates are provided alternately in the left-right direction in the shell, water inlet pipes and outlet pipes are provided on the left and right of the shell lower part, and the upward baffle located at least upstream of the refrigerant in the refrigerant forward pipe in the baffle plate A water heat exchanger in which a through hole for water flow is provided at the bottom of the plate.

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