JPH08159611A - Water cooled condenser - Google Patents

Abstract

(57) [Summary] [Structure] In the water-cooled shell-and-tube condenser 2 of a water-cooled refrigeration system, when designing a condenser having a large condensation capacity and a condenser having a small condensation capacity with the same inner diameter of the condenser body, In order to obtain the necessary condensing capacity, the heat transfer tubes 7 at the contact surface with the gas refrigerant are arranged so that the arrangement of the heat transfer tubes 8 in contact with the gas refrigerant in the vicinity of the partition that divides the cooling water passage becomes wavy.
Reduce the density of. [Effect] Liquid refrigerant liquid that is condensed and accumulated in the condenser by avoiding as much as possible the deterioration of heat exchange performance in the heat transfer pipe that comes into contact with the gas refrigerant due to the liquid refrigerant that is condensed by the heat transfer pipes arranged in the upper part and flows down. It is not necessary to make the surface high, and the amount of refrigerant enclosed can be reduced as compared with the conventional case.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a water-cooled refrigeration system.

[0002]

2. Description of the Related Art In the condenser described in Japanese Patent Laid-Open No. 4-116358, when a condenser having a large condensing capacity and a condenser having a small condensing capacity with the same inner diameter of the condenser body are designed, they are arranged in the upper part. How to thin out the heat transfer tubes that are in contact with the gas refrigerant in order to avoid the deterioration of heat exchange performance in the heat transfer tubes that are in contact with the gas refrigerant due to the liquid refrigerant that is condensed and flows down in the heat transfer tubes and obtain the necessary condensation capacity. Then, there was a problem that it is best to arrange them. In addition, since the lowering of the performance is compensated by the heat transfer tube in the lower part that is submerged in the liquid refrigerant that supercools the refrigerant by increasing the liquid surface of the liquid refrigerant that is condensed and accumulated in the condenser, the amount of refrigerant to be filled must be increased. I had to do it.

[0003]

In the conventional water-cooled shell-and-tube condenser of the water-cooled refrigeration system, when a plurality of independent refrigerating cycles share a common cooling water passage on the exhaust heat side, the external dimensions are restricted. A plurality of condensers that are short in the longitudinal direction and thick in the circumferential direction are combined in series to form a refrigeration system. In this type of condenser, in order to secure the heat transfer area and suppress the increase in the water speed of the exhaust heat side cooling water by shortening it in the longitudinal direction and thickening it in the circumferential direction due to the restrictions on the external dimensions, The number of heat tubes will increase,
Along with this, the number of stages of heat transfer tubes also increases. At this time, the heat exchange performance of the heat transfer tubes arranged in the lower part is that the liquid refrigerant condensed and flowed down in the heat transfer tubes arranged in the upper part covers the outer surface and the thickness of the liquid film increases, so Compared with the case where there is no influence, it will be reduced to 60 to 90% depending on the outer surface shape of the heat transfer tube and the amount of liquid refrigerant flowing down.
Therefore, heat exchange in the heat transfer tube in contact with the gas refrigerant is repeated on the outer surface of the heat transfer tube from the upper part of the condenser,
As it moves to the lower heat transfer tube, the amount of the condensed liquid flowing down to the outer surface of the heat transfer tube also increases, and the heat exchange performance of the entire condenser deteriorates significantly. For this reason, when designing a condenser with a large condensing capacity and a condenser with a small condensing capacity by making the inner diameter of the condenser body the same, the transfer of the liquid refrigerant that is condensed by the heat transfer tubes arranged in the upper part and is in contact with the gas refrigerant. In order to avoid the deterioration of heat exchange performance in the heat tube as much as possible and to obtain the necessary condensing capacity, how to thin out the heat transfer tube that is in contact with the gas refrigerant,
There was a problem whether it was best to arrange them. In addition, the amount of reduced performance is increased by increasing the liquid level of the liquid refrigerant that is condensed and accumulated in the condenser, and the lower heat transfer tube that is immersed in the liquid refrigerant that supercools the refrigerant compensates for the decreased performance. There was a problem that it had to be increased.

According to the present invention, when a condenser having a large condensing capacity and a condenser having a small condensing capacity with the same inner diameter of the condenser body are designed, a partitioning section for dividing the cooling water passage is obtained in order to obtain a necessary condensing capacity. By reducing the number of heat transfer tubes at the contact surface with the gas refrigerant so that the heat transfer tube arrangement that is in contact with the nearby gas refrigerant has a wavy shape, the liquid refrigerant that is condensed and flows down by the heat transfer tubes arranged in the upper part It is to avoid the deterioration of the heat exchange performance in the heat transfer tube that comes into contact with the gas refrigerant as much as possible. In addition, by preventing the performance deterioration, the liquid level of the liquid refrigerant that is condensed and accumulated in the condenser is raised, and it is not necessary to supplement the performance deterioration with the lower heat transfer tube that is immersed in the liquid refrigerant that supercools the refrigerant. Therefore, it becomes possible to reduce the amount of refrigerant to be filled in as compared with the conventional case.

[0005]

In the water-cooled shell-and-tube condenser, when a condenser having a large condensing capacity and a condenser having a same condensing body inner diameter and a small condensing capacity are designed, a cooling water passage is provided. So that the arrangement of the heat transfer tubes in contact with the gas refrigerant near the partition that divides the
This is achieved by reducing the heat transfer tube density at the contact surface with the gas refrigerant.

[0006]

[Operation] Compressor, water-cooled shell and tube condenser,
In a water-cooled refrigeration system with a refrigeration cycle consisting of a water cooler and an expansion valve, when designing a condenser with a large condensation capacity and a condenser with a small condensation capacity with the same inner diameter of the condenser body, the required condensation capacity In order to obtain the above, the number of heat transfer tubes at the contact surface with the gas refrigerant is reduced so that the heat transfer tube arrangement in contact with the gas refrigerant in the vicinity of the partition section that divides the cooling water passage has a wavy shape. As a result, the heat exchange performance of the heat transfer tubes that are in contact with the gas refrigerant due to the liquid refrigerant that is condensed and flows down by the heat transfer tubes arranged above is avoided. Therefore,
By preventing this performance deterioration, the liquid surface of the liquid refrigerant that is condensed and accumulated in the condenser is raised, and there is no need to compensate for the performance deterioration with the lower heat transfer tube that is immersed in the liquid refrigerant that supercools the refrigerant. It is possible to further reduce the amount of refrigerant enclosed. Further, the cooling water passage on the exhaust heat side has two passages that flow in from the end of the condenser, pass through the inside of the condenser, and return at the end on the opposite side to pass through the inside of the condenser again and flow out. Since the number of heat transfer tubes near the partition that divides the cooling water passage is reduced to a corrugated shape, the number of heat transfer tubes per passage is the same, and the balance of heat exchange performance per passage is maintained.

[0007]

EXAMPLE An example of the present invention will be described below.

FIG. 1 is a block diagram of a water-cooled refrigerating apparatus for carrying out the present invention.

FIG. 2 is a sectional view of the water-cooled shell-and-tube condenser of the present invention.

The structure is a refrigeration cycle consisting of a compressor 1, a water-cooled shell-and-tube condenser 2, an expansion valve 3, and a water-cooler 4. The water-cooled shell-and-tube condenser 2 is shown in detail in FIG. The structure is as shown in the sectional view.

The high-temperature high-pressure gas refrigerant compressed by the compressor 1 flows into the condenser through the refrigerant inlet 5. This gas refrigerant exchanges heat with the heat transfer tubes 6 arranged in the upper part, is condensed and drops. The dropped liquid refrigerant reaches the liquid surface 9 of the liquid refrigerant while being transmitted through the heat transfer tubes 7 arranged in the central portion. Then, the liquid refrigerant accumulated in the lower part of the condenser flows out from the refrigerant outlet 10, passes through the expansion valve 3, flows into the water cooler 4, and enters the compressor 1
Return to.

According to the present invention, when a condenser having a large condensing capacity and a condenser having a small condensing capacity with the same inner diameter of the condenser body are designed, the cooling water passages are divided in order to obtain a necessary condensing capacity. Liquid that is condensed and flows down by the heat transfer tubes arranged in the upper part by reducing the density of the heat transfer tubes at the contact surface with the gas refrigerant so that the heat transfer tube arrangement in contact with the gas refrigerant near the partition becomes wavy. It is possible to avoid a decrease in heat exchange performance in the heat transfer tube that comes into contact with the gas refrigerant due to the refrigerant. In addition, by preventing the performance deterioration, the liquid level of the liquid refrigerant that is condensed and accumulated in the condenser is raised, and it is not necessary to supplement the performance deterioration with the lower heat transfer tube that is immersed in the liquid refrigerant that supercools the refrigerant. Therefore, it becomes possible to reduce the amount of refrigerant to be filled in as compared with the conventional case.

[0013]

According to the present invention, when designing a condenser having a large condensing capacity and a condenser having a small condensing capacity with the same inner diameter of the condenser body, a cooling water passage is provided to obtain a necessary condensing capacity. By reducing the number of heat transfer tubes at the contact surface with the gas refrigerant so that the heat transfer tube arrangement that is in contact with the gas refrigerant near the partitioning section becomes wavy, it is condensed by the heat transfer tubes arranged above and flows down. The deterioration of the heat exchange performance in the heat transfer tube in contact with the gas refrigerant due to the liquid refrigerant is prevented as much as possible. Also, by preventing the performance degradation, the liquid surface of the liquid refrigerant that is condensed and accumulated in the condenser is raised, and there is no need to supplement it with a heat transfer tube in the lower part that is immersed in the liquid refrigerant that supercools the refrigerant,
It is possible to reduce the amount of refrigerant enclosed as compared with the conventional case.

[Brief description of drawings]

FIG. 1 is a block diagram of a water-cooled refrigeration system embodying the present invention.

FIG. 2 is a sectional view of the water-cooled shell-and-tube condenser of the present invention.

[Explanation of symbols]

1 ... Compressor, 2 ... Water-cooled shell and tube condenser,
3 ... Expansion valve, 4 ... Water cooler, 5 ... Refrigerant inlet, 6, 7, 8
... Heat transfer tube, 9 ... Liquid level, 10 ... Refrigerant outlet.

Front Page Continuation (72) Inventor Tetsuo Shimoda 390 Muramatsu, Shimizu City, Shizuoka Prefecture, Hitachi, Ltd. Air Conditioning Systems Division

Claims (1)

[Claims] 1. A water-cooled shell-and-tube condenser of a water-cooled refrigeration system including a compressor, a condenser, a water cooler, and an expansion valve, wherein the condenser having a large condensing capacity and the condensing capacity of the condenser body have the same inner diameter. When designing a condenser with a small size, in order to obtain the necessary condensing capacity, the contact surface with the gas refrigerant must be arranged so that the heat transfer tube arrangement that is in contact with the gas refrigerant near the partition that divides the cooling water passage becomes wavy. A water-cooled shell-and-tube condenser characterized by a reduced heat transfer tube density.