JPH03140794A - Shell and tube type heat exchanger - Google Patents

Abstract

PURPOSE:To obtain a high-performance heat exchanger by a method wherein small diametral heat transfer tubes are arranged in the front half on the inlet side of medium flowing through the heat transfer tubes while large diametral heat transfer tubes are arranged in the rear half on the outlet side of the medium flowing through the same. CONSTITUTION:A vessel for fluid, which flows the outside of heat transfer tubes 1, 2, is formed of a tube plate 5, partitioning plates 3, heat transfer tubes 1, 2, penetrating through and fixed to the tube plate 5 and the partitioning plates 3, and a cylinder plate 4, enclosing these plates and tubes, while a heat exchanger is formed by attaching a lid plate 6, forming the passage of refrigerant in the heat transfer tubes on the tube plate 5. In this case, the heat transfer tubes 1 are provided with a small diameter and the heat transfer tubes 2 are provided with a large diameter. The refrigerant in the heat transfer tubes enters through an inlet port 7 in mixed gas and liquid condition, then, flows through the heat transfer tubes sequentially from the heat transfer tubes 1 to the heat transfer tubes 2 while effecting heat exchange between the fluid outside of the heat transfer tubes and becoming gaseous state, then, is discharged out of an outlet port 8. On the other hand, fluid outside of the heat transfer tubes enters from an entrance port 9 while effecting heat exchange between the refrigerant in the heat transfer tubes and meandering through a passage formed by the partitioning plates 3, then, is discharged out of another outlet port 10.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used in refrigerators such as chiller units, and has high performance and high reliability. The present invention relates to a structure suitable for obtaining a heat exchanger of high quality.

[Conventional technology]

A shell antch that has been commonly used.

-G type heat exchanger is [Refrigerating Mechanical Engineering Handzook JP,
869-87184 July 25, 12 reprint Hideo Uchida ■ Asakura Shoten, "Frozen Sky 114 Handbook JP', 250-251.
As stated in the Japan Refrigeration Association, reprinted June 80, 1965, it is common to use all heat transfer tubes of the same diameter, and the flow rate, performance, and lifespan of the fluid inside and outside the heat transfer tubes are generally the same. Various studies have been made regarding this.

[The problem that the invention aims to solve]

The above conventional technology does not take into consideration the dryness, flow rate, and optimization of heat transfer performance of the refrigerant inside the heat transfer tube, and also does not take into account the reliability caused by vibrations caused by the fluid outside the heat transfer tube. There was a problem.

An object of the present invention is to provide a heat exchanger with higher performance.

Another object of the present invention is to provide a more reliable heat exchanger.

[Means to solve the problem]

In order to achieve the above objective, the dryness of the refrigerant in the heat exchanger tubes is related to the dryness of the refrigerant in the heat exchanger tubes. Improve performance by reducing the diameter of the heat tube. In addition, in areas with high dryness (refrigeration outlet 4), the flow rate is high, but the pressure loss is also large, so the performance is improved by increasing the diameter of the heat transfer tube.

On the other hand, regarding the vibration of the fluid outside the heat exchanger tube of the heat exchanger, the portion where the interval between the partition plates is small can have a small outside flow velocity and a small deflection due to the small diameter heat exchanger tube. Ninth, in the part where the distance between the partition plates is large, the deflection can be reduced by using a large-diameter heat exchanger tube, and reliability can be improved.

[Effect]

In a shell-and-chape heat exchanger, the state of the refrigerant flowing inside the heat transfer tube is a gas-liquid mixture at the inlet, and the degree of dryness is low, and the flow rate is relatively slow and heat transfer performance is poor, resulting in poor heat transfer. Improve performance by reducing the pipe diameter and increasing the flow rate. In addition, the refrigerant outlet part is a gas and the flow rate is relatively high, but the pressure loss is large and the performance deteriorates, so the heat transfer diameter f is increased to reduce the pressure loss and improve the performance.

On the other hand, regarding the vibration of the rising fluid in the heat exchanger tubes, in the part where the distance between the partition plates is small, the passage area becomes large due to the small diameter heat transfer tube, so the flow velocity outside the tube is small, and the deflection should be reduced by /J%. Can be done. In addition, the deflection of the large-diameter heat exchanger tubes can be reduced in the parts where the partition plates are spaced widely, reducing receding and improving reliability.

By changing the diameter of the heat transfer tube as described above, it is possible to simultaneously improve performance and reliability.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

The shell plate 4 covers the outer periphery of the heat transfer tubes 1 and 2, which are fixedly passed through the tube plate 52 and the partition plate 8, to form a container for the heat transfer tube outside tIf. A heat exchanger is formed by attaching a cover plate 6 that forms a heat exchanger.

The heat transfer tube 1 has a small diameter, and the heat transfer u2 has a large diameter.The refrigerant in the heat transfer tube enters from the input lower in an air-g mixed state as shown by the broken line arrow, and flows through the heat transfer tubes in the order of heat transfer tube 1 and heat transfer tube 2. It exchanges heat with the external fluid, becomes gaseous, and exits from the outlet 8. On the other hand, the fluid outside the heat transfer tube exits from the inlet 9 through the outlet 10 while meandering through the passage of the partition plate 8 while exchanging heat with the refrigerant inside the heat transfer tube, as indicated by the solid arrow.

〔Effect of the invention〕

Since the present invention is configured as described above, it produces the effects described below.

Appropriate heat exchange conditions can be obtained for the refrigerant in the heat transfer tubes, resulting in a higher performance heat exchanger.

In addition, vibration of the heat exchanger tubes can be reduced and their lifespan can be improved, resulting in a more reliable heat exchanger A.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a shell-and-chape heat exchanger according to an embodiment of the present invention, and FIG. It is an arrow sectional view. ■...Heat transfer f (thin tube) 2...Heat transfer tube (thick tube) 8
...Partition plate 4...Body plate 5...Tube plate
7... Refrigerant inlet 8... Refrigerant outlet Coolant inlet
10... Cooled liquid outlet. 6... Lid 9... Cover

Claims (1)

[Claims] A body plate covers the outside of the heat exchanger tube fixed through the tube plate and the partition plate to form a container for the medium outside the heat exchanger tube, and a lid plate is attached to the outside of the tube plate to form a passage for the medium inside the heat exchanger tube. In the shell-and-tube heat exchanger, a small-diameter heat transfer tube is installed in the first half of the inlet side of the medium circulating in the heat transfer tubes, and a large-diameter heat transfer tube is installed in the second half of the outlet side of the medium circulating in the heat transfer tubes. A shell-and-tube heat exchanger featuring