JP2006084047A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger capable of improving heat exchanging efficiency and providing stable cooling by equally supplying ice slurry to each of cooling coils, and surely utilizing melting latent heat of ice in the ice slurry for cooling. <P>SOLUTION: In this heat exchanger 1 wherein a number of cooling coils 2, 2 are arranged in parallel between an inlet header 3 and an outlet header 4, and the ice slurry as ice water including small pieces of ice is distributed to the cooling coils 2, 2 from the inlet header 3 to supply cold heat of the ice slurry to the fluid outside of the coils, and discharged to the outside through the outlet header 4. The inlet header 3 has the cylindrical shape, comprises an inlet 3a of the ice slurry and a plurality of outlets 3b, 3b as connection ports with the cooling coils in the longitudinal direction, and is constituted in such a manner that the longer a distance from the ice slurry inlet is, the smaller a cross-sectional area of a flow channel of the header is. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat exchanger for cooling a fluid such as air or water using ice water as a cold heat source.

A cooling system that sends ice slurry to a heat exchanger as a cold heat source and uses it for air conditioning or the like has been conventionally used to supply cold heat from, for example, an ice heat storage device to the load side (see, for example, Patent Document 1 or 2). .
The ice slurry is a so-called sherbet-like ice water containing fine ice pieces in water or brine (antifreeze), and the fine ice produced by a scraping-type ice making machine is mixed with water in a water tank, for example. The ice slurry is generated by adjusting the required ice abundance ratio (IPF) or by releasing the supercooled water once it has been cooled to generate fine ice fragments in the water. The cooling system as a source has the merit that latent heat can be used in addition to sensible heat of water.

  As described above, in a cooling system using ice slurry as a cooling source, if the ice slurry melts and the sensible heat rises, the temperature difference with the fluid to be cooled such as air becomes small and the heat exchange efficiency decreases. The latent heat of the heat exchanger must be sufficiently consumed in the heat exchanger, and ice slurry must be supplied uniformly to the multiple cooling coils of the heat exchanger in order to sufficiently consume the latent heat.

  By the way, in the heat exchanger that flows liquid into the coil and uses it as a cooling heat source, a large number of cooling coils with almost equal pressure loss are provided in parallel between the straight cylindrical inlet header and outlet header, If it does in this way, a liquid will flow into each cooling coil equally.

  However, when ice slurry is circulated through the cooling coils, there is a bias in the ice content of the ice slurry that flows through each cooling coil, so that ice remains at the coil exit in the cooling coil where the ice content is high, and sufficient latent heat is generated. There is a problem that a sensible heat rises in a cooling coil where consumption is not performed and ice content is low and heat exchange efficiency is lowered.

In addition, if the ice slurry does not flow smoothly from the inlet header to the cooling coil, ice may accumulate in the inlet header and the cooling coil inlet may be blocked.
In addition, as a technique for preventing the cooling coil inlet from being blocked by ice, an agitating mechanism is provided in the inlet header (see, for example, Patent Document 2), or a bypass pipe is provided between the inlet header and the outlet header. Has been proposed to control the flow rate of ice slurry flowing in the cooling coil by providing a flow control valve (see, for example, Patent Document 3), but a technique for uniformly circulating ice slurry to each cooling coil is proposed. Has not yet been established as a general-purpose technology.
Japanese Patent Laid-Open No. 10-332178 (pages 1 to 3, FIGS. 1 to 3) Japanese Unexamined Patent Publication No. 09-89315 (pages 1-5, FIGS. 1-6) Japanese Patent Laid-Open No. 11-108383 (pages 1 to 4, FIGS. 1 to 5)

  In the present invention, the ice slurry is evenly supplied to each cooling coil, the latent heat of melting of the ice in the ice slurry can be reliably used for cooling, and the heat exchange efficiency is high and stable cooling can be performed. The challenge is to provide an exchange.

  The inventors have conducted extensive research on the above-mentioned problem that the ice slurry is not evenly distributed to the cooling coils, that is, the IPF in each cooling coil is different. As a result, when the flow rate of the ice slurry flowing in the inlet header decreases, the ice slurry is reduced. The ice inside the cooling coil is less likely to flow into the cooling coil, so the ice slurry flowing into the cooling coil connected to the vicinity of the ice slurry inlet of the inlet header has a large IPF, but cools as it moves away from the ice slurry inlet of the inlet header. The ice slurry that flows into the coil becomes smaller in IPF as the flow velocity decreases, and further, the ice that could not flow into the cooling coil in the middle flows into the cooling coil farthest from the ice slurry inlet, and the IPF of this cooling coil becomes smaller. If the IPF of the ice slurry flowing into the inlet header is larger or larger, the ice is the most from the ice slurry inlet. It was also found that accumulated in the cooling coil inlet near that or impede the flow of ice slurry into the coil.

  Therefore, the IPF of each cooling coil can be made equal by setting the flow rate of the ice slurry at the inlet portion of each cooling coil in the inlet header to a certain level or more.

  Thus, in the heat exchanger according to the present invention, a large number of cooling coils are provided in parallel between the inlet header and the outlet header, and ice slurry, which is ice water including ice strips, is distributed from the inlet header to each cooling coil. In the heat exchanger that supplies ice slurry cold heat to the fluid outside the coil and is sent to the outside via the outlet header, the inlet header is formed into a cylindrical shape, and the inlet of the ice slurry is connected to each cooling coil in the longitudinal direction. A plurality of outlets serving as mouths are provided, and the flow path cross-sectional area of the header is reduced as the distance from the ice slurry inlet increases.

  In addition, the inlet header is configured such that an ice slurry inlet is provided on one end side, and the flow path cross-sectional area decreases gradually or stepwise toward the other end.

  In the heat exchanger according to the present invention, the flow rate decreases because the ice slurry in the inlet header branches and flows into the cooling coil as it moves away from the vicinity of the ice slurry inlet, but the flow rate decreases because the cross-sectional area of the flow path becomes small. Maintained.

Therefore, even if the distance from the ice slurry inlet is different, the ice slurry flow velocity at the inlet portion of each cooling coil is substantially constant, so that the ice slurry flowing into each cooling coil has the same IPF, and the ice in each cooling coil is the same. The latent heat of melting of ice in the slurry can be fully utilized, and the heat exchange efficiency can be improved.

In addition, since the heat exchanger of the present invention is characterized by the shape of the inlet header, the configuration other than the inlet header portion of an existing general heat exchanger can be used as it is, and is manufactured at a low cost. There is also an advantage that you can.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the apparatus according to the present invention will be described below in detail based on specific examples shown in the accompanying drawings.
The heat exchanger main body 1 has a large number of heat radiation fins 10 and 10 that are penetrated by a large number of straight tubes 2a in parallel, and the ends of adjacent tubes are connected by a U-shaped bend tube 2b. Thus, the cooling coil 2 is configured.

  Each inlet of the cooling coil 2 is connected to a number of outlets 3 b of the inlet header 3, and each outlet of the cooling coil is connected to a number of inlets 4 b of the outlet header 4.

  Each of the inlet header 3 and the outlet header 4 has an inlet 3a and an outlet 4a for ice slurry near the lower end, and each header is formed of a cylinder whose upper and lower ends are closed.

  Thus, although the outlet header 4 is configured in a straight cylindrical shape, the inlet header 3 is configured in a shape in which the flow path cross-sectional area of the upper half is gradually reduced. In the upper half of the side opposite to the side where many outlets are provided, a side surface oblique to the central axis of the inlet header is provided, and the ice slurry outlets 3b and 3b are arranged in a line in the vertical direction. It is arranged.

  Accordingly, the flow rate of the ice slurry flowing into the inlet header 3 decreases due to the branching flow into the cooling coil from the lower part in the vicinity of the inlet 3a toward the upper end, but the cross-sectional area of the flow path becomes smaller upward. Is maintained above a certain level, so that the ice slurry flow rate at the inlet portion of each cooling coil 2 and 2 does not vary so much, so that the IPF of the ice slurry flowing into each cooling coil 2 and 2 becomes almost equal. Also in the cooling coil, the latent heat of melting of the ice slurry inside the coil is sufficiently and stably transmitted to a fluid such as air flowing outside the coil, and the heat exchange efficiency can be improved.

  The inlet header 3 in the above-described embodiment is configured so that the flow passage cross-sectional area gradually decreases as it moves away from the ice slurry inlet, that is, upwards. In some cases, for example, an inlet header 5 shown in FIG. 3 is provided with a medium diameter portion 7 and a small diameter portion 8 in this order, followed by a large diameter portion 6 having an ice slurry inlet 5a. Connections are made at the transition units 9 and 9, respectively.

In the case of this embodiment as well, the sides having the outlets 5b and 5b serving as connection ports with the cooling coils are arranged in a line in the vertical direction (vertical direction).
The inlet header 5 in the above embodiment is configured so that the flow passage cross-sectional area changes in three stages, but may be configured in two stages or four or more stages depending on the specifications of the heat exchanger.

The front view which shows the Example of the heat exchanger which concerns on this invention. The side view which shows the Example of the heat exchanger which concerns on this invention. (A) which shows the other example of an inlet header is a front view, (b) is a side view.

Explanation of symbols

1 Heat exchanger body
2 Cooling coil
3 Entrance header
4 Exit header
5 Entrance header
6 Large diameter part
7 Medium diameter part
8 Small diameter part
9 Transition Department

Claims (3)

  A number of cooling coils are provided in parallel between the inlet header and the outlet header, and ice slurry, which is ice water containing ice strips, is distributed from the inlet header to each cooling coil to supply ice slurry to the fluid outside the coil. In the heat exchanger sent to the outside through the outlet header, the inlet header is formed in a cylindrical shape and includes a plurality of outlets serving as connection ports between the inlets of the ice slurry and the cooling coils in the longitudinal direction. A heat exchanger configured such that the flow path cross-sectional area of the header decreases as the distance from the inlet increases.   2. The heat exchanger according to claim 1, wherein the inlet header is configured such that an ice slurry inlet is provided on one end side and the flow path cross-sectional area gradually decreases toward the other end.   2. The heat exchanger according to claim 1, wherein the inlet header is configured such that an ice slurry inlet is provided on one end side, and the flow path cross-sectional area gradually decreases toward the other end.

Images