SU1739175A1 - Heat exchanger - Google Patents

Abstract

The invention relates to refrigeration engineering, in particular to the creation of heat-exchanging apparatuses for cooling a stream of moist air. The aim of the invention is to increase the efficiency of the heat exchanger by eliminating frost on the pipes. The heat exchanger comprises a casing 1 with an inlet 2 and an outlet 3 collectors for the cooled gas. In the casing there is a bundle of heat exchange tubes 4 connected to the inlet 5 and outlet 6 collectors for the refrigerant. A portion of the pipes 4 of the peripheral row 7 in the sections 8 located opposite the inlet manifold 2 for the cooled gas has openings 9 and forms a device for protecting the pipes from frost formation. The holes 9 in the pipes 4 are located at equal distances from each other. 1 hp ff, 1 ill.

Description

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The invention relates to refrigeration engineering, in particular to the creation of heat-exchanging apparatuses for cooling a stream of moist air.

Known heat exchanger (avt.St. No. 1326871, CL F 28 G 15/00), containing in the annular space a hollow false tube plate, divided into two sections, the cavity of which is connected to a source of compressed air. In the sections there are round-shaped cells covering the pipes with a gap and having annular shaped slots arranged at an angle to the axis of the pipes being cleaned. Compressed air, the exit from the gap, removes the pipe formation by injections, and due to the reactive force, the tube plate moves inside the heat exchanger.

The disadvantages of the heat exchanger are the presence of moving parts and, as a result, its low operational reliability, large mass, and difficulty in manufacturing.

The closest to the proposed is a heat exchanger (ed. No. 1179081, cl. F 28 G 1/10), containing in the annular space additionally installed cleaning nozzles fixed on elastic elements.

The disadvantages of the known heat exchanger are low reliability of operation due to the presence of moving elements, a low intensification of the heat exchanger due to the impossibility of completely removing the formation of pipes from the walls, high mass, difficulty in manufacturing and selection of the characteristics of moving elements.

The aim of the invention is to increase the efficiency of the heat exchanger by eliminating frost on the pipes.

To do this, in a heat exchanger containing a casing with inlet and outlet headers for the cooled gas, a bundle of heat exchange tubes connected to the inlet and outlet headers for the refrigerant, and a device for protecting pipes from frost formation on the tubes, part of the tubes of the peripheral row in areas opposite to the inlet manifold for the cooled gas, is made with openings directed towards this manifold, with the formation of a device for protecting pipes from frost formation. The holes in the pipes are located at the same distance from each other.

The drawing schematically shows the proposed heat exchanger.

The heat exchanger comprises a casing 1 with an inlet 2 and an outlet 3 collectors for the cooled gas. In the casing is placed a bundle of heat exchanger tubes 4 connected to

inlet 5 and outlet b refrigerant manifolds. A portion of the pipes 4 of the peripheral row in areas 8 located opposite the inlet manifold 2 for the cooled

gas, has holes 9 and forms a device to protect the pipes from frost formation. The holes 9 in the tubes are located at equal distances from each other.

The heat exchanger works as follows

in a way.

A stream of moist gas, such as air, through the inlet manifold 2 enters the bundle of heat exchange tubes 4, which are cooled by the refrigerant flowing into

pipes from the inlet manifold 5 for the refrigerant. For example, liquid nitrogen can be used as a refrigerant. Heat exchange between the gas and the refrigerant takes place through the pipe walls. A coolant is injected from the holes 9 towards the oncoming flow of moist gas, which evaporates in the stream and lowers the gas temperature below the crystallization temperature of the water. The flow rate of the refrigerant through the openings 9, which ensures complete freezing of moisture from the gas stream, is determined from the ratios of the heat balance. The uniform arrangement of the openings 9 on the part of the pipes 4 opposite the inlet manifold 2 for the cooled gas ensures uniform freezing of moisture over the cross-section of the gas stream. The fine ice crystals formed in the gas are carried away with dry gas through the annular space to the output collector 3, and are not deposited on the walls of the pipes 4 due to the low adhesion of the crystal to the low-temperature surface of the heat exchange pipe.

Thus, in the proposed heat exchanger, the frost formation on the pipes is eliminated, which leads to an intensification of heat exchange,

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Claims (2)

1. A heat exchanger comprising a housing with inlet and outlet manifolds for the cooled gas, a bundle of heat exchange tubes arranged therein, connected to the inlet and outlet manifolds for the refrigerant, and a device for protecting pipes from frost formation, characterized in that, in order to increase efficiency by eliminating pipe formation, part of the tubes of the peripheral row of the beam in the areas opposite the intake manifold for the cooled gas is made with openings directed towards this collector, with calling the said device. 2. A heat exchanger according to claim 1, wherein the apertures in the pipes are located at the same distance from each other.