RU2378595C1 - Heat exchanger - Google Patents

Abstract

FIELD: heating systems.

SUBSTANCE: invention refers to heat engineering and can be used during arrangement of high thermally stressed heat exchanger of nuclear power plant. In heat exchanger consisting of bank of heat exchange coil tubes the ends of which are fixed in tube sheets arranged in the form of a platen, straight sections of several coil tubes are located consequently in one plane, and bent sections are opened to the side from location plane of straight sections; at that, opening of bends of opposite ends, straight sections, is made to different sides.

EFFECT: providing maximum compactness of tube bank of heat exchanger and reaching high degree of heat exchange efficiency owing to arrangement of heat removal surface itself during operation, increasing life time of reliable operation of heat exchanger design at high specific thermal stresses of the volume occupied with it.

5 dwg

Description

The invention relates to a heat exchange technique and is intended for use as a small-sized heat exchanger in the composition of a high pressure separator-superheater (SPP) of a steam generating nuclear power plant (NPP) operating on a liquid metal coolant in the mode of variable loads.

A shell-and-tube heat exchanger is known with a bundle of screw-shaped tubes of shaped profile, made twisted relative to its longitudinal axis, with a relative twist of radius decreasing along the bundle radius and with straight pipe ends having a length equal to the diameter of the inlet and outlet nozzles with the formation of collectors for the annulus and porosity in the jacket , greater porosity of the swirling part of the beam [1].

The disadvantage of this technical solution is the relatively low intensity of heat transfer between the heating and heated liquids in the design of the heat exchanger as a whole and, as a result, the low values of the output steam content when used as a modular heat exchanger, for example, as part of a high-pressure SPP of a steam generating nuclear power plant.

A single-threaded tubular coil is known, mainly for the convective chamber of a tubular furnace, containing rows of straight pipes arranged in a checkerboard pattern and connected at the ends by bends with a bend angle of 180 °, and the extreme pipes of each row are equipped with additional bends, the axes of which are located in the row plane and the angle their bend is determined from the corresponding mathematical expression [2].

The disadvantage of this technical solution is the deterioration of the heat transfer process between heating and heated fluids with an increase in the depth of the tube bundle due to an increase in thermo-hydraulic resistance to the flow of the moving coolant and, as a consequence, a decrease in the resource of reliable operation of the structure, since the large temperature head between the inlet and outlet of the coolant leads to very significant damage at the contact points of the metal pipes and their supporting structures.

The technical result of the invention is to ensure maximum compactness of the tube bundle of the heat exchanger and to achieve a high degree of heat transfer efficiency due to the layout of the heat removal surface itself during operation, to increase the resource of reliable operation of the heat exchanger design at high specific heat voltages of the volume occupied by it.

The specified technical result is achieved by the fact that in the heat exchanger, consisting of a bundle of heat-exchange coil pipes, the ends of which are fixed in tube boards arranged in the form of a screen, the straight sections of several coil pipes are arranged sequentially in one plane, and the bent sections are divorced one side from the plane of location straight sections, and the layout of bends of opposite ends, straight sections, is made in different directions.

The information search of scientific and technical achievements on this topic, a thematic analysis of the inventions of the patent fund of VTBT to solve this problem did not reveal a combination of distinctive features similar (and inherent) with the features of the invention, which can be used as a small-sized heat exchanger in the composition of high-pressure SPP re-producing A nuclear power plant operating on a liquid metal coolant in the mode of variable loads. In accordance with the current legislation of Russia, the proposed invention meets the criteria of "novelty", "prior art", "industrial applicability".

The essence of the invention is illustrated by drawings, where:

figure 1 is a longitudinal section of a heat exchanger;

figure 2 is a cross section along aa;

figure 3 is a longitudinal section of a heat exchanger module;

figure 4 - shows a tube bundle;

figure 5 - shows a tube bundle with wiring bends.

The heat exchanger comprises a housing 0 with a lower (upper) cover 1, nozzles for the inlet 2 and outlet 3 of the heating medium, inlet 4 and outlet 5 of the pumped liquid (wet steam), all nozzles having a chamber 6 for distributing heat-exchanging liquids with a corresponding cover 7, tube boards 8 to which modular heat exchangers 9 are connected with nozzles 10 and 11, 12 and 13 by means of pipelines, and the modular heat exchangers 9 relative to the housing 0 are spaced apart by spacers 14. Each modular heat exchanger 9 has a camera 15 inlet and outlet 16 warmly Itel, the chamber of the inlet 17 and the outlet 18 of the heated fluid, while the chambers of the inlet 17 and the outlet 18 of the heated fluid have tube boards 19 and 20, respectively, to which the bundle of heat-exchange coil pipes 21 is attached, the inlet chambers 15 and the outlet of the coolant 16 have perforated tube boards 22 and 23, respectively.

The heat exchanger operates as follows.

The heating coolant enters through the nozzle 2 into the distribution chamber 6, from where it enters the nozzle 10 of the modular heat exchanger 9 through pipelines (not shown), into the distribution chamber 15 and through the perforation of the board 22 into the annulus of the bundle of heat-exchange coil pipes 21. Then, through the perforation of the board 23 into the chamber 16, from where it goes through the pipe 11 through the pipe 11 and through the pipe 3. The heated liquid (wet steam) enters through the pipe 4 to the distribution chamber 6, from where through pipelines (not shown) to the pipe 12 of the modular heat exchanger 9, then to dispensing measure 17 enters the cavity of the tube bundle of heat exchange tubes coils 21 in chamber 18, whence through the pipe 13 by pipeline 6 into the chamber and exits through pipe 5.

The design of the heat exchanger of the proposed type will make it possible to use it as a modular heat exchanger with the most compact bundle of heat exchange coil tubes of a steam generating ship nuclear power plant operating on a liquid metal coolant in variable load conditions that meet the requirements of reliability, manufacturability, installation, at high specific heat voltages of the occupied volume.

Literature

1. Dzyubenko B.V. and other Shell and tube heat exchanger. SU. A.S. No. 937954. F28D 7/00. Priority - 11.12.80. Publ. Bulletin of inventions No. 23. 06.23.1982 - analogue.

2. Tsinkalov G.P. et al. Single-line tubular coil. SU. Patent No. 1386637. C10G 9/20. Priority - 01/07/86. Publ. Bulletin of inventions No. 13. 04/07/1988 - a prototype.

Claims (1)

A heat exchanger consisting of a bundle of heat-exchange coil pipes, the ends of which are fixed in tube boards arranged in the form of a screen, characterized in that the straight sections of several coil pipes are arranged in series in the same plane, and the bent sections are laid out in the same direction from the plane of the straight sections, and wiring bends of opposite ends, straight sections, made in different directions.

Images