SU1010405A1 - Tubular recuperator - Google Patents

Abstract

1. A TUBULAR RECOVERER containing a bundle of i-shaped heat exchange tubes installed in the duct, forming longitudinal and transverse rows and having identical perimeters in cross section, the peripheral tubes of longitudinal rows being made with a circular cross section, characterized by the fact that in order to increase reliability, pipes in the longitudinal row in the direction from the periphery of the latter to the center, with decreasing flow area. 2. The recuperator according to claim 1, that is, that all the pipes, except for the peripheral ones, are made in cross-section in (A form of axisymmetric ovals. Eojffyjc 4i O P1 F9tf

Description

The invention relates to metallurgy, in particular to equipment for heating air, and can be used in the chemical industry and energy.

Known tubular recuperators containing beams of I-shaped heat exchange tubes installed in the gas duct. ,

In such recuperators, it is proposed that the less heat-stressed heat exchanger tubes fll be phased. The disadvantage of this design is that a significant part of the kinetic energy of the flow is lost in the diaphragms, the coolant flow through these elements is reduced, and the heat transfer from the heat transfer pipe is reduced, which worsens heat transfer to the heat source. .

The closest to the invention to the technical essence is a tubular heat exchanger containing a bundle of U-shaped heat exchange tubes installed in the duct, forming longitudinal and transverse rows and having the same perimeters in cross section C 2 3 The disadvantage of the known heat exchanger is the uneven flow rate of the cold heat carrier ; by individual items.

Through the first row of heat exchange elements, in the course of the movement of the hot coolant, the minimum consumption of cold coolant passes because of its maximum length. At the same time, the temperature of the hot coolant in front of the first row of elements of heat14a is high, and the effect of the heat in the heating system is the largest.

All of these factors1 1 increase the temperature of the nepBotd p wall elements, which leads to their fast burnout and the failure of the entire heat exchanger.

The aim of the invention is to increase reliability.

The goal is achieved by the fact that in a tubular heat exchanger containing a bundle of i-shaped heat exchange tubes installed in the gas duct, forming longitudinal and transverse rows and having the same perimeters in cross section, the peripheral tubes of longitudinal rows are made with a circular cross section, A keickdom of the longitudinal row in the direction from the periphery of the latter to the center is made with a decreasing flow section.

In addition, all pipes except the peripheral ones can be made in cross-section in the form of axisymmetric ovals.

FIG. 1 shows a tubular heat exchanger; a vertical section in FIG. 2 - section A-A in FIG. one.

The tubular heat exchanger contains a bundle of U-shaped heat exchange tubes 2 installed in the duct 1, forming longitudinal and transverse rows and having identical perimeters in cross section. The pipes 2 in each longitudinal row in the direction from the periphery of the latter to the center are made with a decreasing flow section.

All pipes 2, except for the peripheral, can be made in cross sections in the form of axisymmetric ovals.

The pipes 2 are fixed on the tube plate 3 and connected to the inlet manifold 4 and the outlet - 5.

Truokuchaty recuperator works as follows.

The cold coolant from the inlet manifold 4 enters the heat-exchange tubes 2, where it is heated by the heat of the hot coolant in the gas duct 1, and then through the manifold 5 is sent to process needs.

The cross-sectional area of heat-exchange tubes may be reduced by an amount determined by the formula, which is derived on the basis of equal air flow rates in the first and I -th heat-exchange tubes.

R

D €, .N-1

d where

the difference between the flow sections of the first and the i-th pipe in one longitudinal row;

the flow area of the first pipe; SiOTi summarizes the resistance coefficients of the 1st and 1st elements, which are determined from literature data.

The implementation of heat exchange pipes with a decrease in their flow area 5 from the periphery to the center allows

increase the speed of the coolant, which intensifies the heat exchange and protects the peripheral pipes from burning.

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Claims (2)

(54) 1. TUBULAR RECOVERATOR containing a bundle of gas ducts: 1> -shaped heat-exchange tubes forming longitudinal and transverse rows and having the same perimeters in cross section, the peripheral pipes of longitudinal rows being made with a circular cross section, characterized in that that, in order to increase reliability, the pipes in each longitudinal row in the direction from the periphery of the latter to the center are made with a decreasing flow cross section ” 2. Recuperator according to π. 1, characterized in that all the pipes, except the peripheral ones, are made in cross section in the form of axisymmetric ovals.