SU1353979A1 - Recuperator - Google Patents

Abstract

Invention m. used in fuel combustion installations. The purpose of the invention is to increase efficiency by leveling the heat load on individual heat exchange elements. For this, Field's pipes (TF) are installed across the duct 1 and have a different length. The maximum gap between the bottom 5 of the casing 4 and the injected nozzles 2 does not exceed the diameter of the latter. By performing a TF of length, decreasing it from the center of the beam to its periphery, and the presence of a gap between the bottom 5 and the nozzles 2, the flow of air through the TF is redistributed in direct dependence on the heat transfer surface of the TF. This ensures the same thermal load on all TFs and predetermines the same temperature of air heating in all TFs. 2 Il. sl co O1 00 X) co

Description

This invention relates to heat. exchange technology and can be used in fuel combustion plants.

The purpose of the invention is to increase efficiency by leveling the heat load on individual heat exchange elements.

FIG. 1 shows a recuperator, when the gaps between the ends of the internal nozzles and the bottom of the casing are made variable due to the different length of the protruding parts of the nozzles, general view; in fig. 2 - the same, when the gaps are made variables due to the curved bottom profile.

The recuperator contains a bundle of heat-exchange elements installed in a cylindrical gas duct in the form of Field tubes of different lengths, the internal nozzles 2 of which are fixed in the outer tube plate 3, covered by the casing 4 with the bottom 5 placed relative to the ends 6 of the internal nozzles 2 with a variable clearance h, - decreasing from the center of the beam to the periphery. In one embodiment, the gap h ,, is made variable with a flat bottom 5 due to the different lengths of 4 parts 7 of the pipes 2 projecting into the casing, and the second due to the curved profile of the bottom 5 at a constant length of 4 parts of the pipes 7 of the pipes 2 outside. internal nozzles 2 are placed external nozzles 8, which form with the first Field's pipes and fixed in the internal tube plate 9. The cavity between the latter and the tube plate 3 forms the chamber 10 supplying the heated medium, and the cavity between the tube plate 2 and the casing 4 - chamber 11 exhaust heat the second medium. Field tubes are installed across the flue 1 and are made in a length that decreases from the center of the beam to the periphery. The maximum gap size h, between the bottom 5 of the casing 4 and the ends of 6 nozzles 2 does not exceed the diameter of the latter, and the ratio of the size of the gap h to the diameter d of the inner nozzle 2 is determined by the empirically derived relationship

8.17ex (1 + c;

1-CH1

(b, - / R)

.),

where 1.1, | d .; - aerodynamic drag coefficients of the central and i-th Field pipes, respectively; B, is the distance between the longitudinal axes of the central and i-th Field tubes;

R is the radius of the flue. The recuperator operates as follows.

Heating gases, the passage through the flue 1, wash outside the external pipes of 8 pipes

5 0 5 About 5

0

five

Field heating, they are heated and removed from the duct. The heated nozzles 8 radiate heat to the internal nozzles 2 and also heat them. The heated medium (air) from chamber 10 enters the gap between nozzles 2 and 8 and is partially heated by contact with their surfaces. Then the air from the gap enters the cavity of the nozzle 2, the passage through it finally heats up and enters the chamber 11 of the outlet of the heated medium to the consumer.

By making the Field tubes long, decreasing from the center of the beam to its periphery, and at the same time providing a gap between the ends of the 6 nozzles 2 and the bottom 5 of the casing 4, the flow of air through the Field tubes is redistributed, and the maximum flow is created through the central pipe The field has a maximum heat transfer surface, and the minimum flow through the end of the field is a field with a minimum surface as a whole. This ensures the same thermal load on all Field tubes and predetermines the same air heating temperature across all Field tubes, which increases the efficiency of the heat exchanger.

Claims (1)

Invention Formula A recuperator containing a beam of heat transfer elements in the form of Field tubes of different lengths installed in a cylindrical gas duct, the internal nozzles of which are fixed in an external tube plate enclosed by a casing with a bottom positioned relative to the ends of the internal nozzles with a variable gap decreasing from the center of the beam to the periphery characterized in that, in order to increase efficiency by equalizing the heat load, Field tubes are installed across the duct and are made with a length decreasing from the center of the beam to its length iferii, wherein the maximum value of the gap between the housing bottom and the inner diameter of the nozzles is not the last prevyschaet d, respectively and otnoschenie gap size to the inner diameter of the nozzle defined by the relationship , 17ep (, -l-Cbc / R;) aerodynamic drag coefficients of the central and i-th Field pipes, respectively; the distance between the longitudinal axes of the central and i-th Field tubes; radius of the flue. -tr Vtiz.t a