SU1740945A1 - Heat exchanger - Google Patents

Abstract

The invention relates to heat exchanging equipment and can be used in the chemical, petrochemical, gas industry and heat power engineering, in particular for compressor installations. The purpose of the invention is to reduce material consumption and intensify heat exchange by organizing the rotational movement of working media. The heat exchanger includes a housing 1, a heat exchange element 2 formed by Field tubes, inner 6 and outer 5 pipes of which are fixed respectively in peripheral and intermediate (PTD). The invention relates to heat exchanging equipment and can be used in chemical, petrochemical, gas industry and power engineering in particular, for compressor installations. Widely known tubular heat exchangers are known in which a cooled process product, such as compressed gas, is passed inside a sealed enclosure in the annular space, and tube plates placed parallel to each other to form a cavity (P) 8 between them 7 adjacent to the peripheral tube plate. In KK 7 and P 8, partitions are placed perpendicular to both tube plates and separating KK 7 and P 8 into the same number of compartments, with the partitions in KK 7 mixed with the partitions in P 8, and in the peripheral plate there are holes for the flow of the tube medium from compartments KK 7 in compartments P 8. Partitions can be located radially and at equal angles to each other, and their number can be equal to the number of Field tubes. If there is one partition in KK 7 and P 8 in the latter, it is installed with the cavity divided into two identical compartments, in the first - in the plane parallel to the plane of the first partition. The heat exchanger design provides for its operation countercurrent movement of working media, which intensifies heat exchange, reducing material consumption 4 hp f-ly, 5 ill. The cooling medium moves inside the heat exchange tubes. The type of such heat exchangers can also be attributed to gas coolers with longitudinally-sized heat exchange tubes. In such apparatuses, each heat exchanging tube with longitudinal fins is usually enclosed in a tubular guide casing, and then one such assembly or bundle of such elements is placed in a common sealed enclosure VI -N O SJ

Description

In the domestic structures, the heat-exchange tubes are made in the form of hot-rolled billets of the TRU cipher according to TU 1-2-452-83 of aluminum alloy AMG-2.

Heat transfer in apparatus with long-ribbed heat exchange tubes takes place between the medium being cooled, passing along the finned outer surface of the TRF tubes, and the cooling tube medium washing the smooth inner surface of these tubes. At the same time, the flow of the pipe medium moves in the annular gap between the inner wall of the heat exchanging pipe and the outer wall of the propellant pipe placed in the cavity of the TRF pipes. The displacement pipe also serves the purpose of supplying the cooling pipe medium from the outside to the active silver section of the heat exchange pipe and discharging this medium. For optimal heat exchange, a counterflow pattern of the mutual movement of the cooling and cooled fluids is necessary. However, the design of the known apparatus does not always provide a countercurrent of heat transfer fluids for the entire heat exchange surface. The design of the heat exchange tube with the displacement tube is called the Field tube. So in a similar device through Fried's tube, the flow pattern of the interaction of coolants is counter-current in principle only due to the constructively complex two-way movement of the cooled medium (gas).

In the case of a one-way gas flow, the proposed design of the pipes, housings and collectors for supplying and discharging the cooling pipe medium necessarily leads to a mixed counter-current-flow cooling system.

In various shell-and-tube heat exchangers, it is known to use structural elements called distribution devices, collector chambers, distribution manifolds or water chambers. They serve for the supply and removal of the cooling tube medium to the tube bundles of the apparatus and, depending on the design, they define the patterns of motion of the coolants in the apparatus.

In the prototype, the heat exchange tubes operate exclusively in a one-way mode of movement of coolants.

The tubular medium in the heat exchanger in question is fed in parallel to all the heat exchanger tubes at once, which in some cases causes a low velocity of the tubular medium and, consequently, a low heat transfer coefficient.

The aim of the invention is to increase the efficiency of heat exchange by organizing a counter-current movement of the cooled medium and the cooling tube medium and the reduction of the material intensity of the heat exchanger.

Figure 1 shows a longitudinal section of a heat exchanger; Fig. 2 shows sections along the elements of the apparatus: the collector chamber and the cavity between the tube plates; FIG. 3 is the same, elements with countercurrent pair-parallel flow of cooling fluid; Figures 4 and 5 are diagrams of the movement of the cooling fluid in the Field tubes.

The heat exchanger consists of a housing 1 and a heat exchange element 2, including the bottom 3 of the collector chambers, intermediate tube plate 4, heat exchange tubes

0 5 and displacement pipes 6.

In accordance with two variants of the coolant flow patterns, the end part of the heat exchanging element on the coolant inlet side consists of collector chambers and cavities 7, 8 (FIG. 1) or 9, 10 (see FIG. 3). Collector chambers and cavities are separated by peripheral tube plates 11 or 12 with round 13 or oblong 14

0 bypass holes, as well as each equipped with four 15, 16, 17, 18 or two 19, 20 longitudinal partitions. These partitions form in the collector chamber and the cavity compartments 21-28 or 29-32.

5There are nozzles of input 33 and input 34.

gas, as well as nozzles input 35 and input 36, 37 coolant.

The flow of coolants during operation of the gas cooler occurs as follows.

Cooled product - gas enters the body of the apparatus 1 through the nozzle 33, passes along the outer surface of the heat exchange tubes in the intercostal space

5 and exits through nozzle 34, making the general direction of movement relative to the heat exchange element from right to left, as shown in the sketches. Coolant enters the collector chamber

0 heat exchange element through the nozzle 35. Next, the movement of fluid, depending on the considered scheme, is as follows.

Option (see Fig.2 and 4).

5 The flow of cooling medium is directed through the nozzle 35 into the compartment 25 of the cavity of chamber 8, the mine of the compartment of the collector chamber 7. Moving through the pressure pipe, the flow enters the annular channel formed between the heat exchange pipe 5 and the pressure pipe. Here there is a process of heat exchange between the cooled gas flowing outside the pipe and the coolant flowing in the opposite direction. When the annular gap reaches the open edge of the pressure pipe, the liquid is poured into the internal cavity of the pressure pipe, and is directed away from the open end fixed to the thread in the peripheral tube plate 11 of the pressure pipe. The liquid then moves through the bypass hole 13, which connects the compartment 21 with the cavity compartment 26, due to the displacement of the longitudinal partition 15 in the collector chamber relative to the corresponding partition 17 in the cavity at an angle that allows the hole 13 to be positioned.

Subsequently, the cooling fluid passes through an annular gap in the next heat exchange pipe, enters the compartment of the collector chamber 22 and through the bypass port 13 in the compartment 27 of the cavity 8.

Further, similarly - through the annular gap in the compartment 23 and the compartment 28.

At the same time, the countercurrent of coolants is maintained. After the last heat exchanger pipe, the flow enters through the displacement pipe into the compartment 24 of the collecting chamber and is discharged from the apparatus through fitting 36.

Option 2 (see fig.Z and 5).

Accordingly, with the collector chamber and the cavity there is only one partition 19 and 20, which divide them into two compartments. This allows countercurrent pairwise (i.e. a group of two tubes) parallel coolant circuit. Through the nozzle 35, the liquid enters the lower compartment 31 of the cavity 10. It moves further along the annular channels of the two lower heat exchanging tubes and through the displacement pipes settles into the compartment 20 of the collecting chamber. Then, through the oblong bypass hole 14. made in the peripheral tube plate 12, due to the upward displacement of the partition 19 relative to the partition 20 of the cavity 10, the flow enters the compartment 32 in the upper part of the cavity and repeats the movement opposite to the gas flow in the annular channels of the upper pair of heat exchangers pipes. At the end of this stroke, the tubular medium enters the upper compartment 30 of the collector chamber 9 and then leaves the apparatus through the nozzle 37.

The new design of the cover-collector allows to reduce the total material consumption of the new device by 10-15%, and the specific consumption, respectively

20-30%. The countercurrent flow pattern of coolants allows, other things being equal, to increase the cooling depth of the cooled product by about 2.5 °.

Claims (5)

1. A heat exchanger comprising a casing with a Field's tube bundle, the inner and outer tubes of which are fixed respectively in the peripheral and intermediate tube plates placed parallel to each other to form a cavity between them, and a collector chamber for the tube medium adjacent to the peripheral tube plate, characterized in that In order to reduce material consumption and intensify heat exchange by organizing counter-current movement of working media, it is equipped with partitions installed in the collector chamber and in the cavity, perpendicular to the tube plates and separating the chamber and the cavity by the same number of compartments, the partitions in the chamber being offset relative to the partitions in the cavity between the tube plates, in the peripheral of which there are holes for the flow of the tube medium from the compartments of the collector chamber into the compartments of the cavity, and the number of these holes tiy one less than the number of compartments in the chamber. 2. The heat exchanger according to claim 1, about t l and h and y and with the fact that the partitions are installed radially. 3. Heat exchanger according to claim 2, characterized in that the partitions in the collector chamber and in the cavity between the tube plates are located at equal angles to each other. 4. The heat exchanger according to claims 2, 3, about tl and h and y and with the fact that the number of partitions and the collector chamber and in the cavity between the tube plates is equal to the number of Field's tubes. 5. A heat exchanger according to claim 1, in accordance with claim 1, so that, in order to intensify heat exchange in the presence of one partition in the collector chamber and in the cavity between the tube plates, in the last partition installed with its division into two identical compartments, and in the collector camera - in a plane parallel to the plane of the first partition. 1C 6 i and  in 3 - Buff a B-6 / 7/5 23 24 35 21 & LJ /// J 17 YY 27 t -v / x. fig j fj five fig J i N