The heat exchanger
(57) Abstract:The invention is intended for use for gasification cryogenic fuel in aircraft gas turbine engines. The heat exchanger contains are parallel to one another tube connected with the inlet and outlet manifolds and placed in the shell, which forms a cavity with inlet and outlet for flow of the heat carrier, and according to the invention the heat exchanger is mainly used for the gasification of cryogenic fluid flowing within the tubes, and the tubes are located one after the other with a step S and have an outside diameter of dnin addition, tubes are installed in groups step between groups S1determined from the ratio of 1.5 S1/dna 2.5 with a step S, determined from the ratio of 1.5>S/dn1,1. The invention improves the efficiency of the heat exchanger, reduces the external resistance and keeps it from freezing from the coolant. 1 C.p. f-crystals, 3 ill. The invention relates to the field of heat exchangers and is intended primarily for gasification cryogenic fuel in aircraft gas turbine engines (AHTD). In AGTD working on cryogenic fuel required is CLASS="ptx2">A known heat exchanger - gasifier fuel AHTD installed at the entrance of the compressor (GB N 1022952, CL F 4 S, publ. 1966). The disadvantage of this heat exchanger is its low reliability due to possible freezing of the tubes of the heat exchanger. The engine of this heat exchanger is almost unusable at low flight speeds, when the air temperature at the inlet is close to the ambient temperature. The heat exchanger in this case is inefficient because of its freezing.The location of the heat exchanger at the inlet to the compressor also reduces the reliability of the engine due to the probability of seal failure in flight. In this case, the path AHTD formed an explosive fuel-air mixture, such as "explosive gas" hydrogen fuel.This disadvantage is eliminated in the heat exchanger in the form of a tubular coil that is installed in the exhaust stream (US N 1799249, CL 165-60, publ. 1974 ). The disadvantage of this heat exchanger is freezing the surface of the tube-side fluid, containing water vapor, due to the high heat transfer from the cryogenic environment and its low temperature.From theory of heat transfer is known that the higher the ratio talek possible formation of a solid phase (ice, frost) due to condensation and freezing of water vapor contained in the coolant.Large speed cryogenic environment in the series connected coils of the coil induce a higher heat transfer coefficient and, consequently, the formation of ice.These disadvantages of these heat exchangers is fixed in the heat exchanger containing spaced parallel to one another tube connected with the inlet and outlet manifolds and placed in the shell, which forms a cavity with inlet and outlet for flow of the heat carrier (SU 434251 A, F 28 D 7/16, 30.10.1974).The disadvantage of this heat transfer is increased hydraulic losses in the flow of coolant flow over the heat exchanger from the outside. The above solution is the closest analogue of the invention.It is known that losses in the external flow, flowing consistently located tube, increase with increasing spacing between the tubes S to a value of more than 1.5 of its diameter dH, i.e., the ratio S/dHmust be < 1,5 (see I. E. Idelchik. Handbook of hydraulic resistance. M: mechanical engineering, 1975, page 397, and A. M. Krapivin and other Hydraulic resistance of a homogeneous tubes of the Oia and resistance, as a consequence, increase efficiency, if the heat exchanger is located in the path of AHTD, it is necessary to perform heat exchangers with a compact arrangement of tubes, with S/dH1,5.However, when a large number of tubes in a bundle over along the beam becomes similar to the flow along a rough plate and on the surface of the beam is formed thick cooled layer of fluid, which due to its thermal resistance reduces the efficiency of heat exchange between the coolant and the cryogenic fluid. In "Calculation and experimental investigation of hydraulic and heat transfer in tube bundles, streamlined unlimited flow" (of Those. the report CIAM N 30208/3, 1989) shows that reducing the number of tubes in a bundle from 11 to 6 of the Nusselt number (Nu), describing the heat transfer from the outer side of the beam increases by approximately 2 times. The probability of freezing shesticlennogo beam is virtually eliminated due to its very high efficiency.The problem to which the invention is directed, is to create a highly efficient heat exchanger on all modes, with a small external resistance and lack of freezing tubes from Talana task is solved by the heat exchanger contains are parallel to one another tube connected input and output manifolds and placed in the shell, which forms a cavity with inlet and outlet for flow of the heat carrier, and according to the invention the heat exchanger is mainly used for the gasification of cryogenic fluid flowing within the tubes, and the tubes are located one after the other with a step S and have an outside diameter of dHin addition, tubes are installed in groups step between groups S1determined from the ratio of 1.5 S1/dH2,5.In addition, the tubes in groups installed in increments of S, determined from the ratio of 1.5 > S/dH1,1.The calculations are confirmed by experimental data showed that the heat transfer (criterion Nu) 20 of the tube bundle, consisting of four groups of five tubes in each group with a relative spacing between groups S1/dH= 2,33 and the relative spacing between tubes in the groups S/dH= 1,17, 2 times more heat 20 of the tube bundle, made in the usual way with a step between the pipes S/dH= 1,17.The present invention is represented by the drawings, where
in Fig. 1 shows a General view of the heat exchange is piping set and step between them.The heat exchanger consists of a shell 1 with an internal cavity 2 for flow of fluid from the inlet 3 and outlet 4. In the cavity 2 is the inlet manifold 5 with a cavity 6 to enter the cryogenic fluid and an outlet manifold 7 with a cavity 8 for the outlet of the cryogenic fluid. The inlet 5 and outlet 7 collectors connected in parallel spaced rows of tubes 9 with an outer diameter of dHlocated one after the other in increments of S. Tubes 9 are arranged in separate groups in increments of S1between the groups.The inlet manifold 5 is provided with a nozzle 10 for supplying a cryogenic liquid 11 and the outlet manifold 7 is supplied by a pipe 12 to exit the heated cryogenic fluid 13. The input 3 of the cavity 2 is designed to supply hot fluid 14 (for example, products of combustion after the turbine GTE), and the output of the 4 - for chilled coolant 15.In Fig. 3 shows that the heat transfer (criterion Nu) increases with decreasing number of tubes nTrin the beam, reaching a maximum value at nTr= 3. For example, if , when nTr= 10 Nu = 300, and nTr= 5 Nu = 500, i.e., heat dissipation is increased in 1.7 times.The heat exchanger works as follows.Cryogenic fuel 11 in the liquid sustaina with the coolant 14 gasified, and in the gaseous state is supplied into the cavity 8 of the output manifold 7 through the pipe 12 in the direction of arrow 13 is sent to the consumer, for example the combustion chamber. On the last tube of each group breaks formed the boundary layer of the coolant, resulting in the efficiency of the heat exchanger increases, prevents its freezing from the outside and reduces the hydraulic resistance. 1. A heat exchanger containing spaced parallel to one another tube connected with the inlet and outlet manifolds and placed in the shell, which forms a cavity with inlet and outlet for flow of fluid, wherein the heat exchanger is mainly used for the gasification of cryogenic fluid flowing within the tubes, and the tubes are located one after the other with a step S and have an outside diameter of dnin addition, tubes are installed in groups step between groups S1determined from the ratio of 1.5 S1/dn2,5.2. The heat exchanger under item 1, characterized in that the tubes in groups installed in increments of S, determined from the ratio of 1.5>S/dn1,1.
FIELD: power engineering.
SUBSTANCE: heat exchanger comprises pipes with spiral-ring fins. The fins are provided with longitudinal slots. The pipes in the heat exchanger are arranged vertically.
EFFECT: enhanced efficiency.
FIELD: heat exchange.
SUBSTANCE: heat exchanger comprises housing with front and back supporting lags of different height, lens compensator, pipe bundle with branch pipes for supplying and discharging heat-transfer agent, and front water chamber with the baffle which divides the pipe bundle into two sections. One of the sections is provided with branch pipes for supplying and discharging fluid to be heated, and the other section defines the back water chamber. The lens compensator is mounted in the vicinity of the back water chamber, and back supporting lag of the housing is provided with the additional supporting unit and mounted on the housing upstream or downstream of the lens compensator.
EFFECT: improved heat exchange and enhanced reliability.
FIELD: heat exchange apparatus.
SUBSTANCE: surface heat exchanger comprises casing provided with bearing lags, lens compensator, pipe bench with branch pipes for supplying and discharging heat-transfer agent, and front water chamber with the baffle that divides it into two sections. One of the sections is provided with the branch pipes for supplying and discharging of the fluid to be heated, and the other section defines the back water chamber. The pipe bench inside the housing is separated by the horizontal baffle provided with the by-pass port interposed between the lens compensator and back water chamber. The top and bottom sections of the pipe bench are separated with the vertical baffles arranged symmetrically to each other.
EFFECT: improved heat exchange and enhanced heat power and reliability.
FIELD: heat transfer equipment, particularly used in furnaces characterized by descending combustion product movement, namely in power installations such as exhaust gas heat utilizing devices.
SUBSTANCE: heat-exchanger comprises heat-exchanging pipe bundle provided with hexahedral connection parts formed at pipe ends and defining tube and annular spaces. The heat-exchanger has annular shape in top view and has inner window adapted to convey solid particles, namely combustion products. Connection parts of the pipes are welded with each other. Annular spaces defined around the pipes are closed with separate plates made as elongated hexahedrons tangentially adjoining paired pipes and welded with each other. One heat-exchanging pipe is removed from both heat-exchanger sides relatively vertical axis thereof. Inlet and outlet connection pipes communicated with annular space for heat transfer agent receiving are welded to free hexahedral cells formed after heat-exchanging pipes removal. Cells from opposite sides of connection pipes are closed with caps.
EFFECT: increased heat-exchanger strength and heat-transfer efficiency, elimination of complicated structural units, possibility to adapt heat-exchanger for burners characterized by descending combustion product movement.
FIELD: heat-exchangers, particularly submersible ones.
SUBSTANCE: heat-exchanger comprises body perforated with orifices located at cylindrical inlet chamber height, tube plate, tube bundle arranged so that coolant is directed transversely to the tube bundle. Heat exchanger also has displacers and spacing grid. Hexahedral collector is formed on tube bundle at inlet chamber height so that the collector is coaxial to the body. The hexahedral collector perimeter is free of tubes. Radial channels extend from collector corners to tube bindle perimeter. The radial channels are also free from tubes. Displacers are installed in spacing grid below inlet chamber.
EFFECT: possibility of uniform coolant flow over each heat-exchanging tube, provision of equal temperature characteristics at each tube outlet and reduced vibration of tubes in tube bundle.
FIELD: heat exchange equipment, namely used in oil processing, chemical, gas, oil and power production industry branches.
SUBSTANCE: heat exchanger includes shell having bundle of heat exchanging tubes, inlet and outlet branch pipes for draining fluid from space between tubes, collector chamber connected with one end of shell and having branch pipes for inlet and outlet of tube fluid, collector tube wall and lengthwise heat insulated partitions mounted along axis of collector chamber and axis of shell. Lengthwise partition of shell is provided with sealing members in the form of packs of longitudinal bands arranged between partition and inner surface of shell symmetrically relative to lengthwise partition. In places where cross ends of sealing longitudinal bands adjoin to tube wall that is in trihedral angles, sealing units in the form of packs of bands or petal- or lug-shaped plates are mounted symmetrically relative to lengthwise heat insulated partition. Said packs are closely secured to tube wall; each band or plate is arranged in such a way that it adjoins to longitudinal bands and has camber to side of sealing longitudinal bands.
EFFECT: possibility for providing labyrinth seal of trihedral angle between inner surface of shell, sealing longitudinal bands and tube wall.
4 cl, 16 dwg
FIELD: heat power engineering.
SUBSTANCE: multi-sectional heat exchanger comprises sections made of at least two rectilinear pipes whose ends are provided with collectors which are interconnected in series through a tube bend. Each section is made of a set of pipes with piping collectors. The sections are parallel one to the other. The area of the cross-section of the bend tube is no less than that of the collector pipes.
EFFECT: reduced hydraulic drag and enhanced efficiency of heat exchanger.
SUBSTANCE: invention can be used for heating liquid and gas in technological processes of oil refining, petrochemical, gas and other industries. Heat exchanger contains a casing, pipe walls and grates with heat exchange pipes. Between transverse walls damping baffles that contain rectangular disk packages mounted between rows of pipes parallel to each other in a transverse plane exchanger, and rectangular disk packages of rectangular cross section mounted between rows of pipes parallel to each other in another heat exchanger transverse plane are installed.
EFFECT: increase of endurance.
3 cl, 7 dwg
SUBSTANCE: vortex apparatus comprises casing wit upper and lower covers, the lower one making a condensate collector, gas inlet/outlet and condensate outlet branch pipes, partitions, vortex pipe, initial compressed gas flow rate control device and condensate-separation units. Aforesaid vortex pipe includes a cold flow and hot flow pipes. Initial compressed gas flow rate control device incorporates a screw-type tightening device (STD) with adjusting washer furnished with a cross-piece with stem arranged in the STD membrane hole. The said stem passes via the cold flow pipe and through the gland in the upper cover out from the apparatus and is furnished with the rotation drive. The condensate-separation units comprise pipe laid between the said partitions, two pairs of crosswise slots arranged opposite to each other on the hot flow pipe at the distance of (1.25 to 1.45) d, where d is the pipe ID, from the STD edge and shifted relative to each other by 90°. Note that the said slots are arranged along the axis at the distance of (0.15 to 0.25) d. The circular chamber outlet channels, inside the hot flow pipe, are terminates at the gap between the casing wall and thin-wall cylinder. The hot flow pipe outlet is furnished with a nozzle and thin-wall cylinder is provided with confuser-diffuser element making an injector.
EFFECT: control over initial compressed gas flow rate by external effects and higher efficiency of condensation-separation processes.
1 cl, 4 dwg
SUBSTANCE: invention is of relevance for operation of apparatus for air cooling of gas and is to be utilised in power engineering industry. The proposed method of the heat exchanger apparatus fabrication envisages the following activities: fabrication of finned heat exchange tubes, a framework, at least a single apparatus section with lateral walls and beams joining them together, gas inlet and outlet chambers; packing the section with a bundle of finned one-way-flow heat exchange tubes; fabrication of a manifold for gas supply and removal, a support structure and their assembly. The section walls are represented by channel bars with shelves turned towards the tubes and are equipped with fairing displacers forming the U-bar reinforcement ribs. One of the methods of the apparatus heat exchanger section fabrication envisages positioning an optimal number of tubes within the section in accordance with the dependence specified within the framework of the invention concept. An alternative method envisages assembly of the section elements on a holding frame designed within the framework of the invention concept. A third method envisages assembly of the elements in a specific sequence combined with performance of hydraulic pressure testing. The method of fabrication of the apparatus chamber for gas inlet or outlet envisages manufacture of the chamber elements and their assembly in a sequence developed within the framework of the invention concept. The method of fabrication of the gas delivery and removal manifold envisages manufacture of the manifold body sections and their assembly with the help of the tool tab designed within the framework of the invention concept. Method of hydraulic pressure testing of the apparatus sections envisages mounting the section to be tested on the hydraulic test bench designed within the framework of the invention concept with the pressure increase and drop modes as per the dependence given. Method of the manifold hydraulic pressure testing envisages it being mounted on the hydraulic test bench or a loft with the help of support structures designed within the framework of the invention concept.
EFFECT: enhanced effectiveness and precision of assembly of the apparatus and elements thereof combined with reduction of labour and material consumption, reduction of hydraulic losses occurring in the apparatus as well as technological simplification of the hydraulic pressure testing of heat exchanger sections and manifolds of the apparatus for air cooling of gas, improved effectiveness and reduced labour intensity of their performance.
25 cl, 30 dwg