UA9612U - Plate heat exchanger - Google Patents

Abstract

A plate heat exchanger has a bearing structure û frame on which one places a pack of crimped plates. Each of the plates has inlet and outlet collector openings in the angle parts of the plate. The plates form in the heat exchanger two systems of channels. The surface of heat exchange inside the channels is restricted by the walls of the plates and the nodes of channel tightening in contour of the plates, and a pair of idle corner apertures.

Description

Description of the invention

The utility model refers to plate heat exchangers developed and manufactured in 2 mechanical engineering, and used for the process of transferring thermal energy from a hot coolant to a cold one in industrial technologies, in hot water preparation and heating systems of buildings, in food, chemical and other fields of technology.

Known plate heat exchangers for the transfer of thermal energy, designed for a user-specified heat load, have the required heat exchange surface area in the form of a package consisting of 70 of a certain number of plates. The plates are connected in two systems of hermetic channels and are clamped between the movable and fixed plates on the frame of the heat exchanger. Thermal energy from the hot coolant to the cold one is transferred through the wall of the plates, which is made in the form of a corrugated heat exchange surface. The size of the total area of the plates or their number in the heat exchanger determines its cost |11).

The task of reducing the cost of a plate heat exchanger can be solved by improving its technical 72 Characteristics, which is associated with the improvement of heat transfer plates and increasing the reliability of channel sealing units. The technical characteristics of the heat exchanger are improved by increasing the heat transfer coefficient, reducing the energy consumption for pumping heat carriers through the heat exchanger, as well as increasing the efficiency of the thermal process and the reliability of the heat exchanger. At the same time, the number of plates in the heat exchanger can be reduced.

A plate heat exchanger is known, in which corrugated plates are installed on the frame, having an average rectangular zone of heat exchange, and two triangular zones for the distribution of coolants along the width of the channel (see US patent

Mo. 4 781 2481 (21.

In the triangular zones between the protrusions and depressions of the corrugations, there are channels for the heat carrier connecting the corner holes of the plate with the corner zone of heat exchange. These channels are adapted to mix the flow 29 of the coolant by passing across the corrugations. The heat exchanger, the description of which is given, has a number of disadvantages. First, in the triangular zones of the surface of the plate, a disordered mixing of the flow is formed, which increases the pressure loss compared to the rectangular zone; a "pure" vortex gives greater heat transfer than chaotic mixing in a triangular zone. Between the triangular and rectangular zones, there are transition zones, which are located across the plate, which creates additional local hydraulic resistance to the flow of the coolant and increases the energy intensity of the thermal process. Second, the corrugations of the triangular zones of the plate do not smoothly connect with the corrugations of the rectangular zone, "-- which also creates additional local hydraulic resistance and energy losses. Thirdly, all the corrugations of the rectangular zone have the same length, which creates an uneven field of heat carrier velocities across the plate, and the rubber gasket is in a closed groove, which can lead to its crushing when the package Ф of plates is tightened. The durability of the sealing unit is quite short. 325 A plate heat exchanger is known for heat exchange between two fluids in the presence of two fluid flows, one of which is significantly larger than the other | see patent of the Russian Federation 19 KY (11) 2110030 (131)) IZ). This plate heat exchanger is of a well-known design (1), which contains several rectangular corrugated plates, each of which has holes of different diameters in the corner zones and a rectangular heat exchange zone. Disadvantages: in the triangular zones, the corrugations are curvilinear and do not connect smoothly, without local hydraulic resistances, to the corrugations of the rectangular zone. There are transition zones across the entire plate. Local hydraulic resistances in the interplate channels increase the energy efficiency of the heat process and worsen the thermohydrodynamic performance of the heat exchanger.

From" It is known a plate heat exchanger with fastening of seals on the periphery of the plates, see US patent Mo 5 727 6201 4). The periphery of the plate is formed by many recesses that are located perpendicular to the groove in the places where the gasket elements are attached. Designation of transverse grooves for the gasket - recesses - glueless fastening of the gasket with an element of this gasket. The plate has holes in the corner zones for the entrance and exit of the coolant. The corrugations in these zones are curvilinear and do not have a smooth connection with the corrugations of the rectangular zone

Ge") of heat exchange. The disadvantages of the plates are the same as in the analogues described above - the increased energy consumption of the thermal process for equal thermal loads compared to the useful model proposed by us. - The closest in terms of technical substance to the proposed object (prototype) is a plate heat exchanger, which has 20 heat transfer plates of two types with different forms of corrugations |5)І. According to this patent, a package of plates is assembled from two types of plates that differ in the shape of the corrugations and their height on one of the pairs of plates. At the same time, channels for coolants with different thermal and hydromechanical characteristics are obtained. On one of the types of plates, straight longitudinal corrugations (intervals) with a height greater than the main pattern of corrugations are extruded along the corrugated surface. The second type of plates does not have such longitudinal corrugations of greater height. IN

SS o5 package, which is assembled from plates of the first and second types, alternating, channels of different equivalent diameters emerge. A liquid with a high viscosity is fed into the channels of a larger equivalent diameter, and the heat exchange proceeds in a laminar flow mode with less hydraulic resistance and without turbulence of the coolant. The disadvantage of the heat exchanger according to the US patent Mo 4911 235 is a decrease in the carrying capacity and a decrease in the intensity of heat transfer and, as a result, an increase in the required number of plates and the cost of the heat exchanger. Thus, this heat exchanger is effective only when working with highly viscous contaminated heat carriers in the laminar flow regime, which is relatively rare in practice.

Disadvantages of known plate heat exchangers (1) include the non-uniform distribution of heat carrier flow rates across the width of the inter-plate channels, which causes a decrease in heat transfer in some sections of the channels. It is necessary to be able to adjust the pressure loss limits in the channels due to the designs of the plates and shapes of the turbulators (corrugations).

The technical result of the useful model is an increase in the efficiency of heat exchange, a decrease in energy consumption, a decrease in the number of plates in the heat exchanger, as well as an increase in the reliability and durability of elastic seals (gaskets) in the channels, compared to analogues and the prototype.

The useful model is aimed at improving the design of plate heat exchangers with the aim of making them cheaper, which is ensured by increasing the efficiency of heat exchange, increasing the possibilities of adjusting pressure loss limits and energy saving, as well as increasing the reliability and durability of the sealing nodes of inter-plate channels.

Technically, this is achieved by the fact that in the proposed plate heat exchanger, the channels (package of plates) /0 can be assembled from one or several different types of plates, differing from each other in the shape and size of the corrugated surface (quality of the heat exchange surface).

According to the invention, distinctive features of the heat exchanger are shown in the drawings (Fig. 1-6).

Fig. 1 shows the proposed heat exchanger schematically in axonometry.

In Fig. 2 - a plate of small hydraulic resistance (Type M).

In Fig. 3 - a plate of large hydraulic resistance (Type B).

Fig. 4 shows the triangular shape of the corrugations and the ratio of their sizes in a cross section along A-A in Fig. 3.

Fig. 5 shows the shape of the grooves for the gasket (top view).

Fig. 6 is a cross-section of a package of plates in working condition in the area of the channel sealing unit with a gasket according to the B-B section in Fig. 5.

The plate heat exchanger (Fig. 1) consists of a frame with an upper supporting rod 1, on which a package of corrugated plates 2 (type M - low hydraulic resistance) and Z (type B - high hydraulic resistance) is suspended and can move along the rod, which are fixed by the lower rod 4. Each plate in the package is rotated 1809 in the plane of the adjacent plate, with the corrugations mutually intersecting. In working condition, the package is compressed to a hermetic state between the stationary plate 5 and the movable plate 6 with screw ties 7. The plates have nozzles for the inlet and outlet of coolants 8 (hot) and 9 (cold). The frame of the heat exchanger has an end rack 10 with a support. WITH

To seal the inter-plate channels and distribute coolants along the hot and cold channels, the plates have elastic sealing gaskets 11, fixed in specially shaped grooves on the plates. The heat exchanger has two systems of sealed channels for hot (the first system) and cold (the second system) coolant, which are separated by plate walls.

The plates have a different surface shape, which gives the channels different thermo-hydrodynamic characteristics. -

Fig. 2 shows a plate with a new M-type corrugation shape, and Fig. 3 shows a plate with an O-type corrugation shape

B.

Each plate is made in the form of a corrugated surface, which creates turbulence in the flow of liquid, which ia

C5 moves in the channel, and the sealing unit is in the form of a groove of a complex shape with an elastic gasket fixed in it. The corrugations of type B plates are the same in shape and size and are located symmetrically at an angle to the longitudinal axis of symmetry of the plate. Plates of type M on one side of the longitudinal axis have the same corrugations as on the plate of type B, and on the other side of the longitudinal axis of symmetry of the plate, the corrugations are parallel to this axis (Fig. 2, position 12). not)

To increase the uniformity of the distribution of the liquid flow across the width of the plate and reduce the pressure loss in the channel, the corrugations near the lateral longitudinal edges of all plates have different lengths, for example, the corrugations after one are shortened and near the edge, as shown in Fig. 2. Corrugation 13 is shortened, and corrugation 14 is extended to the groove for the gasket. "" As shown in Fig. A4, the corrugations of the plates in their cross-section (see page 4 of the description - captions to the drawings) have the shape of an isosceles triangle, the vertices of which are rounded at the radius K. This form of corrugations, compared to other forms, creates energy savings during turbulence of the boundary layer of the liquid flowing in

Te) interplate channels.

In Fig. 4, points E and o define the rectilinear section of the corrugation, which affects the hydrodynamics of the liquid flow,

Fo and the lines E-E-C-E show the area of the channel adjacent to the rectilinear sections of the corrugation. The remaining sections - the perimeter of the transverse area of the channel are adjacent to the curvilinear sections of the corrugation. O is the center of a circle of radius K, whose arc (459-452) serves as the apex of the corrugation. o The point M fixes the distance r at which the centers O of the corrugation radii are located.

Segment A determines the step between the corrugation tops.

A distinctive feature of the proposed shape of the corrugations is that the corners of the triangular shape of the corrugations (vertices of the corrugations) are rounded with the radius of the circle K, the center of which is set back from the top of the corrugation (triangle) by the amount v- , where n - iK- 5 the height of the corrugation.

The grooves for the elastic gasket along the contour of the plate and around the collector holes, as shown in Fig. 5, have transverse outlets 15 and 16 located periodically along the length of the groove, into which a part of the gasket is squeezed out during its compression in the plate package. At the same time, the durability of the elastic gasket increases.

The width of the groove for the gasket on the plate is different (Fig. 5). In places near the collector holes, the groove has a smaller width b than along the outer contour of the plate a, i.e. a»bB. This makes it possible to improve the sealing of areas near the collector holes.

To reduce pressure losses on the inlet-outlet sections of the plates, the corrugations have a straight, sloping shape along the flow 65 (Fig. 3), which connects to the collector holes without local hydraulic resistances, 17 and 18.

Fig. b shows in the working position the sealing unit by laying channels between the plates in a cross-section along B-B in Fig. 5.

The proposed plate heat exchanger works as follows:

The cooled coolant through the fitting 8 on the fixed plate 5 is fed into the distribution collector formed by a package of compressed plates and, according to the location of the gaskets on the plates near the collector holes, enters the channels for the hot coolant located in the package through one of the channels for the cold coolant.

The heating medium is fed into its distribution manifold through another fitting 9 and distributed into channels on the other side of each plate. The heat from the flow of the cooled liquid through the wall of the plate /o is transferred to the heated liquid. The intensity of the heat transfer process, the pressure loss of the working media and the energy consumption to overcome them characterizes the main indicator of the purpose of the heat exchanger - its heat energy efficiency, which is inversely proportional to the required number of plates in the heat exchanger.

To increase the efficiency of the heat exchanger, a method of turbulating the boundary layer of the liquid near the walls of the plates and creating a uniform distribution of heat carrier velocities in the channels is used, by means of 7/5 devices of special forms (the subject of the invention) of the heat exchange surface, for example, corrugated ones. To create optimal heat exchangers for the output data specified by the consumer, a wide range of different layouts of plates of different types, determined by computer calculations, is required.

The presence of plates of types B and M and their pairs of type BM allows to make the most complete use of allowable pressure losses in the heat exchanger, which is determined by various optimization calculations. The consumer properties of the heat exchanger depend on the device of the heat transfer plates. So, for example, the location of half of the corrugated field with longitudinal corrugations along the longitudinal axis of the plate paired with the adjacent plate with inclined corrugations creates three-dimensional turbulence of the fluid flow and reduces pressure losses in the channel due to the rotational movement of the flow streams, with a partial decrease in heat transfer. The optimal layout of different types of plates in the heat exchanger is determined by calculations, the possibilities of which are expanded by the proposed useful model.

Corrugations shortened through one of the side edges of the plates (Fig. 2) increase the speed of the liquid flow in these places, improve the distribution of the flow across the width of the channel, reduce pressure losses and increase the quality of heat treatment (pasteurization) of food liquids.

The triangular shape of the corrugations in the cross section, with the corners rounded with the optimal radius (Fig. 4), increases heat transfer more than the increase in pressure losses in the channel. This form is the most technological in the village

From Production (when stamping such a letter).

The shape of the grooves on the plate for the placement of elastic spacers (Fig. 5) increases the performance and durability of the spacers, because the elastic material of the spacer is not overloaded by the specific pressure during compression. "at

Part of the gasket material goes into the side grooves, maintaining a certain specific pressure for sealing the channel and not collapsing from crushing, which does not exist in this case. Me

To increase the reliability of sealing the channel near non-working collector holes on the plates, it is suggested to reduce the width and increase the height of the gasket (Fig. 5). The need for such a device of the sealing unit in the specified places is caused by the increased mobility of the groove for the gasket in these places in the compressed package of plates. The specific pressure on the elastic gasket in these moving places of the plates increases, which will improve the sealing of these areas. Local hydraulic resistances in the interplate channels, not related to the intensification of heat transfer, worsen the thermal energy characteristics of the heat exchanger, which leads to its increase in price. The proposed set of distinctive features of our device is aimed at eliminating this shortcoming. . The task of a useful model will be solved if there are corrugations at the entrance-exit sections of the coolant in the channel. rectilinear and will smoothly connect with the passages from the collector holes of the plates and the main field of corrugations, as shown in Fig. 3, positions 17 and 18. Pressure losses will decrease in these areas of the plates.

The set of distinctive features of the heat exchanger and plates for it, proposed by the invention, increases it

Ge) heat energy efficiency. This allows you to use a smaller number of heat exchange plates than in the known plate heat exchanger when solving heat exchange tasks, or to make each plate

Me, smaller sizes. - In the latter case, it is possible to reduce the cost of not only the package of plates, but also the frame of the heat exchanger on which the plates are installed. d" To the list of drawings and the description of all positions on the drawings

Fig. 1 - Plate heat exchanger in the open position, in axonometry, with a package of two types of plates. 1. The supporting upper bar of the heat exchanger frame; 2. Type M plate;

Han Z. Type B plate; 4. The lower rod of the heat exchanger frame; 5. The plate is stationary; 6. The plate is movable; 7. Tightening screws; in 8. Pipe for entering hot coolant; 9. Pipe for entering cold coolant; 10. End rack.

Fig. 2 - Corrugated plate of type M. 11 - elastic gasket; 65 12 - corrugations parallel to the longitudinal axis of the plate; 13 - shortened corrugations;

14 - elongated corrugations with access to the groove for laying the circuit.

Fig. 3 - Type B corrugated plate 11 - elastic gasket; 13 - shortened corrugations; 14 - elongated corrugations with access to the groove for laying the circuit; 17 - straight sloping corrugations of the coolant outlet section; 18 - straight, inclined corrugations of the heat carrier inlet section.

Fig. 4 - Triangular shape of corrugations in a cross section and the ratio of their sizes. 70 Fig. 5 - The shape of the groove for the gasket. 13 - shortened corrugations; - transverse outlet for compressed gasket in places to the outer edge of the plates a - greater width of groove for gasket b - smaller width of groove for gasket 15 16 - transverse outlet for compressed gasket in places of junction of groove with long corrugations;

Fig. 6 - a cross-section of a part of a package of plates along A-A. 11 - elastic gasket; 14 - the wall of the elongated corrugation; 15 - transverse outlet for a compressed gasket near the outer edge of the plate; 16 - transverse output for a compressed gasket between the corrugations.

Claims (3)

The formula of the invention 1. A plate heat exchanger containing a supporting structure - a frame on which a package of corrugated plates is placed, each of the plates has inlet and outlet collector holes in the corner parts of the plate, plates - form two systems of channels in the heat exchanger, the heat exchange surface inside the channels is limited by the walls of the plates and nodes for sealing the channels along the contour of the plates and a pair of non-working corner holes, which differs in that the corrugations on one of the pairs of plates are located on one side and parallel to the longitudinal axis of the plate on the right and half of the plane of the plate, and the channels for the coolant are formed in a pair with the adjacent plate with inclined corrugations relative to the axis of the plate and on the entire plane of the plate, while on all plates the corrugations near the lateral longitudinal edges have different lengths, and in the cross section the corrugations have the shape of a triangle, the corners of which are rounded according to the radius of the circle, the center of which is distant from the apex triangle by the size of . M where n is the height of the corrugation. 2. The plate heat exchanger according to claim 1, which is characterized by the fact that in the inlet-outlet section for the flow of the heat carrier on each plate, the corrugations have a straight oblique shape, directed along the flow and connected without local hydraulic flow resistance near the collector holes and on the main surface of the plate heat exchange . - du 3. A plate heat exchanger according to claims 1, 2, which is characterized by the fact that the grooves for the elastic gasket on the plates along their contour and in the collector holes have transverse exits along the length of the groove periodically located through one corrugation, into which parts of the gasket are pressed when it is compressed in package of the plate :z" of the heat exchanger, and the width of the groove for the gasket in different parts of the plate is different, in places near the collector holes, the width of the groove is smaller than along the outer contour of the plate. se) (22) - Kz 50 Su; 60 b5