ES2279713B1 - HEAT EXCHANGER OF STACKED PLATES. - Google Patents

Abstract

Stacked plate heat exchanger. It comprises a body (2) that defines a U-shaped trajectory, intended for the circulation of gases with heat exchange with a cooling fluid, whose inlet (3) and outlet (4) of the gases to be cooled are arranged adjacent one on top of the other, said body (2) comprising two parallel and independent sections, upper (2a) and lower (2b), provided with a plurality of stacked plates (5). It is characterized by the fact that the plates (5) are closed at their end (6) and include near said end (6) a through hole (7) defining the return path of the gas from the upper plate section (2a) to the lower plate section (2b), or vice versa, said hole (7) being closed by an upper plate (8) and a lower plate (9). The heat exchanger obtained does not need to use a gas tank to carry out the return of the gas.

Description

Stacked plate heat exchanger.

The present invention relates to a stacked plate heat exchanger, of the type comprising a body that defines a "U" shaped path, intended for the circulation of gases with heat exchange With a cooling fluid.

The invention especially applies to Exhaust gas recirculation exchangers of an engine (Exhaust Gas Recirculation Coolers or EGRC); and refrigerators supercharger air or intercoolers (Charge Air Coolers or CAC).

Background of the invention

The "U" configuration of the EGR type exchangers is often used for reasons of integration. In addition, this configuration increases performance specific heat exchanger (volume efficiency), although the pressure loss also increases. Also said configuration allows easy integration of a by-pass, with the corresponding valve by-pass arranged in the entrance area of the gas.

In a stacked plate exchanger, the "U" shaped flow can be created according to one direction horizontal or vertical. The horizontal direction means that the gas Enter the exchanger on the left side and exit on the side right (or vice versa). This can be done through a tank at the end end of the plates, which conducts the gas from left to right, or by means of a specific form of a disturbing. In this case, the plates are closed at the end end, said end end preferably having a shape rounded. The disturber does not reach the end end leaving space for the "U" return of the gas. The disturber can understand independent channels, such as channels with triangular shape, so that the gas does not flow freely from the left on the right, or an offset (offset) perturbator with a channel I continue in the center.

On the other hand, the vertical direction means that the gas enters the exchanger from the upper side and leaves from the bottom side (or vice versa).

However, the vertical direction of the flow in "U" can only be carried out through a deposit that conducts the gas from the upper plates to the lower ones, or vice versa.

Description of the invention

The purpose of the heat exchanger of stacked plates of the present invention is to solve the drawbacks cited, providing a heat exchanger in U-shaped vertical configuration that you don't need use a gas tank to carry out the return of the gas.

The stacked plate heat exchanger, especially of the exhaust gases of an engine, of the present invention is of the type comprising a body that defines a U-shaped trajectory, intended for the circulation of heat exchange gases with a cooling fluid, whose inlet and outlet of the gases to be cooled are arranged adjacent one on top of the other, said body comprising two parallel and independent sections, upper and lower, provided of a plurality of stacked plates, and is characterized by the fact that the plates are closed at their end and include near said end a through hole defining the return path of the gas from the plate section greater than lower plate section, or vice versa, said hole remaining closed by an upper plate and a lower plate.

In this way, an exchanger of heat of stacked plates, U-shaped configuration vertical, you do not need to use a gas tank to carry out the return of the gas, with the consequent reduction of the cost and the decrease in the total volume of the exchanger.

Advantageously, each plate includes an element gas flow disruptor.

According to an embodiment of the present invention, each section of upper and lower plates includes a type of different disturbing element.

According to another embodiment of the present invention,  each section of upper and lower plates includes a type of Different cooling fluid circuit.

Advantageously, the transverse surface of the hole is approximately equal to the transverse surface of the gas inlet, so that the pressure drop does not increase considerably.

Additionally, the exchanger comprises a gas tank attached to the entrance and exit zone of the Exchanger gases.

Preferably, the gas tank has a  noticeably orthogonal configuration including a hole upper that allows the entry of gases according to a direction noticeably perpendicular to the plates, and a front hole that allows the exit of gases according to a direction substantially parallel to the plates.

Advantageously, the exchanger includes a by-pass valve that allows to open or close the passage of the gases to the exchanger.

Also advantageously, the valve by-pass is integrated in the gas tank itself of the exchanger.

According to an embodiment of the invention, the Bypass valve is a butterfly valve.

In this case, preferably, the valve by-pass comprises a plate articulated to an axis centrally located between the entrance and exit areas of the respective sections of upper and lower plates, so that when the valve is open the plate is arranged in a parallel position to the plates allowing the entry and exit of the gases, and when the valve is closed the plate is arranged in an inclined position in which the plate allows to seal the holes in and out of the gas tank.

Brief description of the drawings

In order to facilitate the description of how much  It has been exposed above are attached some drawings in which, schematically and only by way of non-limiting example, represents a practical case of realization of the exchanger of heat of stacked plates of the invention, in which:

Figure 1 is a longitudinal section view  of the heat exchanger in "U" according to the direction vertical;

Figure 2 is a perspective view of the exchanger of figure 1, without the top plate to be able to display the gas return hole; Y

Figure 3 is a perspective view of the heat exchanger with two different refrigerant circuits according to another embodiment of the invention.

Description of a preferred embodiment

As can be seen in figures 1 and 2, the stacked plate heat exchanger 1, especially those exhaust gases of an engine, comprises a body 2 that defines a U-shaped trajectory, intended for the circulation of heat exchange gases with a cooling fluid, whose inlet 3 and outlet 4 of the gases to be cooled are arranged adjacent one on top of the other, said body 2 comprising two parallel and independent sections, upper 2a and lower 2b, provided with a plurality of stacked plates 5.

The plates 5 are closed at their end 6 and include near said end 6 a through hole 7 which defines the return path of the gas from the plate section upper 2a to the lower plate section 2b, said hole remaining 7 closed by an upper plate 8 and a lower plate 9.

Figure 2 has not shown the plate top 8 to be able to display the appropriate configuration of the hole 7 which must allow the return of the gas from the section of upper plates 2a to the lower plate section 2b, and at the same time, minimize the gas pressure drop.

Also, each plate 5 includes an element disruptive (not represented for reasons of clarity) of the flow of gas. These disturbing elements do not reach the final end 6 of the plates 5 to allow the return of the gas through the cited hole 7.

As can be seen in Figure 1, the exchanger 1 is coupled in the input and output zone of gases to a gas tank 10. According to an embodiment of the invention, the gas tank 10 comprises an upper hole 3 which allows the entry of gases according to a direction substantially perpendicular to the plates 5, and a front hole 4 which allows the exit of gases according to a direction substantially parallel to the plates 5.

It should be noted that obviously there may be other embodiments of the gas tank, such as the input 3 is parallel to plates 5 and output 4 perpendicular to the same; or that input 3 and output 4 are both parallel or both perpendicular to plates 5, among other configurations possible.

The exchanger 1 also comprises a bypass valve 11, integrated in the tank itself of gas 10, which allows to open or close the passage of gases towards the exchanger 1.

According to an embodiment of the invention, and according to it can be seen in figure 1, the by-pass valve it is of the butterfly type, and comprises a plate 11 articulated to an axis centrally located between the entrance and exit areas of the respective sections of upper plates 2a and lower 2b. Of this mode, when the valve is open the plate 11 is arranged in a position parallel to the plates 5 allowing entry and gas outlet; and when the valve is closed plate 11 it is arranged in an inclined position in which the plate 11 it allows to seal the entrance 3 and exit 4 holes of the tank of gas 10, so that input 3 and output 4 are connected each other, giving rise to the by-pass function proper, in which the gases pass directly to the Exhaust line without being cooled by the exchanger.

The operation of the exchanger is the next:

With valve 11 open, the gas enters the heat exchanger 1 towards the upper plate section 2a a through the respective disturbing elements until reaching the final end 6 of the plates 5, going through the hole 7. Said hole 7 causes the return of the gas flow that is now directed towards the lower plate section 2b crossing the respective disturbing elements, and finally leaves the exchanger 1 heading towards the gas recirculation line.

The arrows represented in figure 1 show the direction of gas flow through the exchanger one.

The design of the plates 5 provided with the said hole 7 prevents the use of a gas tank conventional, which is usually a complicated piece of manufacturing and relatively expensive in exchangers with a high number of plates.

In addition, the design of the plates 5 is also very  versatile, since the same plate 5 can be used to exchangers of different number of plates, and only the connecting parts to the entrance area should be modified and Exchanger output.

This type of plates 5 allows manufacturing very simple of asymmetric U-shaped exchangers since only the connection parts to the entrance and exit area of the exchanger. The configuration of said connection pieces determines how many plates the gas will use to enter the exchanger and exit it. The number of gas inlet plates may be higher than the number of plates for the gas outlet, which is very convenient because to the increase in gas density through the exchanger while It is cooling.

The configuration of exchanger 1 of the invention is very versatile, since there can be two elements different disruptors in the exchanger, an element disruptor to the plates where the gas is hot, and a denser disturbing element for the plates where the gas is colder and has a higher density. In this case, the efficiency of the exchanger increases without increasing its volume.

According to another embodiment of the invention, the exchanger can include two refrigerant circuits different. In figure 3 it can be seen as the exchanger It includes the corresponding refrigerant circuit for each refrigerant circuit inlet ducts 12a, 13a and outlet ducts 12b, 13b respectively. The high temperature refrigerant circuit can cool the plates where the gas is hot and the refrigerant circuit of Low temperature can cool the plates where the gas is cold. In this case, the efficiency of the exchanger also increases without increase its volume

All these possibilities can be combined easily, further increasing efficiency, or allowing the design of a smaller exchanger to achieve them efficiencies.

Claims (11)

1. Heat exchanger (1) of stacked plates, especially the exhaust gases of an engine, comprising a body (2) that defines a "U" shaped path, intended for the circulation of gases with exchange of heat with a cooling fluid, whose inlet (3) and outlet (4) of the gases to be cooled are arranged adjacent one above the other, said body (2) comprising two parallel and independent sections, upper (2a) and lower (2b), provided with a plurality of stacked plates (5), characterized in that the plates (5) are closed at their end (6) and include near said end (6) a through hole (7) defining the return path of the gas from the upper plate section (2a) to the lower plate section (2b), or vice versa, said hole (7) being closed by an upper plate (8) and a lower plate (9) . 2. Exchanger (1) according to claim 1, characterized in that each plate (5) includes a disturbing element of the gas flow. 3. Exchanger (1) according to claim 2, characterized in that each section of upper (2a) and lower (2b) plates includes a different type of disturbing element. 4. Exchanger (1) according to any of the preceding claims, characterized in that each section of upper (2a) and lower (2b) plates includes a different type of cooling fluid circuit. 5. Exchanger (1), according to any of the preceding claims, characterized in that the transverse surface of the hole (7) is approximately equal to the transverse surface of the gas inlet (3). 6. Exchanger (1), according to any of the preceding claims, characterized in that it comprises a gas tank (10) coupled in the inlet and outlet zone of the exchanger gases (1). 7. Exchanger (1) according to claim 6, characterized in that the gas tank (10) has a substantially orthogonal configuration including an upper hole (3) that allows the entry of gases according to a direction substantially perpendicular to the plates (5), and a front hole (4) that allows the gases to exit in a direction substantially parallel to the plates (5). 8. Exchanger (1), according to any of the preceding claims, characterized in that it includes a by-pass valve (11) that allows to open or close the passage of gases to the exchanger (1). 9. Exchanger (1) according to claim 8, characterized in that the bypass valve (11) is integrated in the gas tank (10) of the exchanger (1). 10. Exchanger (1) according to claim 8 or 9 characterized in that the bypass valve (11) is a butterfly valve. 11. Exchanger (1) according to claim 10, characterized in that the bypass valve comprises a plate (11) articulated to an axis centrally located between the inlet and outlet zones of the respective upper plate sections (2a) and lower (2b), so that when the valve is open the plate (11) is arranged in a position parallel to the plates (5) allowing the entry and exit of gases, and when the valve is closed the plate (11) is arranged in an inclined position in which the plate (11) allows to seal the inlet (3) and outlet (4) holes of the gas tank
(10)