WO2014176194A1

WO2014176194A1 - Core device of a heat exchanger and heat exchanger with the core device

Info

Publication number: WO2014176194A1
Application number: PCT/US2014/034873
Authority: WO
Inventors: Zhenhua Zhang; Guoping Tian
Original assignee: Caterpillar Inc
Current assignee: Caterpillar Inc
Priority date: 2013-04-22
Filing date: 2014-04-22
Publication date: 2014-10-30
Anticipated expiration: 2015-10-22
Also published as: CN104110997A

Abstract

The present invention relates to a core device of a heat exchanger, comprising a plurality sets of paired plates, each pair being isolated by an elongated bar at at least one end side and forming a first passage therebetween for a first fluid; a plurality of spacer strips each disposed between two adjacent sets of paired plates to form a second passage for a second fluid therebetween extending transverse to the first passage, wherein the elongated bar has a flow-dividing flange protruding towards the outer side of the core device, the flow-dividing flange being adapted to direct the second fluid flowing towards the flow-dividing flange into the second passage. The present invention further relates to a heat exchanger having the core device.

Description

CORE DEVICE OF A HEAT EXCHANGER AND HEAT EXCHANGER WITH THE

CORE DEVICE

Technical Field

The present invention relates to a core device of a heat exchanger, and further to a heat exchanger provided with the core device.

Backfiround Art

Currently available plate-fin heat exchanger has been widely used as oil cooler, intercooler and water radiator in work machine, compression refrigerator and a generator set. Generally speaking, a core of a plate-fin heat exchanger is formed by long bars, short bars, baffles, inner fins and outer fins, wherein the inner fins, the baffles and the outer fins are stacked alternatively, and the outermost side of the core is fixed by a lateral baffle, the inner fins encloses with the long bars and the baffles at both sides to form heat side passages, the outer fins encloses with the short bars and the baffles at both sides to form cold side passages extending transverse to the heat side passages, and the cold side passages are usually used for flowing of cooling air.

Typically, the long and short bars of currently available plate-fin heat exchanger are designed to have a rectangular cross-section. Therefore, when cooling air is flowing to the cold side passage, a portion of the cooling air meets a planar outer surface of the long bar and is obstructed, which may be not favorable for subsequent air flowing and further reduces heat exchange coefficient at the air side. Also, a long bar having a rectangular cross-section is difficult to be assembled and positioned, which detrimentally affects temporary assembling of the heat exchanger.

The present invention therefore is intended to solve one or more problems in the prior art.

Summary of the Invention According to one aspect of the invention, a core device of a heat exchanger is provided, comprising a plurality of paired plates, each pair being isolated by an elongated bar at at least one end side and forming a first passage therebetween for a first fluid; a plurality of spacer strips each being disposed between two adjacent sets of paired plates to form a second passage for a second fluid therebetween extending transverse to the first passage, wherein the elongated bar has a flow-dividing flange protruding towards the outer side of the core device, the flow-dividing flange being adapted to direct the second fluid flowing towards the flow-dividing flange into the second passage.

According to a second aspect of the invention, a heat exchanger having the core device is provided.

Brief Description of the Drawiri S

The embodiments of the invention will be described below with reference to the figures, in which:

Fig. 1 is a general perspective view of the heat exchanger according to the invention;

Fig. 2 is a perspective view of a portion of the core device according to the invention;

Fig. 3 is a perspective view of a corner of the core device according to the invention;

Fig. 4 is a local sectional view of the core device according to the invention, showing a cross-section of the elongated bar between the paired plates of the core device according to the invention and a flowing path of the second fluid towards the second passage.

Detailed Description of the Embodiments Fig. 1 shows a heat exchanger 1 that may be mounted in a cooling package frame (not shown), the heat exchanger 1 comprising a core 100, which is sealingly welded with an inlet tank 211 and an outlet tank 212 at two opposite ends. A first fluid, such as oil, flows into an inlet tube 28 in fluid communication with the inlet tank 211 and flows out of the heat exchanger 1 via an outlet tube 29 in fluid communication with the outlet tank 222. A second fluid, such as cooling air, flows through the core 100 to cool the first fluid circulating in the core.

For the sake of easy illustration, the technical terms "upper side", "lower side", "left side", "right side" herein refer to the upper, lower, left and right directions in Fig. 2, and "front side" refers to a direction opposite to the direction indicated by the arrow A of Fig. 2, and "rear side" refers to the direction indicated by the arrow A of Fig. 2.

Specifically, as shown in Fig. 2, the core 100 comprises a plurality of paired plates 40, 40' placed vertically. An elongated bar 50 is disposed at ends of front and rear end sides of the paired plates 40, 40' and between the plates 40, 40' of each pair. The elongated bar 50 encloses with the plates 40, 40' at left and right sides thereof to form a first passage 101 for the first fluid, e.g. an oil to be cooled, extending in a vertical direction. An inner fin 10 extending in a waved manner is arranged within the first passage to enhance heat exchange coefficient of the first passage side, wherein the peak of each wave structure is connected to a plate 40 of the paired plates 40, 40' by means of e.g. brazing while the trough of each wave structure is connected to the other plate 40' of the paired plates 40, 40' by means of e.g. brazing, to divide the first passage 101 into a plurality of small flowing channels. A gap 60 is created by opposite plates 40, 40' between adjacent sets of paired plates 40, 40', and spacer strips 20 are provided at upper and lower end sides of the gap, thereby enclosing and forming a second passage 102 extending in a front-and-rear direction (the direction indicated by the arrow A) for the second fluid, e.g. cooling air. Similarly, an outer fin 30 extending in a waved manner is arranged within the second passage 102 to enhance heat exchange coefficient of the second passage 102 side, wherein the peak of each wave structure is connected to a plate 40 of the opposing plates by means of e.g. brazing, while the trough of each wave structure is connected to the other plate 40' of the opposing plates by means of e.g. brazing, to divide the second passage 102 into a plurality of small flowing passages. In addition, lateral plates 100a, 100b are provided at the outer sides of the plate 40' of at leftmost side and the plate 40 at the rightmost side, and correspondingly spacer strips 20 are disposed at upper and lower ends between the lateral plates 100a, 100b and the plates 40, 40' opposing the lateral plates to add a second passage for the second fluid and to protect the plates 40, 40' at the outermost side from damage caused by impact.

Further referring to Fig. 3, the outer fin 30 is not shown therein for a clear view. Fig. 3 shows the structure and mounting position of the elongated bar 50 in detail. A portion 501 of the elongated bar 50 is sandwiched between the paired plates 40, 40' to define a sealing wall surface of the first passage 101. The portion 501 is generally column shaped. A flow-dividing flange 50 protrudes from the portion 501 towards an outer side of the core 100. In a preferred embodiment, the flow-dividing flange 502 is designed to have a width generally tapering in a direction towards the outer side of the core device.

As shown in Figs. 3 and 4, the flow-dividing flange has a cross-section of arched shape. Those skilled in the art may envisage that the cross-section of the flow-dividing flange 502 may have a triangular shape or other irregular shapes, such as peach shape, tower shape and so on.

The portion 501 of the elongated bar 50 and the paired plates 40, 40' are in a sealed connection in an assembling state of the core 100. When the second fluid flowing towards the flow-dividing flange 502 (e.g. from the front side to the rear side of the core 100 in a direction indicated by the arrow A) meets a top 51 of the flow-dividing flange 502, the second fluid, due to blade-like action of the top 51, is separated at the top 51 of the flow-dividing flange 502 and flows into the second passage 102 at both sides of the elongated bar 50 along the side surface of the flow-dividing flange 502 to create a flow-dividing (diversion) structure in terms of hydrodynamics, so that more second fluids flow into the second passage.

Preferably, transition between the top 51 of the flow-dividing flange 502 and the side surface thereof is smooth such that the cross-section of the flow-dividing flange has a smooth arched profile, which is more advantageous for increasing flowing speed of the second fluid in the second passage and the heat exchange coefficient of the second passage side and for further enhancing heat exchanging coefficient of the entire core.

In a preferred embodiment, two lateral sides 502a, 502b of the flow-dividing flange 502 extend respectively in directions away from the portion 501 in a right-and-left direction, thereby forming shoulders 503a, 503b with the portion 501. As a result, the distance between edges of the two lateral sides 502a, 502b of the flow-dividing flange 502 in a right-and-left direction (i.e. width of the flow-dividing flange 502 at a side approximate to the paired plates 40, 40') is greater than width of the portion 501 in a right-and-left direction, as shown in Figs. 3 and 4. In an assembling state of the core 100, the plates 40, 40' that sandwiches the portion 501 abuts against the lateral sides 502a, 502b of the flow-dividing flange 502 at the shoulders 503a, 503b. The shoulders 503a, 503b are formed such that the elongated bar 50 is easily positioned during mounting thereof and such that the sealed connection between the elongated bar 50 and the plates 40, 40' is more tight and secure.

Preferable, a width of the flow-dividing flange 502 at a side approximate to the plates 40, 40' is equal to a corresponding distance at an end of the plates 40, 40' where shoulders 503a, 503b abuts on the outer side of the paired plates 40, 40' (with respect to the first passage 101). Hence, further, the second fluid will not be obstructed by the end face of the plates 40, 40' while flowing along the side surface of the flow-dividing flange 502 toward the inlet of the second passage 102 as indicated by the arrows of Fig. 4, but will directly flow through the inlet of the second passage, which is favorable for enhancing heat exchanging coefficient of the second passage side.

In order to facilitate welding, the elongated bar 50 is usually made from metal. In a preferred embodiment, the elongated bar 50 is integrally formed by the flow-dividing flange 502 and the column shaped portion 501. More preferably, the elongated bar 50 is integrally formed by extrusion molding so that it is possible to produce batches of elongated bars 50 and to improve production efficiency of the core. In addition, preferably, the elongated bar 50 is a solid rod-shaped member, so that the structure of the first passage 101 formed is increased to bear higher pressure and so that service life of the core is prolonged.

Furthermore, those skilled in the art may envisage that at least a portion of the spacer strip 20 may be configured as another flow-dividing flange having similar function as the one of the elongated bar to facilitate flowing of the first fluid into the first passage. Although in Figs. 2 and 3 the elongated bar at the front side of the core is taken as an example for illustration, those skilled in the art may easily envisage that it is possible to arrange, at any side of the core, an elongated bar having a flow-dividing flange protruding towards the outer side of the core, depending on the inflow direction of the second fluid. Industrial Applicability

The heat exchanger core disclosed herein is applicable to various work machines which are operating with the aid of a heat exchanger. The heat exchanger core disclosed exhibits high heat exchanging coefficient and prolonged service life and can be easily assembled and positioned to facilitate production of the heat exchanger in batches. The following is an introduction of the assembling process and operation principle of the heat exchanger core.

First, a plurality sets of paired plates 40, 40' are vertically provided, between each set of paired plates 40, 40' the inner fin 10 and the elongated bars 50 are inserted so that front and rear lateral edges of the plates 40, 40' abut against shoulders 503a, 503b of the elongated bars 50 to form a first passage 101 extending in a vertical direction. Then, the outer fin 30 and the spacer strips 20 are inserted into a gap 60 between two adjacent sets of paired plates to form a second passage 102 extending in a front-and-rear direction. And then lateral plates 100a, 100b are placed vertically at the outer side of the outermost plates 40, 40', and the spacer strips 20 and the outer fins 30 are placed in the gap between the lateral plates and the outermost plates to form additional second passages. Finally, the whole temporarily assembled core 100 is subject to vacuum brazing to produce a secure heat exchanger core.

Subsequently, the inlet tank 211 and the outlet tank 212 are welded to upper and lower ends of the core 100 to fluidly communicate the inlet tank 211 and the outlet tank 212 with the first passage 101 of the core 100 into which a first fluid from the inlet tank 211 flows via an upper inlet of the first passage 101 and exchanges heat with the second fluid flowing through the second passage 102 of the core 100 by means of the plates 40, 40'. At last, the first fluid through the heat exchanger flows from the first passage 101 into the outlet tank 212 and discharges from the outlet tank 212 into a circulating system.

A variety of work machines such as hydraulic evacuator, wheeled loader, off-road truck, wheeled traction scraper and so on may benefit from application of the heat exchanger core disclosed herein.

The above depiction is only preferred embodiments of the present invention and is not taken as limiting or restricting this invention since various modifications and variations may be made without departing from the scope of the device through the exercise of those skilled in the art. Other embodiments may be obtained on the basis of disclosure in the description. The description and embodiments shall be considered exemplary only and the true scope of the invention is defined by the annexed claims and equivalents thereof.

Claims

1. A core device of a heat exchanger, comprising a plurality of paired plates , each pair being isolated by an elongated bar at at least one end side and forming a first passage therebetween for a first fluid; a plurality of spacer strips each disposed between two adjacent sets of paired plates to form a second passage for a second fluid therebetween extending transverse to the first passage, wherein the elongated bar has a flow-dividing flange protruding towards the outer side of the core device, the flow-dividing flange being adapted to direct the second fluid flowing towards the flow-dividing flange into the second passage.

2. The core device according to claim 1, characterized in that a width of a portion of the elongated bar sandwiched between the paired plates is smaller than a width of a side of the corresponding flow-dividing flange approximate to the paired plates.

3. The core device according to claim 2, characterized in that a distance at the end side of the paired plates between two outer sides of the two plates of the paired plates is equal to a width of a side of the corresponding flow-dividing flange approximate to the paired plates.

4. The core device according to any one of claims 1-3, characterized in that the flow-dividing flange has a width tapering in a direction towards the outer side of the core device.

5. The core device according to any one of claims 1-4, characterized in that the flow-dividing flange has a cross-section of an arched shape, a triangular shape, a peach shape, and a tower shape.

6. The core device according to any one of claims 1-5, characterized in that the elongated bar is made from metal by extrusion molding.

7. The core device according to any one of claims 1-6, characterized in that the elongated bar is a solid rod-shaped member.

8. The core device according to any one of claims 1-7, characterized in that the first fluid is oil or water, and the second fluid is cooling air.

9. The core device according to any one of claims 1-8, characterized in that at least a portion of the spacer strip is configured as another flow-dividing flange protruding towards the outer side of the core device, the another flow-dividing flange being adapted to direct the first fluid flowing towards the another flow-dividing flange into the first passage.

10. A heat exchanger comprising a core device according to any one of claims 1-9.