Patent Document

FIELD OF THE INVENTION 
       [0001]    The present invention is directed to the field of heat exchangers; and more particularly to heat exchangers having flow directors for directing the flow of fluids to one or more portions of the heat exchanger. 
       BACKGROUND OF THE INVENTION 
       [0002]    Often, an operating machine, electronic component or other system generates waste heat in the course of its normal operation. If this waste heat is not removed, degraded performance or damage to the system may result. Frequently, the operating temperature of a system needs to be precisely maintained in order to obtain optimal performance. For example, it is often desirable to cool the sensors used in thermal imaging cameras to improve the sensitivity of the imager. Further, analytical instruments may require that the sample to be analyzed be presented to the instrument at a precisely controlled temperature. 
         [0003]    Heat exchangers permit heat to be removed from or added to the sample as may be desired. A common type of heat exchanger is referred to as a “heat sink.” A heat sink typically transfers heat between a solid object and some fluid media, which may be a liquid, air or other gas. Computer microprocessors frequently employ heat sinks to draw heat from the processor to the surrounding air, thereby cooling the microprocessor. Such a heat sink could also comprise a closed fluid system. For example, a recirculating liquid coolant might be used to transfer heat from that portion of the heat sink in contact with the heat-generating device to a remotely located radiator. Regardless of the type of heat exchanger, it is desirable to obtain a high degree of heat transfer efficiency. 
         [0004]    Fluid flow should be efficient with minimal pressure loss and with fluid dynamics that promote efficient heat transfer. Additionally, other important criteria are known and will not be detailed here. Typically a heat exchanger comprises a heat exchanging element and some means of controlling the flow of the heat-exchanging medium. Frequently this medium is a gas or liquid. Flow channels may be provided to control fluid flow and promote efficient heat transfer between the heat exchanging element and the heat exchanging fluid. Particularly in the case of liquid mediums, an inlet and an outlet manifold is often provided so that the liquid may be readily coupled via a hose or pipe that may be connected to a recirculating pump or other pressure source. 
         [0005]    An example of this type of heat exchanger is that of an automobile radiator. Inside the radiator is a plurality of water cooling channels coupled to heat conducting fins. Air is forced across the fins to cool the water inside. The water is then circulated throughout the engine block to cool the engine. A typical automobile radiator comprises a vertical water inlet tube that services a plurality of horizontal cooling channels. Similarly, a vertical water outlet tube collects water from these channels. The inlet and outlet tubes are typically at right angles to the cooling channels. Usually hydraulic pressure is relied on to force the water to make the 90 degree angle change as it flows from the inlet tube and into the cooling tubes, and again as it flows from the cooling tubes into the outlet tube. While this method of flow re-direction is inefficient, it constitutes a relatively minor energy drain with respect to powering the automobile. However, as energy costs escalate and products become ever more competitive, such inefficiencies are no longer acceptable. 
         [0006]    The heat exchanger and the method of making the heat exchanger of the present invention overcome many of the shortcomings of previous designs, particularly with respect to hydraulic efficiency, the transition of fluid flow between the inlet and outlet manifolds, and the heat exchanger proper. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention describes a heat exchanger and method of making the heat exchanger, having flow directors for directing the flow of fluids to one or more portions of the heat exchanger. In an illustrative embodiment, the heat exchanger having flow directors comprises a main body adapted for heat exchange having a plurality of channels adapted to receive fluid flow. The main body has a first wall and a back wall sized and shaped to contain fluid flow therein. The heat exchanger also includes a plurality of heat exchanging elements positioned between the front wall and the back wall to form at least one fluid flow channel. Each of the heat exchanging elements has a length that traverses the length of the main body. At least one flow director is adapted for directing fluid flow, and at least one fluid manifold is adapted for receiving fluid from an external source. Fluid from an external source is directed to the fluid flow channels whereby hydraulic efficiency is maximized, i.e. reducing pressure drop, by preventing fluid turbulence associated with non-directed flow of fluid within. 
         [0008]    A significant advantage of the present invention is the ability to readily create integral flow directors in a heat exchanger. Moreover, the flow directors may take on a variety of shapes and curvatures as may be desired to promote efficient fluid direction change in a heat exchanger. A further advantage of the instant invention is that the flow directors may be formed without the use of additional parts, or without the requirement for additional processing steps. The heat exchanging device with flow directors may also be formed by a highly scalable process, thereby permitting heat exchangers of any size to be produced. 
         [0009]    Accordingly, it is an objective of the present invention to provide a heat exchanging device that reduces the amount of turbulence in the inlet and/or outlet manifold associated with fluid flow therein. 
         [0010]    It is a further objective of the present invention to provide a heat exchanging device that increases hydraulic efficiency and the transition of fluid flow between the inlet and outlet manifolds and the heat exchanger proper. 
         [0011]    It is yet another objective of the present invention to provide a heat exchanging device having integral flow directors. 
         [0012]    It is a still further objective of the present invention to provide a heat exchanging device having integral flow directors adapted to direct fluid flow to one or more heat exchanging channels, thereby providing a more even flow distribution between heat exchanger elements. 
         [0013]    It is a further objective of the present invention to teach a process whereby heat exchangers incorporating integral flow directors may be simply and economically produced. 
         [0014]    It is yet another objective of the present invention to teach a process that provides a heat exchanging device having integral flow directors which is readily adaptable to modern manufacturing processes. 
         [0015]    Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with any accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. Any drawings contained herein constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0016]      FIG. 1  is a front perspective view of an illustrative example of a heat exchanging device with flow directors in accordance with the present invention; 
           [0017]      FIG. 2  is a back perspective view of the heat exchanging device with flow directors in accordance with the present invention; 
           [0018]      FIG. 3  is a perspective view of the heat exchanging device with flow directors with inlet and outlet manifolds; 
           [0019]      FIG. 4A  illustrates a heat exchanging device with flow directors in accordance with the present invention with the upper wall removed to show the arrangement of the internal components; 
           [0020]      FIG. 4B  illustrates the flow of fluid within the heat exchanging device with flow directors shown in  FIG. 4A ; 
           [0021]      FIG. 4C  is an exploded view of the flow directors formed from a series of multiple stacked laminar plates to form a particular three dimensional shape; 
           [0022]      FIG. 5A  is a perspective view of an illustrative example of a flow director; 
           [0023]      FIG. 5B  is a perspective view of an alternative embodiment of a flow director; 
           [0024]      FIG. 5C  is a perspective view of an alternative embodiment of a flow director; 
           [0025]      FIG. 5D  is a perspective view of an alternative embodiment of a flow director; 
           [0026]      FIG. 5E  is a perspective view of an alternative embodiment of a flow director having a generally “C” shape; 
           [0027]      FIG. 6A  is a perspective view of a first manifold laminar plate of an inlet manifold; 
           [0028]      FIG. 6B  is a perspective view of a second manifold laminar plate of an inlet manifold; 
           [0029]      FIG. 6C  is a perspective view of a third manifold laminar plate of an inlet manifold; 
           [0030]      FIG. 6D  is a perspective view of a fourth manifold laminar plate of an inlet manifold; 
           [0031]      FIG. 6E  is a perspective view of a fifth manifold laminar plate of an inlet manifold; 
           [0032]      FIG. 7  is a front perspective view of an alternative embodiment of a heat exchanging device with flow directors in accordance with the present invention; 
           [0033]      FIG. 8A  illustrates the heat exchanging device with flow directors shown in  FIG. 7  with the upper wall removed to show the arrangement of the internal components; 
           [0034]      FIG. 8B  illustrates the flow of fluid within the heat exchanging device with flow directors shown in  FIG. 8A ; 
           [0035]      FIG. 9  is a perspective view of the heat exchanging device with flow directors shown in  FIG. 7  after the extrusion process, illustrating the initial step of forming finger like flow directors; 
           [0036]      FIG. 10  is a front view of the heat exchanging device with flow directors shown in  FIG. 9 ; 
           [0037]      FIG. 11  is a perspective view of the heat exchanging device with flow directors shown in  FIG. 9 , illustrating removal of a portion of the heat exchanging main body. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0038]    While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred, albeit not limiting, embodiment with the understanding that the present disclosure is to be considered an exemplification of the present invention and is not intended to limit the invention to the specific embodiments illustrated. 
         [0039]    Referring to  FIG. 1 , a perspective view of an illustrative embodiment of a heat exchanging device with flow directors, referred to generally as  10 , is illustrated. The heat exchanging device with flow directors  10  contains a main body  12 , preferably made of a laminar material and/or other materials that exchange heat such as metals, including aluminum copper, nickel, brass or stainless steel, ceramics, plastics, glass, or other suitable materials which act as a heat exchanging element. The main body  12  may be formed by an extrusion process, though other methods known to one of skill in the art may also be employed. The main body  12  is defined by a top wall  14 , a bottom wall  16 , two side walls  18  and  20 , a first end  22 , and a second end  24 . The distance between the first end  22  and the second end  24  defines the length of the heat exchanging device with flow directors  10 . 
         [0040]    As shown in  FIGS. 1 and 2 , the first end  22  contains a substantially cylindrically shaped first manifold, an inlet manifold  26 , integrally formed or attached thereto. The inlet manifold  26  contains a first open end  28  sized and shaped to allow fluid from an external source, such as a liquid or a gas, to enter therein, a second closed end  30 , and a manifold body  32  there between. The second end  24  of the heat exchanging device with flow directors  10  may be open to allow fluid that has entered into and flowed within the main body  12  to exit. The inlet manifold  26  is provided to facilitate coupling of fluid inlet lines, such as hoses, tubes or pipes, or other conduits to the heat exchanger. While the inlet manifold  26  is shown having a generally cylindrical shape, any shape may be used. 
         [0041]    The heat exchanging device with flow directors  10  may also contain a second manifold, an outlet manifold  34 , integrally formed or attached to the second end  24 , see  FIG. 3 . The outlet manifold  34  as shown includes a first open end  36  which is sized and shaped to allow fluids, such as a liquid or a gas, to exit the main body  12 , a second end  38  which is closed, and an outlet manifold body  40 . While the outlet manifold  34  is shown having the first end  36  being open, it is within the scope of this invention that the second end  38 , or both ends  36  and  38  contain an opening for exiting fluid flow. The outlet manifold  34  is provided to facilitate coupling of outlet lines, such as hoses, tubes or pipes, or other conduits from the heat exchanger. While the outlet manifold  34  is shown having a generally cylindrical shape, other shapes may be used. 
         [0042]    Referring to  FIG. 4A , an illustrative embodiment of the heat exchanging device with flow directors  10  is shown. The upper wall  14  has been removed in order to illustrate the inner components and arrangement thereof. In addition, the outlet manifold  34  has been removed. The main body  12  is adapted to provide fluid containment by having a first proximal wall  42  and a second distal wall  44 . Both the first proximal wall  42  and the second distal wall  44  traverse the length of the heat exchanging device with flow directors  10 , and have a height which extends from the inner surface  46  of the bottom wall  16  to the inner surface of the top wall  14  (not illustrated). The first proximal wall  42  and the second distal wall  44  function to contain and confine a heat exchanging fluid, such as a liquid or a gas, to the interior  48  of the heat exchanging device with flow directors  10 . 
         [0043]    Placed within the interior  48  are one or more heat exchanging elements, illustrated as heat exchanging fins  50 A- 50 D, collectively referred to as fins  50 . The fins  50  are preferably made of metal having heat conductive properties such as aluminum or copper. The fins  50  are arranged in a substantially parallel manner relative to each other and traverse the distance of the main body  12 , i.e. run from the first end  22  to the second end  24 . Alternatively, the fins  50  may be arranged in a discontinuous manner, having a fin which extends a predetermined distance, followed by a predetermined distance with no fin structure. The alternating pattern of fin structure/no fin structure can be repeated along the length of the main body  12 . Accordingly the heat exchanging fin  50 A is aligned in a substantially parallel manner with the heat exchanging fin  50 B. Such arrangement provides for the formation of one or more fluid channels  52 . Each of the fins  50  has a length that traverses the length of the main body, running from the first end  22  to the second end  24 . The height of each fin extends from the inner surface  46  of the bottom wall  16  to the inner surface of the top wall  14  (not illustrated). The positioning of each of the fins  50 , as well as the physical characteristics, i.e. the height and length, provide individual channels for directional flow of fluid within the main body  12  of the heat exchanger  10 , and act as a thermally conductive path. Each of the channels  52  formed are defined by the space between at least one fin and 1) a second fin, 2) the proximal wall, or 3) the distal wall. Additionally, the fins  50  provide a thermally conductive path to the heat exchanger main body  12 . These elements promote controlled fluid flow and serve to prevent dead spots or undesirable circulating eddies. 
         [0044]    While providing flow distribution with the heat exchanger in this manner reduces the likelihood of excess and insufficient flow zones, one problem not addressed is the flow rate and/or flow distribution of fluids prior to reaching the channels  52 . To overcome such problems, the heat exchanger with flow directors  10  in accordance with the present invention utilizes one or more flow directors  54  positioned within or extending into the inlet manifold  26 , the outlet manifold  34 , or combinations thereof. The embodiment of the heat exchanger with flow directors  10  illustrated in  FIG. 4A  shows flow directors (individually as  54 A,  54 B,  54 C, and  54 D) formed as part of or positioned on the interior surface  58  of the interior  60  of the inlet manifold  26 . In this manner, directional flow of fluid entering into the heat exchanger with flow directors  10  can be directed to one or more of the fluid flow channels  52 . Referring to  FIG. 4B , fluid entering into the opening  28  of the inlet manifold  26  is directionally diverted into particular flow channels  52 . 
         [0045]    To achieve the directional diversion of fluid, the flow directors  54  are adapted and positioned to direct the fluid flow accordingly. As fluid is introduced into the inlet manifold  26 , see arrow  61  on  FIG. 4B , the fluid flow path  62  in the inlet manifold  26  is initially and predominantly in the direction of the longitudinal axis  64  (see  FIG. 1 ) of the inlet manifold  26 . At least one of the flow directors  54  is employed to urge the fluid from this path and into heat exchanging body  12 . 
         [0046]    Referring to  FIG. 5A , as an illustrative example, the flow directors  54  have a first end  66  positioned to align with one end of a heat exchanger fin  50 , a second end  68  aligned with the fluid flow path  62  of the inlet manifold  26 , and a flow director body  70 . The flow director body  70  has an inner surface  72  for contacting and diverting fluid into a channel  52  and a second outer surface  74  for contacting and diverting fluid flow along the longitudinal axis  64  (see  FIG. 1 ) of the inlet manifold  26 . As shown in  FIGS. 4A and 4B , the flow director body  70  is arranged in a generally parallel arrangement to the longitudinal axis  64  and spaced apart from other flow director bodies  70 . This arrangement allows each flow director  54 A- 54 D to be arranged in a step-like fashion along the interior surface  60  of the inlet manifold  26 , each being parallel to the preceding flow director  54 . Alternatively, the flow directors  54  can be arranged to have a more diagonal orientation. Preferably, the flow directors  54  have a curved surface  76  to provide gradual and efficient re-direction of fluid flow direction so that fluid entering the heat-exchanging element becomes aligned with the flow channels  50 , thereby minimizing hydrodynamic pressure losses. 
         [0047]    The degree of curvature may vary depending on the type of fluid flow and other characteristics needed with respect to the exchange of heat per application. For example, the curvature may form an angle α between greater than 0 degrees and less than 180 degrees, preferably approximately 90 degrees. Without these flow directors, the fluid in the fluid manifold  15  tends to continue in a straight path parallel to the longitudinal axis of the fluid manifold until the fluid reacts with the distal wall  44 . This reaction generates a great deal of turbulence, resulting in hydraulic inefficiency. Further, the fluid flow is now such that a disproportionate volume of fluid flows into the fluid channel nearest the distal wall  44 . This disproportionate flow results in uneven heat transfer and potential hot spots in the heat exchanger, and similarly the device to be cooled or heated. A further advantage of the application of the flow directors is in the reduction of mechanical wear on the heat exchanger and the fluid manifold. Such wear is aggravated by turbulent flow, cavitation and high-pressure fluid impact on the components of the system. The present design serves to minimize these negative effects. 
         [0048]    Each flow director  54  may be preformed as a single unit, sized to have a predetermined height. Alternatively, each flow director  54  may be formed by multiple stacked, laminar flow director elements or platelets secured together to form an overall three dimensional shape. Referring to  FIGS. 4A-4C , flow director  54  are made of a plurality of laminar flow director elements or platelets. As an illustrative example, the flow director  54 C is made up of two flow director laminar elements or platelets  54 C′ and  54 C″. While the Figure illustrates two flow director laminar elements or platelets, any number may can be used to make the structure. The multiple stacked, laminar elements or platelets  54 C′ and  54 C″ can be assembled by brazing or other suitable means and may be produced simultaneously with the formation of the inlet manifold  26 , as will be described later. Each of the other flow directors  54 A- 54 D are constructed in the same manner. To aid in the alignment and construction, each of the flow director  54  are secured by support structures, illustrated herein as stringer  55 , see  FIG. 4C . All or portions of the stringer  55  may be removed to form the final configuration in order to allow proper fluid flow. Otherwise, the strangers  55  are configured to provide optimal fluid flow. The net shape of the flow directors  54 , therefore, can be easily and precisely controlled by defining the shape of the individual laminar elements or platelets from which they are comprised. Individual platelet formation is usually accomplished by photochemical machining, fine blanking, laser or water jet cutting or other known processes. 
         [0049]    While the shape of the flow directors  54  illustrated shows a square leading edge  78  at the first end  66  and a trailing edge  80  at the second end  68 , the leading and trailing edges and indeed the entire director can take any form desired which provides one fluid flow directional change, such as but not limited to a wedge  82 , see  FIG. 5B , teardrop  84 , see  FIG. 5C , a complex curve  86 , see  FIG. 5D . In this example, the form of the directors is readily controlled by defining the shape of the platelets from which it is comprised. Additionally, the overall shape of the flow directors  54  may have a generally “C” shape, see  FIG. 5E . In any configuration, the flow directors  54  are preferably configured to provide a directional fluid flow change with respect to the original fluid flow path entering, exiting, or combinations thereof, the heat exchanging device with flow directors  10 . 
         [0050]    The manifold inlet  26  illustrated in  FIGS. 4A ,  4 B and  4 C is constructed of multiple, stacked manifold laminar plates  88 ,  90 ,  92 ,  94 , and  96  that, when combined, produce the desired net overall shape, for example a generally cylindrical shape. The plates  88 - 96  may have individual features that contribute to the overall shape and functional features of the inlet manifold  26 . For example, the manifold laminar plate  88  may be constructed to contain a single solid, planar surface  98  having no surface configurations, see  FIG. 6A . The manifold laminar plate  90  may contain a planar surface  100  having a cut-out portion  102 . See  FIG. 6B . The manifold laminar plate  92  may contain a planar surface  104  having a cut-out portion  106 , see  FIG. 6C , that is wider than the cut out portion  102 . 
         [0051]    The manifold laminar plate  94  may contain a planar surface  108  having a cut-out portion  110  that is wider than the cut out portion  106 . The manifold laminar plate  94  contains one or more flow director laminar elements or platelets  54 A″,  54 B″,  54 C″, and  54 D″. The flow director laminar elements or platelets  54 A″,  54 B″,  54 C″, and  54 D″ are preferably formed as an integral part of the plate  94 , but may be formed independently and attached thereto. The manifold laminar plate  96  may contain a planar surface  114  having a cut-out portion  116  that is wider than the cut out portion  110 . Additionally, the planar surface  114  may contain one or more flow director laminar elements or platelets  54 A′,  54 B′,  54 C′, and  54 D′. The flow director laminar elements or platelets  54 A′,  54 B′,  54 C′, and  54 D′ are preferably integrally formed with the plate  94 , but may be formed independently and attached thereto. 
         [0052]    Alignment or positioning of the flow director laminar elements or platelets  54 A′,  54 B′,  54 C′, and  54 D′ allows for alignment with and proper positioning with respect to the flow director laminar elements or platelets  54 A″,  54 B″,  54 C″, and  54 D″ so as to provide a stacked unit which forms the flow directors  54 . This configuration allows for the flow directors  54  to form three dimensional structures having a desired shape. Accordingly, placing manifold laminar plate  96  on top of the manifold laminar plate  94  forms a plurality of stacked, laminar elements or platelets to form the flow directors  54 . As shown in  FIGS. 4A and 4B , the cut out portions create a stepped region at the opening  28 , formed by each successive manifold laminar plate forming a cantilevered area  120  relative to the preceding plate. The upper portion of the inlet manifold  26  may be formed as a mirror image of the lower portion just described. 
         [0053]    The multiple, stacked manifold laminar plates  88 ,  90 ,  92 ,  94 , and  96  may be bonded, joined or otherwise affixed to one another by a variety of processes. A suitable method to bond the manifold laminar plates is by soldering, brazing or diffusion bonding. If soldering or brazing is to be employed, the soldering or brazing alloy may be applied to one or both of the faces to be bonded. Further, the soldering or brazing alloy may be in the form of cladding or a plated layer on the laminar material, which when heated, bonds the adjacent layers. Brazing may also be accomplished by “dip-brazing” or other suitable processes as long as the process does not significantly interfere with desirable fluid path geometries. In lieu of or in addition to bonding adjacent layers by diffusion bonding or brazing, any suitable welding process may be employed to bond adjacent layers without the use of a brazing alloy. While the multiple, stacked manifold laminar plates  88 ,  90 ,  92 ,  94 , and  96  are shown as independent plates bonded together, the stacked manifold laminar plates may be designed as a single strip so that each one of the stacked manifold laminar plates can be folded onto the next plate. Alternately, successive layers of the manifold laminar plates may be joined at their periphery by soldering, brazing or welding. Welding processes may include, but are not limited to, laser welding, electron-beam welding, ultrasonic welding, resistance welding, press welding, any of the processes referred to as “arc-welding,” GMAW, MIG, TIG or the like. 
         [0054]    The above laminar element bonding or welding processes assume that the heat exchanger element is comprised of metal or a metal alloy. The structure could however be comprised, without being limiting, of other materials such as ceramics, polymers, glasses or composites. Adhesives such as epoxies, cyanoacrylates, silicones or other materials may be employed to bond adjacent layers and/or seal the periphery of the heat exchanger element instead of or in addition to brazing and/or welding. 
         [0055]      FIG. 7  illustrates an alternative embodiment of the heat exchanging device with flow directors generally referred to as  200 . The heat exchanging device with flow directors  200  contains a main body  212 , preferably made of a laminar material and/or other materials that exchange heat including aluminum copper, nickel, brass or stainless steel, ceramics, plastics, glass, or other suitable materials which acts as a heat exchanging element. The main body  212  may be formed by an extrusion process, though other methods known to one of skill in the art may also be employed. The main body  212  is defined by a plurality of walls as described for the heat exchanging device with flow directors  10  and having a first end  222  and a second end  224 . 
         [0056]    The first end  222  of the main body  212  contains a substantially cylindrically shaped first manifold, an inlet manifold  226 , integrally formed or attached thereto. The manifold  226  contains a first open end  228  sized and shaped to allow fluids, such as a liquid or a gas, to enter therein, a second closed end  230 , and a manifold body  232  there between. The second end  224  of the main body  212  may be open to allow fluid that has entered into and flowed within the main body  212  to exit. The inlet manifold  226  is provided to facilitate coupling of fluid inlet lines, such as hoses, tubes or pipes, or other conduits to the heat exchanger. While the inlet manifold  226  is shown having a generally cylindrical shape, any shape may be used. 
         [0057]    Alternatively, the heat exchanging device with flow directors  200  contains a second manifold, an outlet manifold  234 , integrally formed or attached to the second end  224 . The outlet manifold  234  as shown contains a first end  236  which is open and sized and shaped to allow fluids, such as a liquid or a gas, to exit, a second end  238  which is closed, and an outlet manifold body  240 . While the outlet manifold  234  is shown having the first end  236  being open, it is within the scope of this invention that the second end  238 , or both ends  236  and  238  contain an opening for fluid flow. The outlet manifold  234  is provided to facilitate coupling of fluid outlet lines, such as hoses, tubes or pipes, or other conduits to the heat exchanger. While the outlet manifold  234  is shown having a generally cylindrical shape, any shape may be used. 
         [0058]    Referring to  FIG. 8A , the upper wall has been removed in order to illustrate the inner components and arrangement thereof. In addition, the outlet manifold  234  has been removed. The main body  212  is adapted to provide fluid containment, having a first proximal wall  242  and a second distal wall  244 . Both the first proximal wall  242  and the second distal wall  244  traverse the length of the heat exchanging device with flow directors  200  and have a height which extends from the inner surface  246  of bottom wall to the inner surface of top wall (not illustrated). The first proximal wall  242  and the second distal wall  244  function to contain and confine a heat exchanging fluid, such as a liquid or a gas, to the interior  248  of the heat exchanging device with flow directors  200 . 
         [0059]    Placed within the interior  248  are one or more heat exchanging elements, illustrated herein as heat exchanging fins  250 A- 250 D, collectively referred to as heat exchanging fins  250 . The fins  250  are preferably made of metal having heat conductive properties such as aluminum or copper. The fins are preferably formed during the aforementioned extrusion process. The fins  250  are arranged in a substantially parallel manner relative to each other and traverse the distance of the main body  212 , i.e. run from the first end  222  to the second end  224 , or may be discontinuous. Accordingly, the heat exchanging fin  250 A is aligned in a substantially parallel manner with the heat exchanger fin  250 B. Such arrangement provides for the formation of one or more fluid channels  252 . 
         [0060]    Each of the fins  250  has a length that traverses the length of the main body, running from the first end  222  to the second end  224 . The height of each fin extends from the inner surface  246  of the bottom wall to the inner surface of the top wall. The positioning of each of the fins  250 , as well as the physical characteristics, i.e. the height and length, provides individual channels for directional flow of fluid within the main body  212  of the heat exchanger  200 , and act as a thermally conductive path. Additionally, the fins  250  provide a thermally conductive path to the heat exchanger main body  212 . These elements promote controlled fluid flow and serve to prevent dead spots or undesirable circulating eddies. Alternatively, the fins  250  may be arranged in a discontinuous manner, having a fin which extends a predetermined distance, followed a predetermined distance with no fin structure. The alternating pattern of fin structure-no fin structure can be repeated along the length of the main body  212 . 
         [0061]    While providing flow distribution with the heat exchanger in this manner reduces the likelihood of excess and insufficient flow zones, one problem not addressed is the flow rate and/or flow distribution of fluids prior to reaching the channels  252 . To overcome such problems, the heat exchanger with flow directors  200  in accordance with the present invention utilizes one or more flow directors  254  integrally formed as part of fins  250  and extending into the inlet manifold  226 , the outlet manifold  234 , or combinations thereof. 
         [0062]    The embodiment of the heat exchanger with flow directors  200  illustrated in  FIG. 8A  shows flow directors  254  (individually as  254 A,  254 B,  254 C, and  254 D) preferably, but need not (i.e. can be free floating), contact the interior surface  258  by extending into the interior  260  of the inlet manifold  226 . The flow directors  254  assume a bent finger configuration. In this manner, directional flow of fluid entering into the heat exchanger with flow directors  200  can be directed to one or more of the fluid flow channels  252 . Referring to  FIG. 8B , fluid entering into the opening  228  of the inlet manifold  226  is directionally diverted into particular flow channels  252 . 
         [0063]    To achieve the directional diversion of fluid, the flow directors  254  are adapted and positioned to direct the fluid flow accordingly. As fluid flows into the inlet manifold  226 , see arrow  261  on  FIG. 8B , the fluid flow path  262  in the inlet manifold  226  is initially and predominantly in the direction of the longitudinal axis  264  of the inlet manifold  226 , see  FIG. 7 . At least one of the flow directors  254  is employed to urge the fluid from this path and into the main body  212 . 
         [0064]    As an illustrative example, the flow directors  254  have a terminal end  266  which extends into the inlet manifold  226 . The flow director  254  has a first surface  268  for contacting and diverting fluid into a channel  252  and a second surface  270  for contacting and diverting fluid flow along the longitudinal axis  264  of the inlet manifold  226 . As shown in  FIGS. 8A and 8B , each flow director  254 A- 254 D assumes a position which is offset and is in a parallel arrangement relative to the positioning of a flow director above or below. This arrangement allows each flow director  254 A- 254 D to be arranged in a step-like fashion along the interior  260  of inlet manifold  226 . Alternatively, the flow directors  254  can be arranged to have a more diagonal orientation. Preferably, the flow directors  254  have a curved surface  272  to provide gradual and efficient re-direction of the fluid flow direction so that flow entering the heat-exchanging element becomes aligned with the flow channels  252  thereby minimizing hydrodynamic pressure losses. 
         [0065]    The degree of curvature may vary depending on the type of fluid flow and other characteristics needed with respect to the exchange of heat per application. For example, the curvature may form an angle α that is between greater than 0 degrees and less than 180 degrees, and preferably around 90 degrees. Without these flow directors, the fluid in the fluid manifold  226  tends to continue in a straight path parallel to the longitudinal axis of the fluid manifold until the fluid reacts with the distal wall  244 . This reaction generates a great deal of turbulence, resulting in hydraulic inefficiency. Further, the fluid flow is now such that a disproportionate volume of fluid flows into the fluid channel nearest the distal wall  244 . This disproportionate flow results in uneven heat transfer and potential hot spots in the heat exchanger, and similarly the device to be cooled or heated. A further advantage of the application of the flow directors is in the reduction of mechanical wear on the heat exchanger and the fluid manifold. Such wear is aggravated by turbulent flow, cavitation and high-pressure fluid impact on the components of the system. The present design serves to minimize these negative effects. 
         [0066]    Referring to  FIGS. 9-11 , an illustrative example of formation of the bent finger like flow directors  254  is shown.  FIG. 9  illustrates the heat exchanger with flow directors  200  formed through an extrusion process. The inlet manifold  226  has not been attached, thereby exposing the first end  222 . Through the extrusion process, multiple channels  252  are formed, bounded by heat exchanging fins  250 . The flow directors  254  may be formed by removing, for example by sawing or milling after the extrusion process, a portion of the front, back and side walls that make up the heat exchanger main body  212 , as well as the first proximal wall  242  and the second distal wall  244 , see broken line  274  in  FIG. 9 , thereby exposing an overhang as part of the heat exchanging fins  250 , see  FIG. 11 . The overhang portion is then formed into the flow directors  254 . In the case of an extruded heat-exchanging element, the flow directors  254  may simply be extensions of the laminar flow elements, i.e. the heat exchanging fins  250  that are formed during the extrusion process. While the extrusion process is efficient and permits complex extrusion profiles to be formed through the use of an appropriate die, the process has its limitations. For example, the shape of an extruded part can essentially only be controlled in 2½ dimensions. That is, the part must have a constant shape profile throughout its length. And while the length can be specified, the profile along that length must remain constant. 
         [0067]    If the desired flow directors  254  are to be created from extensions of the extrusion profile, then their curved shape must be formed after the extrusion process. Bending these flow directors  254  may be accomplished either manually, with an automated bender or by application of a special tool. A convenient means of bending to form flow directors  254  is to employ an open topped tool with a plurality of substantially parallel curved channels. Forcing the flow directors  254  into the channels causes the flow directors  254  to bend to fit the curves. If plastically deformed, the flow directors  254  will remain curved and take on the shape desired for the flow directors. The open topped tool permits the heat exchanging element, and the now curved flow directors  254  to be lifted out of the tool. 
         [0068]    While the above embodiments have been described showing an inlet manifold  28 ,  228 , each embodiment may include an outlet manifold  34 ,  234  having the flow directors as having the same features and characteristics described herein. In addition, the outlet manifold  34  or  234  may contain flow directors arranged to direct outward fluid flow toward end  36  or  236  thereby providing for U-shaped fluid flow, or directed to end  238  to provide for Z-shaped fluid flow. 
         [0069]    All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference. 
         [0070]    It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and any drawings/figures included herein. 
         [0071]    One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims.

Technology Category: f