Patent Application
20210396481
The invention relates to a heat exchanger for coupling a first fluid to a second fluid so as to transfer heat and in a fluidically separate manner, comprising a fluid collector for receiving fluid, comprising a multiphase distributor for distributing fluid, comprising a first flow path for the first fluid, and comprising a plurality of multi-duct tubes, which are aligned parallel to one another and which each have a duct tube longitudinal axis. The respective multi-duct tubes lead into the multiphase distributor by forming a distributor orifice and into the fluid collector by forming a collector orifice. A second flow path for the second fluid thereby respectively extends through the multi-duct tubes, the fluid collector, and the multiphase distributor, wherein the multi-duct tubes extend through the first flow path for the first fluid, so that the first fluid can flow around and the second fluid can flow through the multi-duct tubes, respectively.
Heat exchangers of this type have been known for a long time and serve the purpose of exchanging or of transferring, respectively, thermal energy between a first fluid and a second fluid. They may be used, for example, in air conditioning systems or cooling units, preferably in large-capacity air conditioning systems or large-capacity cooling units.
In spite of large development efforts, the known heat exchangers have an icing problem in the area of the multi-duct tubes of the heat exchanger, which effect the heat exchange between the first and second fluid. It is generally possible to operate the heat exchangers for heating as part of a heating operation or for cooling as part of a cooling operation. During the heating operation, for example, thermal and flow-related condensate formation occurs at the multi-duct tubes, around which the first fluid flows, and at or in the area between the multi-duct tubes and the multiphase distributor. Condensate, for example water, originating from the first fluid deposits for example on the outside of the multi-duct tubes. The condensate flows downwards along the multi-duct tubes due to gravity, where it constricts or impedes the first flow path for the first fluid, so that, in terms of mass flow or volume flow, less first fluid can flow through the heat exchanger along the first flow path. The flow speed of the first fluid, for example, is reduced. As has been recognized, however, the reduction of the mass flow or of the volume flow or of the flow speed of the first fluid necessitates a decrease of the temperature in the area of the multi-duct tubes, wherein the condensate at the multi-duct tubes freezes gradually. This results in a continually increasing icing of the heat exchanger culminating in the total icing. The energy efficiency of the heat exchanger is diminished thereby, even though there is already the wish for more energy-efficient technical solutions for environmental reasons.
The basic idea of the invention lies in using the fluid collector and the multiphase distributor of a heat exchanger, compared to the previously known heat exchangers, basically in reversed installation positions.
For this purpose, it is provided that a heat exchanger for coupling a first fluid to a second fluid so as to transfer heat and in a fluidically separate manner, is equipped with at least one fluid collector, preferably with a hollow interior, for collecting, i.e. for receiving fluid, and with at least one multiphase distributor, preferably with a hollow interior, for distributing fluid, for example in a nozzle-like manner. It is possible that the fluid collector is suitable for distributing fluid, and the multiphase distributor for collecting fluid. In any event, the heat exchanger has or defines a first flow path for the first fluid, for example air or ambient air. The heat exchanger furthermore has a plurality of multi-duct tubes, which each have a duct tube longitudinal axis and which are aligned parallel or at an angle to one another, and which each lead into the multiphase distributor by forming a distributor orifice, and into the fluid collector by forming a collector orifice. The multi-duct tubes advantageously have a flow cross-section, which is constant throughout along the duct tube longitudinal axis, in order to allow a complete flow-through along the duct tube longitudinal axis. The multi-duct tubes are advantageously made of a material, which promotes a transfer of thermal energy from the first fluid to the second fluid, or vice versa, for example a heat-conductive plastic or a heat-conductive metallic material. As a whole, the multi-duct tubes, the fluid collector, and the multiphase distributor are fixed to one another. It is conceivable that the multi-duct tubes are soldered or welded to the multiphase distributor and to the fluid collector. A second flow path for a second fluid may furthermore lead through the multi-duct tubes, the fluid collector, and the multiphase distributor. The second fluid may be, for example, a coolant fluid, preferably water or glycol. The multi-duct tubes furthermore extend through the first flow path for the first fluid. This has the advantageous effect that the first fluid can flow around, for example in a perpendicular manner, and the second fluid can flow through the multi-duct tubes, for example in a hermetically sealed manner, respectively. This allows the function of a heat exchanger, namely the fluidically separate coupling of the first from the second fluid, and the transfer of thermal energy from the first fluid to the second fluid, or vice versa.
The fluid collector is arranged in the second flow path in such a way that, as part of a heating operation of the heat exchanger, in response to which heat is transferred from the second fluid to the first fluid, it is located downstream from the multiphase distributor. The second fluid can thus flow through the multiphase distributor, then through the multi-duct tubes, and then through the fluid collector. It is also safe to say that the fluid collector of the heat exchanger is arranged in the second flow path downstream, thus after the multiphase distributor. This has the effect that the first fluid absorbs thermal energy from the second fluid as part of the heating operation, so that the first fluid heats up. This furthermore has the effect that a pressure loss in the second fluid, which is caused, for example, by the constriction of the first flow path, may be slightly reduced in the heat exchanger, wherein a relatively large operating temperature range for the heat exchanger can be realized. The heat exchanger is thus advantageously able to operate for longer periods of time than previously, before an icing occurs. The energy efficiency can thus be improved.
As part of the heating operation of the heat exchanger, thermal energy can be transferred from the second fluid to the first fluid, experts thereby also refer to this as the “heating mode” or “heating operation” of the heat exchanger. The heating operation has the effect that the first fluid heats up. The heating operation of the heat exchanger may be realized by an “upward flow design” of the second fluid, wherein the first and second fluid basically flow from the bottom to the top through the heat exchanger, for example both opposite to the direction of gravity. “Upward flow design” may also mean that the first fluid and the second fluid flow parallel or virtually parallel to one another through the heat exchanger.
The heat exchanger preferred to be used in a heat exchanger system having at least two single heat exchangers, by way of example, each of them operating in a specific mode. By the nature of the heat exchanger system and depending on mode the single heat exchangers needs to work as either an evaporator or as a condenser, wherein a heating mode single heat exchangers is typically located outdoors and/or a cooling mode single heat exchangers is typically located indoors. For example, the indoor single heat exchanger is always working as the “opposite” single heat exchanger, e.g. when the outdoor single heat exchanger acts as an evaporator the indoor single heat exchanger works as a condenser. Thus the heat exchanger system is configured to selectively reject heat or to warm the space “indoor”.
Moreover, for example, the fluid collector and the multiphase distributor may be contained inside their respective manifolds. They are preferred not to be stand-alone devices, which could contain refrigerant without being in a manifold. So both devices can help to control the distribution or refrigerant path.
For example, fluid can flow hermetically sealed inside the first flow path and inside the second flow path, for example including within the “multi-duct tubes”, also called multi-port or multi-channel.
The fluid collector can also be arranged in the second flow path in such a way that, as part of a cooling operation of the heat exchanger, in response to which heat is transferred from the first fluid to the second fluid, it is located upstream of the multiphase distributor, so that the second fluid flows through the fluid collector, then through the multi-duct tubes, and then through the multiphase distributor.
As part of the cooling operation of the heat exchanger, thermal energy can be transferred from the first fluid to the second fluid, experts thereby also refer to this as the “cooling mode” or “cooling operation” of the heat exchanger. The cooling operation has the effect that the first fluid cools down. The cooling operation of the heat exchanger can advantageously be realized by a “downward flow design” of the second fluid, wherein the second fluid basically flows from the top to the bottom through the heat exchanger, thus in reverse to the “upward flow design”, for example in the direction of gravity. “Downward flow design” may also mean that the first fluid and the second fluid flow anti-parallel or virtually anti-parallel to one another through the heat exchanger.
It should thus be noted that, as a function of the selected operating state of the heat exchanger, the second fluid may flow through the heat exchanger in different directions along the second flow path, namely advantageously either from the bottom to the top, thus in opposite direction of the direction of gravity, or from the top to the bottom, thus in the direction of the direction of gravity.
The fluid collector may advantageously have a cylindrical base body with a hollow interior for guiding the second fluid, for example a square body or a tubular body. The tubular body may have a tubular-body longitudinal axis and at least two opening arrangements, which each penetrate the tubular body transversely to the tubular-body longitudinal axis, of individual openings, which are arranged spaced apart from one another along the tubular-body longitudinal axis. An opening arrangement can also be described as “phase”. The square body may also have a square-body longitudinal axis and at least two opening arrangements, which each penetrate the square body transversely to the square-body longitudinal axis, each opening arrangement formed of a plurality of individual openings, which are arranged spaced apart from one another along the square-body longitudinal axis. The second flow path for the second fluid may advantageously lead through the individual openings of the opening arrangements. The individual openings of the opening arrangements advantageously each form a nozzle, which basically place the second fluid into the multi-duct tubes in the manner of an evaporator. In the alternative, second fluid from the multi-duct tubes can flow into the fluid collector through the individual openings. A fluid collector equipped with the described opening arrangements provides the effect that the second fluid flowing through it can flow from the fluid collector into the multi-duct tubes or from the multi-duct tubes into the fluid collector particularly evenly and so as to be beneficial for flow. This has the advantage that, for example due to a reduction of the flow resistance, the energy efficiency of the heat exchanger is improved. The individual openings may be formed by individual bores.
With respect to the tubular-body longitudinal axis, the tubular body may furthermore advantageously have a tubular-body cross-section, which is constant throughout or which is variable along the tubular-body longitudinal axis. The tubular-body cross-section may be designed, for example, in a c-shaped or v-shaped manner.
The tubular body may advantageously have exactly two opening arrangements, thus two phases. The individual openings of a first opening arrangement may thereby be arranged spaced apart from one another along the tubular-body longitudinal axis by a first distance. The first distances can thereby be measured from center of the opening to center of the opening. A center of the opening may be formed or defined by the respective geometric center of an individual opening. The individual openings of a second opening arrangement may be arranged spaced apart from one another along the tubular-body longitudinal axis, each by forming a second distance. The second distances can thereby be measured from center of the opening to center of the opening. A center of the opening may also be formed or defined here by the respective geometric center of an individual opening. To be able to further improve the flow-through of the heat exchanger, the first distances of the individual openings of the first opening arrangement may be designed to be smaller than the second distances of the individual openings of the second opening arrangement. It is also conceivable that the first distances of the individual openings of the first opening arrangement are 54 mm (+/−5 mm) relative to one another, and that the second distances of the individual openings of the second opening arrangement are 108 mm (+/−10 mm) relative to one another. The individual openings of the first and second opening arrangement may thereby each have an opening diameter of 4.76 mm (+/−0.5 mm). In the alternative, the individual openings of the first opening arrangement may each have an opening diameter of 4.76 mm (+/−0.5 mm), and the individual openings of the second opening arrangement may have opening diameters, which are dimensioned with a size of 4.76 mm (+/−0.5 mm) and 6.35 mm (+/−0.6 mm), so as to alternate along the tubular-body longitudinal axis.
It may be provided that the individual openings of the first opening arrangement each have a first opening cross-section, and that the individual openings of the second opening arrangement each have a second opening cross-section. It may also be provided thereby that at least one or a plurality or all first opening cross-sections are smaller than the second opening cross-sections in terms of surface area. It is also conceivable that all first opening cross-sections are designed half as large as the second opening cross-sections in terms of surface area. This has the advantageous effect that the first opening arrangement, viewed in total, has a smaller opening cross-section, which is open to flow, than the second opening arrangement, in terms of surface area. For example, a larger fluid volume flow and/or fluid mass flow can thus flow through the second opening arrangement than through the first opening arrangement.
The duct tube longitudinal axes of the multi-duct tubes may furthermore each be aligned transversely or orthogonally with respect to the tubular-body longitudinal axis of the tubular body of the fluid collector. An angular or rectangular heat exchanger may thus be provided, which simplifies, for example, the assembly thereof.
It is further conceivable that the multiphase distributor has a cylindrical distributor tubular body with a hollow interior for guiding the second fluid or a distributor square body for guiding the second fluid. The distributor tubular body may define a distributor tubular-body longitudinal axis and may have at least one distributor opening arrangement, which penetrates the distributor tubular body transversely to the distributor tubular-body longitudinal axis, each opening arrangement formed of a plurality of distributor individual openings, which are arranged spaced apart from one another in the direction of the distributor tubular-body longitudinal axis. Each of the individual openings may expediently have an opening diameter of 1 mm. Fluid, for example the second fluid, can flow through the individual openings of the multiphase distributor, preferably from the multiphase distributor to the multi-duct tubes or, in the alternative, from the multi-duct tubes to the multiphase distributor.
The duct tube longitudinal axes of the multi-duct tubes may respectively be aligned transversely or orthogonally with respect to the distributor tubular-body longitudinal axis of the distributor tubular body of the multiphase distributor. An angular or rectangular heat exchanger may thus also be provided, which simplifies, for example, the assembly thereof.
The heat exchanger may have a fan, which is arranged in the first flow path, for driving the first fluid, for example air or ambient air, along the first flow path.
The heat exchanger may have a fluid pump, which is arranged in the second flow path, for driving the second fluid along the second flow path.
The multiphase distributor and the fluid collector or, in the alternative, the multiphase distributor or the fluid collector may advantageously be accommodated completely in a support tube. The support tube completely encloses the multiphase distributor and the fluid collector all around, so that fluid, for example the second fluid, can flow into or out of the respective support tube only through a support tube fluid connection of the respective support tube, so as to thus get to the multiphase distributor or to the fluid collector. The support tubes furthermore have passages for the multi-duct tubes, which are arranged at the multiphase distributor and fluid collector. The multi-duct tubes may be inserted, for example, through the passages of the support tubes and may lead into the multiphase distributor and the fluid collector. The multi-duct tubes may expediently be fixed by a material bond to the support tubes via soldering or welding.
The support tube fluid connections may be designed in such a way that a respective releasable supply hose can be arranged on them. This has the advantage that the heat exchanger can be fluidically connected to further components of a heat exchanger system, for example a fluid pump. The support tube fluid connections may either form a fluid inlet or a fluid outlet, depending on the flow direction of the second fluid along the second flow path.
It is furthermore conceivable to join two of the described heat exchangers to form a heat exchanger system. In addition to the two heat exchangers, the heat exchanger system may have a wedge-shaped housing, in which the two heat exchangers are arranged in a stationary manner and tilted at an angle to one another. It has been recognized that it is advantageous, when the heat exchangers are arranged in a v-shaped manner to one another. In any event, the heat exchanger system has at least one fan, which is arranged on the housing, for driving the first fluid, for example air or ambient air, and a fluid pump for driving the second fluid, so that the heat exchanger system can be operated for heating as part of a heating mode or for cooling as part of a cooling mode by the heat exchangers.
In summary, the invention may relate to a heat exchanger for coupling a first fluid to a second fluid so as to transfer heat. The heat exchanger may thereby have a fluid collector for receiving fluid, a multiphase distributor for distributing fluid, a first flow path for the first fluid, and a plurality of multi-duct tubes, which each have a duct tube longitudinal axis. The multi-duct tubes respectively lead into the multiphase distributor orifice and into the fluid collector by forming an orifice, wherein a second flow path for the second fluid extends respectively through the multi-duct tubes, the fluid collector, and the multiphase distributor. The multi-duct tubes thereby extend through the first flow path for the first fluid, so that the first fluid can flow around and the second fluid can flow through the multi-duct tubes, respectively. The multiphase distributor is arranged in the second flow path upstream of the fluid collector.
Further important features and advantages of the invention emerge from the dependent claims, from the drawings and from the associated description of the figures with reference to the drawings.
The features mentioned above and those which have yet to be explained below can be used not only in the respectively stated combination, but also in different combinations or on their own without departing from the scope of the present invention.
Preferred exemplary embodiments of the invention are illustrated in the drawings and are explained in more detail in the description below, wherein the same reference signs refer to identical or similar or functionally identical components.
In the following, preferred embodiments of the invention are described using the drawing.
In the drawings,
As a whole, the figures show a preferred exemplary embodiment of a heat exchanger, which is labeled with reference numeral 1, of which two pieces are integrated in an exemplary manner in a preferred exemplary embodiment of a v-shaped heat exchanger system 25, which is illustrated in
It is thus important to note that the second fluid can flow through the heat exchanger 1 in different directions along a second flow path 5 as a function of the selected operating state 22, 23 of the heat exchanger 1. To illustrate this, arrows, which are directed from the top to the bottom, and arrows, which are directed from the top to the bottom and from the bottom to the top, respectively labeled with reference numeral 5, are incorporated in
The heat exchanger system 25 furthermore has a fluid pump 28, which is indicated by a dashed box in
In a top view,
It can also be seen in
It can furthermore be seen in
It is additionally incorporated in
In
To be able to better see and describe the individual openings 13 of the two opening arrangements 12,
It can also be seen in
Lastly,
While the above description constitutes the preferred embodiments of the present invention, the invention is susceptible to modification, variation and change without departing from the proper scope and fair meaning of the accompanying claims.
