The present invention relates to droplet separators or demisters and, in particular, to droplet separators for being used in heat pumps and heat pumps which may be used to heat or cool buildings or else to heat or cool other objects.
The water vapor is fed via the suction line 12 to a compressor/condenser system 14 which comprises a flow machine, such as, for example, a centrifugal compressor, exemplarily in the form of a turbo compressor, which in
The flow machine is coupled to a condenser 18 which is configured to condense the compressed operating vapor. By means of condensing, the energy contained in the operating vapor is fed to the condenser 18 in order to be then fed to a heating system via the advance element 20a. The operating fluid flows back to the condenser via the return element 20b.
In accordance with the invention, it is advantageous to withdraw heat (energy) from the water vapor rich in energy by the cooler heating water directly, the heat (energy) being absorbed by the heating water such that same will heat up. An amount of energy is withdrawn from the vapor such that the same is condensed and also participates in the heating cycle.
This means that an introduction of material into the condenser or heating system takes place, which is regulated by an outlet 22 such that the condenser in its condensing space has a water level which, despite continuously feeding water vapor and, thus, condensate, will remain below a maximum level.
As has already been explained, it is advantageous to use an open cycle, i.e. evaporating water, which represents the source of heat, directly without a heat exchanger. Alternatively, the water to be evaporated could, however, also be heated up at first by an external heat source using a heat exchanger. However, it has to be kept in mind here that said heat exchanger also entails losses and apparatus complexity.
Additionally, it is advantageous, in order to avoid losses for the second heat exchanger, which up to now is necessarily present on the condenser side, to use the medium there directly, too, i.e. when taking the example of a house featuring underfloor heating, having the water coming from the evaporator circulate directly in the underfloor heating.
Alternatively, a heat exchanger may be arranged on the condenser side, which is fed by the advance element 20a and comprises the return element 20b, wherein said heat exchanger cools the water in the condenser and thus heats up a separate underfloor heating liquid which will typically be water.
Due to the fact that water is used as the operating medium, and due to the fact that only the evaporated part of the ground water is fed to the flow machine, the degree of purity of the water is not important. The flow machine is, as is the condenser and, perhaps, the directly coupled underfloor heating, supplied with distilled water such that, compared to present systems, the system entails reduced servicing. In other words, the system is self-cleaning since the system is supplied with distilled water only, which means that the water in the outlet 22 is not polluted.
Additionally, it is to be pointed out that flow machines exhibit the characteristic—similarly to a plane's turbine—of not bringing the compressed medium into contact with problematic substances, such as, for example, oil. Instead, the water vapor is compressed only by the turbine or the turbo compressor, but not brought into contact and, thus, polluted with oil or another medium affecting purity.
When there are no other restricting rules, the distilled water discharged by the outlet may then be easily fed again to the ground water. Alternatively, it may, for example, also be seeped in the garden or in an open area, or it may be fed to a water treatment plant via a channel, if rules call for this.
By the combination of water as an operating medium featuring a useful enthalpy difference ratio which is two times better compared to R134a and the consequently reduced requirements to the system being closed (rather, an open system is advantageous), and by using the flow machine, by means of which the compressing factors necessitated are achieved efficiently and without affecting purity, what is achieved is an efficient and environmentally neutral heat pump process which becomes even more efficient when the water vapor is condensed directly in the condenser, since not a single heat exchanger will be necessitated for the entire heat pump process.
In order to achieve a heat pump of high efficiency, it is important for all the components, i.e. the evaporator, the condenser and the compressor, to be designed to be favorable.
On the other hand, it is of great importance for the heat pump to exhibit high long-time stability, since, depending on the usage, it has to operate very long without any damage occurring or service being necessitated.
In particular when water is employed as an operating medium and when a flow machine, such as, for example, a turbo compressor or a centrifugal compressor, is used for compressing, relatively high revolution numbers of the compressor wheel are necessitated.
On the other hand, it is problematic that, when evaporating, the result is not only pure vapor, but vapor and additionally droplets of the operating liquid. However, when these droplets of the operating liquid impinge on the very quickly revolving radial wheel in the compressor, the radial wheel may be damaged, which may be avoided by reducing the evaporation efficiency in the evaporator, that is setting the parameters in the evaporation space such that the liquid to be evaporated in the evaporation space is not caused to move to strongly. However, this is of disadvantage in that the efficiency in the evaporator decreases and in that a larger volume is necessitated in order to achieve a sufficiently large amount of vapor for a heat pump performance necessitated.
Another solution is providing a droplet separator which ensures the vapor reaching the radial wheel not to contain any droplets or only a very limited number of droplets.
However, it is important with this droplet separator that the separator itself does not entail especially large losses. If the droplet separator represents a great resistance to the vapor, said resistance has to be compensated by an even higher revolution number of the compressor, which in turn is problematic with regard to efficiency and volume. It has been found out that droplet separators in the form of a mesh made of plastic threads are, with regard to manufacturing and setup, simple and cheap but, on the one hand, let drops pass which may result in problems in the radial wheel and, on the other hand, when being implemented such that they let pass only a very small number or no drops at all, represent a relatively high resistance to the vapor.
According to an embodiment, a droplet separator for separating droplets from a vapor-droplet mixture in motion may have: a plurality of curved fins made of a material; wherein each of the fins is curved in accordance with a radius of curvature, wherein the radius of curvature is between 1 cm and 10 cm, and wherein each fin of the plurality of fins forms a complete ring; and a holder for holding the curved fins at a distance to one another, wherein the fins and the holder are configured such that direct passage through the droplet separator is concealed such that drops, due to a flight path of the drops, in a vapor-droplet mixture do not pass the droplet separator but impinge on a fin, wherein the droplet separator includes a central region having a circular shape having a rotational symmetry around an axis, and wherein the fins are curved towards the axis of the central region of the droplet separator both at a top end and a bottom end of a respective fin.
According to another embodiment, an evaporator may have: an inventive droplet separator; a liquid feeder below the droplet separator; and a suction port above the droplet separator.
According to another embodiment, a method for manufacturing a droplet separator for separating drops from a vapor-droplet mixture in motion may have the steps of: providing a plurality of curved fins made of a material; wherein each of the fins is curved in accordance with a radius of curvature, wherein the radius of curvature is between 1 cm and 10 cm, and wherein each fin of the plurality of fins forms a complete ring; providing a holder for keeping the curved fins at a distance to one another; and implementing the fins and the holder such that direct passage through the droplet separator is concealed such that drops, due to a flight path of the drops, in the vapor-droplet mixture do not pass the droplet separator but impinge on a fin, wherein the droplet separator includes a central region having a circular shape having a rotational symmetry around an axis, and wherein the fins are curved towards the axis of the central region of the droplet separator both at a top end and a bottom end of a respective fin.
The present invention is based on the idea that droplet separation may be achieved efficiently and, at the same time, without significant losses by using a plurality of curved fins or vanes made of a typically rigid material which are held by a holder. In particular, the fins and the holders are configured such that direct passage through the droplet separator is concealed such that the drops, due to a flight path of drops, in the vapor-droplet mixture from which the droplet separator is to separate the drops, do not the pass the droplet separator, but impinge on a fin.
On the other hand, the vapor may pass the droplet separator, without causing any significant losses. This means that droplets are held back very sufficiently by the fact that same impinge on the fins and, from there, flow downwards and drop into the evaporator space, whereas the vapor may pass through the droplet separator. Droplet separation is ensured by the fact that there is no direct passage through the droplet separator, i.e., when holding the droplet separator against light, one cannot see through the droplet separator. Thus, a droplet which typically is on a straight flight path cannot pass the droplet separator.
Redirecting for vapor takes place such that the vapor is “taken up” by the curved fins in the evaporation space, i.e. where the transition from the liquid phase to the gaseous phase takes place, passed through the fins and output on the other side of the droplet separator at a direction which is adaptable optimally to the path which the vapor has to follow after the droplet separator. Typically, a suction port of a compressor will be arranged there, which is funnel-shaped and unites the vapor from a larger diameter to a smaller diameter. Advantageously, the curvature of the fins at the output of the droplet separator towards the suction port is configured such that the vapor is already introduced into the suction port optimally, i.e. into a central region thereof. This ensures that losses or turbulence do not occur, neither in front of the droplet separator nor behind the droplet separator, nor in front of nor at the suction port of the compressor, which would affect the efficiency of the heat pump. On the other hand, it is ensured that drops may be removed from the vapor efficiently such that, behind the droplet separator, there are no drops at all or only minimum amount of very small drops which, even when impinging on the compressor wheel, cannot cause any damage.
Embodiments of the present invention will be detailed subsequently referring to the appended drawings, in which:
However, vapor may easily pass in between the fins 201, 202, 203. In particular, the vapor is redirected gently in the lower region 202 due to the curvature of the fins, then passes along the curved wall of the respective fin, is redirected again, wherein, above the droplet separator 204, there is a relatively directed vapor flow directed to the center, as is symbolically illustrated in
In addition, a total number of eleven fins are arranged in
In the embodiments shown in
In one embodiment, the droplet separator, in top view, is of a round shape. Here, the fins are curved towards a central region of the droplet separator both at a top end, i.e. in the top part of
In the embodiments shown in the Figures, the plurality of fins form a full ring. This feature and the characteristic of the fins being curved result in the exiting vapor to be compressed towards the center and in the vapor at the same time, below the droplet separator where there are still rather chaotic vapor/droplet movements, to be taken and redirected relatively gently, whereas the drops, due to their rather straight flight paths, impinge on the fins and cannot penetrate the droplet separator.
Although in the embodiments shown in
In the embodiments shown in the Figures, each fin is formed as a sector of a surface of a sphere, the angle of the sector being determined by the height of the droplet separator.
In the embodiment shown in
Advantageously, a rigid plastic material is used which ensures that the droplet separator maintains its structural shape. Any plastic injection molding materials may be used here. The droplet separator in
Additionally, another passage 282 is provided by means of which overflow from the condenser may take place, if used at all. A corresponding symmetrical passage is illustrated at 283.
An exemplary evaporator comprising a droplet separator in accordance with
The vapor freed from drops is then compressed in the compressor, thereby increasing the temperature of the vapor considerably. The vapor present at the output of the compressor 409 in the condenser feed 415 is at a considerably increased temperature level compared to the input of the compressor in the line 410. The energy the vapor in the line 415 carries is than released in a condenser 416, said energy exemplarily being used for heating purposes directly or via a heat exchanger when operating the heat pump as a heating system. However, when operating the heat pump for cooling purposes, the evaporator outflow represents the cooling liquid and the condenser outflow, i.e. what is transported of the hot operating liquid to a heat sink, represents “waste heat”.
With regard to the droplet separator, the present invention is favorable in particular in connection with a suction port having a diameter of, for example, is 215 mm, as is illustrated in
In addition, it is obvious from
While this invention has been described in terms of several advantageous embodiments, there are alterations, permutations, and equivalents which fall within the scope of this invention. It should also be noted that there are many alternative ways of implementing the methods and compositions of the present invention. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and equivalents as fall within the true spirit and scope of the present invention.
Number | Date | Country | Kind |
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102012220186.6 | Nov 2012 | DE | national |
This application is a continuation of copending International Application No. PCT/EP2013/073005, filed Nov. 5, 2013, which is incorporated herein by reference in its entirety, and additionally claims priority from U.S. Patent Application No. 61/722,973, filed Nov. 6, 2012, and German Patent Application 102012220186.6, filed Nov. 6, 2012, which are all incorporated herein by reference in their entirety.
Number | Date | Country | |
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61722973 | Nov 2012 | US |
Number | Date | Country | |
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Parent | PCT/EP2013/073005 | Nov 2013 | US |
Child | 14703509 | US |