HEAT PUMP HAVING A FOREIGN GAS COLLECTION CHAMBER, METHOD FOR OPERATING A HEAT PUMP, AND METHOD FOR PRODUCING A HEAT PUMP
20180363960 ยท 2018-12-20
Inventors
Cpc classification
F25B43/043
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25B49/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25B2700/195
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25B30/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25B2339/047
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25B2700/21163
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25B2600/13
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F25B30/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25B43/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25B49/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A heat pump includes a condenser for condensing compressed working vapor; a foreign gas collection space arranged within the condenser, the foreign gas collection space comprising: a condensation surface which during operation of the heat pump is colder than a temperature of the working vapor to be condensed; and a partition wall arranged, within the condenser, between the condensation surface and a condensation zone; and a foreign gas discharge device coupled to the foreign gas collection space so as to discharge foreign gas from the foreign gas collection space.
Claims
1. Heat pump comprising: a condenser for condensing compressed working vapor, the condenser comprising a condensation zone; a foreign gas collection space arranged within the condenser, the foreign gas collection space comprising: a condensation surface which during operation of the heat pump is colder than a temperature of the working vapor to be condensed; and a partition wall arranged, within the condenser, between the condensation surface and the condensation zone; and a foreign gas discharge device coupled to the foreign gas collection space so as to discharge foreign gas from the foreign gas collection space.
2. Heat pump as claimed in claim 1, further comprising a compressor and an evaporator, wherein a channel for working vapor which leads from the evaporator to the compressor is arranged at least partly within the condenser and comprises a channel wall representing at least part of the condensation surface.
3. Heat pump as claimed in claim 1, wherein the condenser comprises a liquid feed inlet for directing liquid, which is to be heated by means of condensation, into the condenser, the liquid feed inlet comprising a wall which represents at least part of the condensation surface.
4. Heat pump as claimed in claim 1, wherein a channel for the working vapor is arranged within the condenser, wherein the partition wall surrounds and is spaced apart from the channel, and wherein the condensation zone is formed between the partition wall and a condenser housing.
5. Heat pump as claimed in claim 4, wherein the liquid feed inlet is configured to feed working liquid, which is to be heated by means of condensation, to the condenser from the top within a feed area during operation of the heat pump, and wherein the compressor is configured to feed compressed working vapor in a manner that is lateral in relation to the feed area during operation.
6. Heat pump as claimed in claim 1, wherein a liquid feed inlet leading into the condenser is configured to feed working liquid, which is to be heated by means of condensation, to the condensation zone, the liquid feed inlet being arranged such that between the partition wall and the condensation surface, less working liquid is fed to the foreign gas collection space than to the condensation zone, or such that no working liquid is fed to the foreign gas collection space.
7. Heat pump as claimed in claim 1, wherein the foreign gas collection space extends, within the condenser, from a bottom end to a top end, a foreign gas entrance of the foreign gas discharge device being arranged closer to the upper end than to the lower end or being arranged directly at the upper end of the foreign gas collection space.
8. Heat pump as claimed in claim 1, wherein the partition wall is arranged, in relation to the condensation surface, such that a steadied zone, within which a directed flow comprising water vapor and foreign gas enters, forms within the foreign gas collection space, so that due to condensation of the water vapor from the directed flow on the condensation surface, foreign gas accumulation may occur within the foreign gas collection space.
9. Heat pump as claimed in claim 1, wherein the condensation surface is at least partly made of metal.
10. Heat pump as claimed in claim 1, which further comprises an evaporator connected to a compressor via a vapor channel, the vapor channel extending from the bottom up, in the direction of operation, within a condenser housing, a wall of the vapor channel representing at least part of the condensation surface, the partition wall being spaced apart from and arranged around the wall of the vapor channel, and the condensation zone being laterally demarcated by the partition wall, so that the foreign gas collection space results which extends from the bottom up.
11. Heat pump as claimed in claim 10, wherein the condenser is configured and operated such that a liquid level forms at a base of the condenser during operation, wherein a lower end of the partition wall is arranged such that a gap results between the liquid level and the lower end, said gap being configured such that a directed flow of working vapor and foreign gas may enter into the foreign gas collection space through said gap.
12. Heat pump as claimed in claim 1, wherein the partition wall is arranged such that water vapor may better enter into the foreign gas collection space at a lower end than at an upper end thereof during operation of the heat pump, or such that no water vapor may enter into the foreign gas collection space at the upper end of the foreign gas collection space.
13. Heat pump as claimed in claim 1, wherein the partition wall is impenetrable to the working liquid to be heated and is configured to draw off a working liquid which is to be heated and is applied to the partition wall, and to form a steadied zone underneath the partition wall, said zone representing the foreign gas collection space, the condensation surface being arranged within the steadied zone.
14. Method of operating a heat pump comprising the following features: a condenser for condensing compressed working vapor; and a foreign gas collection space arranged within the condenser, and a condensation surface and a partition wall that is arranged between the condensation surface and a condensation zone, said method comprising: cooling the condensation surface so that the condensation surface be colder than a temperature of the working vapor to be condensed; and discharging foreign gas from the foreign gas collection space.
15. Method of producing a heat pump comprising the following features: a condenser for condensing compressed working vapor; and a foreign gas collection space arranged within the condenser, and a foreign gas discharge device which is coupled to the foreign gas collection space so as to discharge foreign gas from the foreign gas collection space, said method comprising: arranging, inside the condenser, a condensation surface, which during operation of the heat pump is colder than a temperature of the working vapor to be condensed; and arranging, inside the condenser, a partition wall between the condensation surface and a condensation zone.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] Embodiments of the present invention will be detailed subsequently referring to the appended drawings, in which:
[0038]
[0039]
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
[0047]
[0048]
[0049]
[0050]
[0051]
[0052]
DETAILED DESCRIPTION OF THE INVENTION
[0053]
[0054] This interleaved or intermeshing arrangement of the condenser and the evaporator, which arrangement is characterized in that the condenser base is connected to the evaporator base, provides a particularly high level of heat pump efficiency and therefore enables a particularly compact design of a heat pump. In terms of order of magnitude, dimensioning of the heat pump, e.g., in a cylindrical shape, is such that the condenser wall 114 represents a cylinder having a diameter of between 30 and 90 cm and a height of between 40 and 100 cm. However, the dimensioning can be selected as a function of the useful power class of the heat pump, but will advantageously range within the dimensions mentioned. Thus, a very compact design is achieved which additionally is easy to produce at low cost since the number of interfaces, in particular for the evaporator space subjected to almost a vacuum, can be readily reduced when the evaporator base in accordance with advantageous embodiments of the present invention is configured such that it includes all of the liquid feed inlets/discharge outlets and such that, as a result, no liquid feed inlets/discharge outlets from the side or from the top are required.
[0055] In addition, it shall be noted that the operating direction of the heat pump is as shown in
[0056] This arrangement, which is mutually interleaved in that the evaporator is almost entirely or even entirely arranged within the condenser, enables very efficient implementation of the heat pump with optimum space utilization. Since the condenser space extends right up to the evaporator base, the condenser space is configured within the entire height of the heat pump or at least within a major portion of the heat pump. At the same time, however, the evaporator space is as large as possible since it also extends almost over the entire height of the heat pump. Due to the mutually interleaved arrangement in contrast to an arrangement where the evaporator is arranged below the condenser, the space is exploited in an optimum manner. This enables particularly efficient operation of the heat pump, on the one hand, and a particularly space-saving and compact design, on the other hand, since both the evaporator and the condenser extend over the entire height. Thus, admittedly, the levels of thickness of the evaporator space and of the condenser space decrease. However, one has found that the reduction of the thickness of the evaporator space, which tapers within the condenser, is unproblematic since the major part of the evaporation takes place in the lower region, where the evaporator space fills up almost the entire volume available. On the other hand, the reduction of the thickness of the condenser space is uncritical particularly in the lower region, i.e., where the evaporator space fills up almost the entire region available since the major part of the condensation takes place at the top, i.e., where the evaporator space is already relatively thin and thus leaves sufficient space for the condenser space. The mutually interleaved arrangement is thus ideal in that each functional space is provided with the large volume where said functional space involves said large volume. The evaporator space has the large volume at the bottom, whereas the condenser space has the large volume at the top. Nevertheless, that corresponding small volume which for the respective functional space remains where the other functional space has the large volume contributes to an increase in efficiency as compared to a heat pump where the two functional elements are arranged one above the other, as is the case, e.g., in WO 2014072239 A1.
[0057] In advantageous embodiments, the compressor is arranged on the upper side of the condenser space such that the compressed vapor is redirected by the compressor, on the one hand, and is simultaneously fed into a marginal gap of the condenser space. Thus, condensation with a particularly high level of efficiency is achieved since a cross-flow direction of the vapor in relation to a condensation liquid flowing downward is achieved. This condensation comprising cross-flow is effective particularly in the upper region, where the evaporator space is large, and does not require a particularly large region in the lower region where the condenser space is small to the benefit of the evaporator space, in order to nevertheless allow condensation of vapor particles that have reached said region.
[0058] An evaporator base connected to the condenser base is advantageously configured such that it accommodates within it the condenser intake and drain, and the evaporator intake and drain, it being possible, additionally, for certain passages for sensors to be present within the evaporator and/or within the condenser. In this manner, one achieves that no passages of conduits through the evaporator are required for the capacitor intake and drain, which is almost under a vacuum. As a result, the entire heat pump becomes less prone to defects since each passage through the evaporator would present a possibility of a leak. To this end, the condenser base is provided with a respective recess in those positions where the condenser intakes and drains are located, to the effect that no condenser feed inlets/discharge outlets extend within the evaporator space defined by the condenser base.
[0059] The condenser space is bounded by a condenser wall, which can also be mounted on the evaporator base. Thus, the evaporator base has an interface both for the condenser wall and for the condenser base and additionally has all of the liquid feed inlets both for the evaporator and for the condenser.
[0060] In specific implementations, the evaporator base is configured to comprise connection pipes for the individual feed inlets, which have cross-sections differing from a cross-section of the opening on the other side of the evaporator base. The shape of the individual connection pipes is then configured such that the shape, or cross-sectional shape, changes across the length of the connection pipe, but the pipe diameter, which plays a part in the flow rate, is almost identical with a tolerance of 10%. In this manner, water flowing through the connection pipe is prevented from starting to cavitate. Thus, on account of the good flow conditions obtained by the shaping of the connection pipes, it is ensured that the corresponding pipes/lines can be made to be as short as possible, which in turn contributes to a compact design of the entire heat pump.
[0061] In a specific implementation of the evaporator base, the condenser intake is split up into a two-part or multi-part stream, almost in the shape of eyeglasses. Thus, it is possible to feed in the condenser liquid in the condenser at its upper portion at two or more locations at the same time. Thus, a strong and, at the same time, particularly even condenser flow from top to bottom is achieved which enables achieving highly efficient condensation of the vapor which is introduced into the condenser from the top as well.
[0062] A further feed inlet, having smaller dimensions, within the evaporator base for condenser water may also be provided in order to connect a hose therewith which feeds cooling liquid to the compressor motor of the heat pump; what is used to achieve cooling is not the cold liquid which is supplied to the evaporator but the warmer liquid which is supplied to the condenser but which in typical operational situations is still cool enough for cooling the motor of the heat pump.
[0063] The evaporator base is characterized in that it exhibits combined functionality. On the one hand, it is ensures that no condenser feed inlets need to be passed through the evaporator, which is under very low pressure. On the other hand, it represents an interface toward the outside, which advantageously has a circular shape since in the case of a circular shape, a maximum amount of evaporator surface area remains. All of the feed inlets/discharge outlets lead through the one evaporator base and from there extend either into the evaporator space or into the condenser space. It is particularly advantageous to manufacture the evaporator base from plastics injection molding since the advantageous, relatively complicated shapes of the intake/drain pipes can be readily implemented in plastics injection molding at low cost. On the other hand, it is readily possible, due to the implementation of the evaporator base as an easily accessible workpiece, to manufacture the evaporator base with sufficient structural stability so that it can readily withstand in particular the low evaporator pressure.
[0064] In the present application, identical reference numerals relate to elements which are identical or identical in function; however, not all of the reference numerals will be repeated in all of the drawings if they come up more than once.
[0065]
[0066] In particular, the heat pump generally includes an evaporator 300 coupled to a compressor 302 so as to suck in, compress and, thus, heat up cold working vapor via a vapor pipe 304. The heated-up and compressed working vapor is discharged to a condenser 306. The evaporator 300 is coupled to a region to be cooled 308, specifically via an evaporator intake line 310 and an evaporator drain line 312, which typically has a pump 314 provided therein. In addition, a region to be heated 318 is provided which is coupled to the condenser 306, specifically via a condenser intake line 320 and a condenser drain line 322. The condenser 306 is configured to condense heated-up working vapor within the condenser intake channel 305.
[0067] In addition, provision is made of a gas trap which is coupled to the condenser 306 via a foreign gas feed inlet 325. The gas trap includes, in particular, a housing 330 comprising a foreign gas feed entrance 332 and possibly further foreign gas feed entrances 334, 336. Moreover, the housing 330 includes a working liquid feed inlet 338 as well as a working liquid discharge outlet 340. The heat pump further includes a pump 342 for pumping off gas from the housing 330. In particular, the working liquid feed inlet 338, the working liquid discharge outlet 340 and the housing are configured and arranged such that during operation, a flow of working liquid 344 takes place from the working liquid feed inlet 338 to the working liquid discharge outlet 340 within the housing 330.
[0068] In addition, the working liquid feed inlet 338 is coupled to the heat pump such that during operation, the heat pump has working liquid fed to it which is colder than working vapor within the condenser that is to be condensed and which is advantageously even colder than the working liquid which enters into the condenser or exits from the condenser. For this purpose, working liquid is advantageously taken from the evaporator drain line at a branch-off point 350 since said working liquid is the coldest working liquid within the system. The branch-off point 350 is located (in the direction of flux) downstream from the pump 314, so that the gas trap requires no pump of its own. In addition, it is advantageous to couple the backflow from the gas trap, i.e. the working liquid discharge outlet 340, to a branching point 352 of the drain line that is arranged upstream from the pump 314.
[0069] Depending on the implementation, the flow of working liquid through the gas trap, i.e. the stream of working liquid, represents a volume that is smaller than 1% of the main flow accomplished by the pump 314, and advantageously even lies within the order of magnitude of 0.5 to 2 of the main flow, which flows from the evaporator into the region to be cooled 308, or into a heat exchanger to which the region to be cooled may be connected, via the evaporator outlet 312.
[0070] Even though
[0071] As is shown in
[0072] Due to the pressure differences between the pressure prevailing within the condenser 306 and the pressure prevailing within the gas trap, which gas trap has, due to the low temperature of the working liquid, a pressure of the order of magnitude of that of the evaporator, a flow automatically occurs from the condenser 306 into the housing 330 of the gas trap through the foreign gas feed inlet 325. The water vapor which is contained within the mixture of foreign gas and water vapor and which enters into the housing at the foreign gas feed inlet 332, 334, 336 tends to flow toward the coldest place. The coldest place is where the working liquid enters into the housing, i.e. at the working liquid entrance, or working liquid feed inlet, 338. Thus, water vapor flows from the bottom up within the housing 330. Said flow of water vapor carries along the foreign gas atoms which will then, as indicated at 357, accumulate within the gas trap at the top because they cannot condense along with the working liquid. Therefore, the gas trap results in that an automatic, as it were, flow from the condenser into the housing takes place without requiring a pump for this purpose, and in that the foreign gas will then flow from the bottom up within the gas trap and will accumulate in the upper area of the housing 330 and will be able to be pumped off from there by the pump 342.
[0073] As shown in
[0074] As shown in
[0075] The pump 342 is controlled via a controller 373. Controlling of the pump may take place on the grounds of a pressure difference or of an absolute pressure, on the grounds of a temperature difference or an absolute temperature, or on the grounds of an absolute time control or of a time-interval control. Possible control is effected, for example, via a pressure P.sub.trap 374 prevailing within the gas trap. Alternative control takes place via the inflow temperature T.sub.in 375 at the working liquid feed inlet 338 or via an outflow temperature T.sub.out 376. In particular, the outflow temperature T.sub.out 376 at the working liquid discharge outlet 340 is a measure of how much water vapor has condensed from the foreign gas feed inlet 325 into the working liquid. At the same time, the pressure prevailing within the gas trap P.sub.trap 374 is a measure of how much foreign gas has already accumulated. As the amount of foreign gas accumulated increases, the pressure within the housing 330 increases, and once a specific pressure is exceeded, the controller 373 may be activated, for example, to switch on the pump 342, specifically for such time until the pressure has returned to the desired low range. After that the pump may be switched off again.
[0076] An alternative control parameter for the pump is, e.g., the difference between T.sub.in 375 and T.sub.out 376. For example, if it turns out that the difference between said two values is smaller than a minimum difference, this will mean that hardly any water vapor condenses anymore due to the increased pressure prevailing within the gas trap. Therefore it is useful to switch on the pump 342, specifically for such time until a difference exceeding a specific threshold value is reached. After that, the pump is switched off again.
[0077] Therefore, possible quantities to be measured are the pressure, the temperature, e.g. at the point of condensation, a temperature difference between the water feed inlet and the point of condensation, a driving pressure increase for the entire condensation process, etc. As depicted however, the simplest possibility is to perform control via a temperature difference or a time interval, for which no sensors are required at all. This is readily possible in the present embodiment since the gas trap provides very efficient foreign gas accumulation and since, consequently, there are no problems regarding too high an extraction of working vapor from the system when the pump is not operated without interruption.
[0078]
[0079] Therefore,
[0080]
[0081]
[0082] To improve condensation it is useful, in particular in the embodiment shown in
[0083] Therefore, while
[0084] Advantageously, the housing 330 is configured to be elongated, specifically as a pipe having a diameter of 50 mm or more at the top within the foreign gas accumulation space 328 and having a diameter of 25 mm or more at the bottom, i.e. within the condensation area. In addition, it is advantageous for the condensation area and/or flow area, i.e. the difference between the intake 338 and the drain 340 with regard to the perpendicular height to have a length of at least 20 cm. Moreover, it is advantageous for a flow to take place, i.e. for the gas trap to have at least a perpendicular component, even though it may be arranged in an oblique manner. However, a completely horizontal gas trap is not advantageous but is possible as long as during operation, working liquid flows, within the housing, from the working liquid feed inlet to the working liquid discharge outlet.
[0085]
[0086] In addition, the intake 310 leading into the system 300 and the drain 312 leading out of the system 300 are also coupled to a heat exchanger 398, which in turn may typically be couplable, on the customer's side, to an area to be cooled 308. In the example of a cooling application for the heat pump, the area to be cooled is a room to be cooled, such as a computer room, a process room, etc. In the example of a heating application for the heat pump, the area to be cooled would be, e.g., an environmental area, e.g., air in case of an air heat pump, ground in case of a heat pump with geothermal collectors, or a ground water/sea water/brine area from which heat is to be extracted for heating purposes.
[0087] Coupling between the two heat pump stages may take place as a function of the implementation. If coupling takes place such that one stage is a cold stage or a cold can, as it were, the second stage will be the warm stage or warm can, as it were. Said designations stem from the fact that the temperatures prevailing within the respective elements are colder in the first stage than in the second stage when both stages are in operation.
[0088] What is particularly advantageous about the present invention is the fact that the condensers of the second stage and of any further stages that may be present may all be connected to one and the same gas trap, or to one and the same gas trap housing 330. For example,
[0089] In addition, it shall be noted that the branching off of working liquid into the gas trap takes place in an amount of smaller than or equal to 1% of the main flow, i.e. of the entire flow from the evaporator 300 to the heat exchanger 398 and is advantageously even smaller than or equal to 1.
[0090] The same applies to the branching off of vapor from the condenser via the feed line 325 or 525. Here, the cross section of the line leading from the condenser into the housing 330 is typically configured such that at least 1% of the main gas flow is branched off into the condenser, or advantageously even less than or equal to 1 of the gas flow is branched off into the condenser. However, since the entire closed-loop control takes place automatically on the basis of the pressure difference from the respective condenser into the gas trap, precise dimensioning here is not critical to proper functioning here.
[0091]
[0092] Moreover, a grid 209 is arranged which is configured to support fillers not shown in
[0093] The condenser of
[0094] In addition, a vapor feeder is also provided which, as shown in
[0095] What is not shown in
[0096] Please refer to
[0097]
[0098]
[0099] In addition, the condenser advantageously has condenser liquid distribution means comprising two or more feeding points. A first feeding point is therefore connected to a first portion of a condenser intake. A second feeding point is connected to a second portion of the condenser intake. Should there be more feeding points for the condenser liquid distribution means, the condenser intake will be split up into further portions. The upper region of the heat pump of
[0100] What will be described below with reference to
[0101] Alternatively, the foreign gas discharge device 906 is configured as a gas trap, comprising the housing and the feed inlets/discharge outlets as were described with regard to
[0102] However, on the grounds of optimum foreign gas accumulation and the simplifications associated therewith in terms of refilling and disposal of drawn-off working vapor, it is advantageous to select the two-stage variant, i.e. the combination of aspect 1 and aspect 2 of the present invention.
[0103]
[0104] On the side facing the condenser, the partition wall 901a has a temperature below the saturated-vapor temperature prevailing within the condenser. In addition, on the side facing the evaporator, the partition wall 901a has a temperature above the saturated-vapor temperature prevailing there. Thus, it is ensured that the suction mouth, or vapor channel, is dry and that no water drops are present within the vapor, in particular when the compressor motor is activated. Thus, the impeller wheel is prevented from being damaged by drops present within the vapor.
[0105] In particular, the water vapor feed inlet allows water vapor 112 to flow in continuously, the orders of magnitude of water vapor flowing in typically being at least 1 liter per second. The pressure of the water vapor is equal to or higher than the resulting saturated-vapor pressure of the condenser water fed in through the water feed inlet 402, which condenser water is also designated by 1002 in
[0106] A representation of functionality is shown in
[0107] If condensation stops, the proportion of foreign gas and, therefore, the partial pressure, will be higher. Then, or as early as condensation decreases, the foreign gas discharge device may discharge foreign gas, for example by means of a connected vacuum pump which performs suction from the steadied zone, i.e. from the foreign gas collection space.
[0108] Said suction may be performed in a closed-loop controlled manner, in a continuous manner or in an open-loop controlled manner. Possible quantities to be measured are the pressure, the temperature at the point of condensation, a temperature difference between the water feed and the point of condensation, a driving pressure increase for the entire condensation process toward the water exit temperature, etc. All of said quantities may be used for closed-loop control. Open-loop control, however, may also be performed simply by means of a time interval controller which switches on the vacuum pump for a specific time period and then switches it off again.
[0109]
[0110] Advantageously, the partition wall 902 is sealed toward the top in the embodiments depicted in
[0111] As is further shown in
[0112] While this invention has been described in terms of several 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.