Background technology
Common refrigerator comprises compressor, evaporimeter, condenser and safety valve, and circulating refrigerant is to be delivered to condenser from evaporimeter by heat exchange with heat.
As 1 is the schematic diagram that common refrigerator 10 is shown.
As shown in Figure 1, refrigerator 10 comprises evaporimeter 30, condenser 20 and compressor 40.Cold water 31 evaporimeter 30 of flowing through, cooling water 21 condenser 20 of flowing through.
Cold-producing medium 51,52 circulates in compressor 40, and compressor 40 makes evaporimeter 30 be connected to condenser 20.The cold-producing medium 51 of process evaporimeter 30 flows into compressors 40 by the inlet portion 47 of compressor 40, and is flowed out from the export department 48 of compressor 40 by both stage impellers 41 and 42 refrigerant compressed 52, flows into condenser 20 then.
As shown in Figure 1, in compressor 40, both stage impellers 41 and 42 is arranged on the axle 43, and impeller 41 and 42 since axle 43 rotated by motor 45 and rotation thereupon.Here, gear 44 and 46 is set motor 45 is connected to axle 43, so that transmit moment of torsion.Though not shown in the figures, can connect thrust bearing between gear 44 and the axle 43.
In common compressor 40, concentrate on a direction because be delivered to the thrust of gear 46 and 44, increase so be applied to the load of above-mentioned bearing, and the load that therefore is applied to motor 45 also increases.Increase because be applied to the load of motor 45, so the outlet temperature of cold water raises, this causes the temperature difference of compressor to increase.Therefore, the efficient of compressor reduces.
For temperature difference that reduces compressor and the efficient that improves refrigerator, comprised " two turbine centrifugal chilling unit " of interconnected two refrigerators in use.The agent of two turbine centrifugal refrigerating is the increase capacity by the refrigerating efficiency that improves refrigerator self.In two turbine centrifugal chilling units, be provided with two compressors.Yet in existing pair of turbine centrifugal chilling unit, the temperature difference of a compressor is than the temperature difference height of another compressor in two compressors.Therefore, have to design independently and make this two compressors.Just additionally need be used to drive the driver element of the impeller of each compressor, and the overall dimensions of refrigerator increases.Therefore, as mentioned above, the problem that exists compressor efficiency to reduce.
Summary of the invention
The invention provides a kind of pair of turbine centrifugal chilling unit, comprising two compressors, two evaporimeters and two condensers to reduce the temperature difference of compressor, compressor is configured to identical temperature difference operation, and the impeller of compressor is by single drive unit drives, realizes thus that size reduces and efficient improves.
In a scheme, a kind of pair of turbine centrifugal chilling unit is provided, comprising: first evaporimeter of serial or parallel connection and second evaporimeter; First condenser of serial or parallel connection and second condenser; And first compressor and second compressor that comprise impeller, wherein cold water through first evaporimeter after through second evaporimeter, and cooling water through first condenser after through second condenser, first compressor that comprises cold-producing medium is connected to second evaporimeter with first condenser, and second compressor that comprises cold-producing medium is connected to first evaporimeter with second condenser, and the impeller of first compressor and second compressor is rotated synchronously with single driver element.
In addition, the impeller of first compressor and second compressor can be connected by single rotating shaft, and the impeller of first compressor and second compressor can be owing to rotating rotating shaft with driver element and being rotated synchronously.
In addition, driver element can be connected to the central authorities of rotating shaft, and the impeller of first compressor and second compressor can be relative about the central portion between them of rotating shaft.
In addition, the inlet portion of first compressor and second compressor can be respectively equipped with inlet guide vane (IGV).
In addition, first compressor and second compressor can have the capacity that differs from one another.
Make the temperature difference of each compressor reduce because comprise above-mentioned pair of turbine centrifugal chilling unit of two evaporimeters, two compressors and two condensers, so can realize the optimum performance of compressor.
In addition, synchronously driven because the impeller of two compressors is come with single driver element, so can realize having small size and high efficiency compressor.
The specific embodiment
Referring now to the accompanying drawing that exemplary embodiment is shown, exemplary embodiment is described more completely hereinafter.Yet the present invention can many different forms implement, and should not be construed as the exemplary embodiment that is confined to propose here.Not equal to, provide these exemplary embodiments in order that make the present invention thorough to those skilled in the art and complete, and give full expression to scope of the present invention.In this manual, the details of well-known features and technology can be omitted, in order to avoid unnecessarily obscure illustrated embodiment.
Unless otherwise defined, all terms used herein (comprising scientific and technical terminology) have the identical meaning with those of ordinary skills' common sense.Will be further understood that, term as those terms that define in normally used dictionary, should be interpreted as having and they consistent meanings in correlation technique and linguistic context of the present invention, unless define clearly in this specification, should not explain with the idealized or excessive formal meaning.
In the accompanying drawings, identical Reference numeral is represented components identical.Shape in the accompanying drawing, size and regional or the like may be for the sake of clarity and to some extent exaggerative.
Fig. 2 is the schematic diagram that illustrates according to a kind of pair of turbine centrifugal chilling unit 101 of embodiment.
As shown in Figure 2, according to embodiment, first evaporimeter 121 and second evaporimeter 122 are connected in series.Cold water 123 flows into an end of first evaporimeter 121 that is connected in series, and through first evaporimeter 121, again through second evaporimeter 122, flows out then.
First condenser 111 and second condenser 112 are connected in series.Cooling water 113 flows into second condenser 112 through first condenser 111, again through second condenser 112, flows out then.
First compressor 131 is connected to first condenser 111 and second evaporimeter 122, thus so that the circulation of the cold-producing medium of first compressor 131 and the cooling water 113 of first condenser 111 and cold water 123 heat-shifts of second evaporimeter 122.Second compressor 132 is connected to second condenser 112 and first evaporimeter 121, thus so that the circulation of the cold-producing medium of second compressor 132 and the cooling water 113 of second condenser 112 and cold water 123 heat-shifts of first evaporimeter 121.
The temperature that flows into the cold water of first evaporimeter 121 is 12 ℃, and the temperature of the cold water that flows out from second evaporimeter 122 is 7 ℃, and the temperature that flows into the cooling water of first condenser 111 is 32 ℃, and the temperature of the cooling water that flows out from second condenser 112 is 37 ℃.
That does not consider evaporimeter and condenser leaves temperature difference (LTD), and the temperature difference of first compressor 131 is 27.5 ℃ (34.5 ℃-7 ℃), and the temperature difference of second compressor 132 also is 27.5 ℃ (37 ℃-9.5 ℃).
In the two turbine centrifugal chilling units 101 according to embodiment, as mentioned above, two compressors 131 and 132 temperature difference are equal to each other.Therefore, as described below, can easily realize using single driver element to come the design of the impeller of two compressors of driven in synchronism.
Hereinafter, will describe according to two compressors 131 of embodiment and 132 configuration with reference to figure 2.
According to embodiment, first compressor 131 is the two-stage compression system with two impellers 145 and 146.Cold-producing medium 151 flows out from second evaporimeter 122, and the inlet portion 141 by first compressor 131 enters first compressor 131, and cold-producing medium is through impeller 145 be compressed in 146 o'clock.Cold-producing medium 152 after being compressed flows out from first compressor 131 by export department 142, and flows into first condenser 111.
Second compressor 132 is the two-stage compression system with two impellers 143 and 144.The cold-producing medium 153 that flows out from first evaporimeter 121 flows into second compressor 132 by the inlet portion 143 of second compressor 132, and this cold-producing medium is through impeller 143 be compressed in 144 o'clock.Cold-producing medium 154 after being compressed flows out from second compressor 132 by export department 144, and flows into second condenser 112.
According to embodiment, the impeller 143,144,145,146 that single driver element 163 rotates two compressors 131,132 is set.In this embodiment, use motor as driver element 163.
The impeller 143,144,145,146 of two compressors 131,132 is connected by rotating shaft 161.Gear 162 is arranged on the central portion of rotating shaft 161, and the impeller 145,146 of first compressor 131 is relative about the central portion between them of rotating shaft 161 with the impeller 143,144 of second compressor 132.One end of driver element 163 is connected to a gear, and is connected to gear 162 engagements of this gear and the rotating shaft 161 of driver element 163.In this configuration, single driver element 163 rotation rotating shafts 161, and along with rotating shaft 161 rotations, two compressors 131 and 132 the i.e. rotation synchronously of impeller 143,144,145,146.
According to embodiment, because drive two independently compressors 131,132, so reduced the cumulative volume of compressor assembly by single driver element 163.Therefore, the overall dimensions of two turbine centrifugal chilling units 101 reduces.
In addition, because the impeller of two compressors is symmetrically arranged, appears at rightabout and cancel each other out so be applied to the thrust of two end faces of gear 162.Therefore, the load that is applied to the bearing (not shown) that is used for gear 162 reduces, and this load that causes being applied to driver element 163 reduces, and has improved the efficient of driver element 163.The efficient of driver element 163 improves the outlet temperature that causes cooling water and reduces, and this temperature difference that causes compressor 131 and 132 reduces.Therefore, the efficient with reduced overall system improves and the advantage of the efficient raising of whole refrigerator.In addition, in design during bearing, can realize the design of bearing and need not to pay close attention to the thrust that is applied to specific direction.
According to embodiment, for ease of adjusting load, the inlet portion of first compressor 131 and second compressor 132 is provided with the inlet guide vane (IGV) that is used to adjust the load that is applied.
According to embodiment,, can obtain the various combinations of capacity with compressor and heat exchanger (condenser and evaporimeter) because first compressor 131 and second compressor 131 are separated from each other.For example, compressor 131 and 132 capacity can be set at 1 respectively, 000RT and 500RT.The size of heat exchanger is determined according to the capacity of compressor.Even in this case, the impeller of compressor also is to be arranged on symmetrically on the single rotating shaft, and because impeller is symmetrically arranged, so even under the situation that the capacity of two compressors differs from one another, also demonstrate the effect that the thrust of bearing is offset.
In this embodiment, two evaporimeters 121 and 122 are connected in series, and two condensers 111 and 112 are connected in series, yet embodiment is not limited to such configuration.Hereinafter, will another embodiment be described with reference to figure 3.
Fig. 3 is the schematic diagram that illustrates according to a kind of pair of turbine centrifugal chilling unit 201 of another embodiment.
As shown in Figure 3, in the two turbine centrifugal chilling units 201 according to present embodiment, first evaporimeter 221 and second evaporimeter 222 are connected in parallel.Cold water 223 flows into from an end of first evaporimeter 221 that is connected in parallel, flows out from the other end of first evaporimeter 221, and the end from second evaporimeter 222 flows into again, through second evaporimeter 222, and flows out from the other end of second evaporimeter 222.
First condenser 211 and second condenser 212 are connected in parallel.Cooling water 213 flows into from an end of first condenser 211 that is connected in parallel, flows out from the other end of first condenser 211, and the end from second condenser 212 flows into again, through second condenser 212, and flows out from the other end of second condenser 212.
First compressor 231 is connected to first condenser 211 and second evaporimeter 222, thus and the circulation of the cold-producing medium of first compressor 231 and the cooling water of first condenser 211 and the cold water heat-shift of second evaporimeter 222.Second compressor 232 is connected to second condenser 212 and first evaporimeter 221, thus and the circulation of the cold-producing medium of second compressor 232 and the cooling water of second condenser 212 and the cold water heat-shift of first evaporimeter 221.
Here, the temperature that flows into the cold water of first evaporimeter 221 is 12 ℃, and the temperature of the cold water that flows out from second evaporimeter 222 is 7 ℃, and the temperature that flows into the cooling water of first condenser 211 is 32 ℃, and the temperature of the cooling water that flows out from second condenser 212 is 37 ℃.
Do not consider the LTD of evaporimeter and condenser, the temperature difference of first compressor 231 is 27.5 ℃ (34.5 ℃-7 ℃), and the temperature difference of second compressor 232 also is 27.5 ℃ (37 ℃-9.5 ℃).Just, the temperature difference of two compressors is equal to each other.
Because according to this embodiment, the impeller 245,246,247,248 of compressor 231,232, rotating shaft 161, gear 262 and be arranged on annexation between the driver element 263 in two turbine centrifugal chilling units 201, and cold-producing medium 251,252,253,254 is identical with among the embodiment shown in Fig. 2 those flowing of the inlet portion 243 of compressor and export department 244, so will omit the detailed description to them.
Though below described two embodiment of two turbine centrifugal chilling units, the invention is not restricted to this.In other words, two evaporimeters can connect by serial or parallel connection, but and two condenser serial or parallel connections connections.In the case, it will be understood by those skilled in the art that, cold water is through first evaporimeter and second evaporimeter, cooling water through first condenser after through second condenser, first compressor that comprises cold-producing medium is connected to first condenser and second evaporimeter, and second compressor that comprises cold-producing medium is connected to second condenser and first evaporimeter, realizes two turbine centrifugal chilling units that the temperature difference of two compressors is equal to each other thus.
Though below illustrated and described exemplary embodiment, it will be understood by those skilled in the art that and to carry out the change of various forms and details, and do not deviate from the spirit and scope of the invention that claims limit.
In addition, can carry out many changes adapting to concrete condition or material at the content that this specification is taught, and not deviate from base region of the present invention.Therefore, wish that the present invention is not limited to the concrete exemplary embodiment that discloses as expection execution optimal mode of the present invention, otherwise the present invention will comprise falling all embodiment within the scope of the appended claims.