Condenser architecture with multiple segments

Abstract

A heat exchanger system is provided. The heat exchanger system includes a vapor-compression circuit. The vapor compression circuit includes a compressor (11), an expansion valve (12), a condenser (13) fluidly interposed between the compressor and the expansion valve and an evaporator (14) fluidly interposed between the expansion valve and the compressor. The condenser includes a de-superheating segment (20) and a condensing segment (30). The condensing segment is receptive of a first liquid downstream from the de-superheating segment. The condensing and de-superheating segments are receptive of a second liquid in parallel. Flows of the second liquid into the de-superheating segment are controllable by a control valve (70) based on the temperature of flows of the second liquid exiting the de-superheating segment measured by a temperature sensor (60).

Description

BACKGROUND

[0001] The present invention relates to heat exchanger systems comprising a condenser having a de-superheating segment and a condensing segment.

[0002] In heat transfer systems, a condenser is a device used to condense a substance from its gaseous to its liquid state through a cooling process. In so doing, the latent heat that is given up by the substance is transferred through the condenser to a surrounding environment. Condensers can be made according to numerous designs, and come in many sizes ranging from rather small (hand-held) to very large (industrial-scale units used in plant processes).

[0003] In some cases, a condensing process employed by a condenser can be divided into two segments. The two segments are circuited in series on a refrigerant stream and in parallel on a secondary fluid stream. The first segment is used to decrease refrigerant temperatures down to a saturated temperature level. The second segment is used to condense and sub-cool the refrigerant.

[0004] CH 632080 discloses a heat pump installation comprising a compressor, a valve, a desuperheater and a condenser which are disposed in sequence to each other between the compressor and the valve, and an evaporator interposed between the valve and the compressor. A refrigerant flows from the compressor through the desuperheater and then through the condenser, and flows of water enter in parallel into the condenser and the desuperheater, respectively.BRIEF DESCRIPTION

[0005] According to an aspect of the invention, a heat exchanger system is provided according to claim 1. The present invention provides also a heat exchanger system according to claim 5.

[0006] Further preferred embodiments of the present invention are defined in the dependent claims.

[0007] These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The subject matter, which is regarded as the disclosure, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of the disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: FIG. 1 is a schematic illustration of a heat exchanger system in accordance with the present invention; FIG. 2 is a schematic illustration of circuiting of a condenser of the heat exchanger system of FIG. 1; FIG. 3 is a schematic illustration of circuiting of a condenser of the heat exchanger system of FIG. 1; FIG. 4 is a schematic illustration of a heat exchanger system in accordance with the present invention; FIG. 5 is a schematic diagram of a controller of the heat exchanger systems of FIGS. 1 and 4; and FIG. 6 is a flow diagram illustrating a method not according to the invention for operating a heat exchanger system in accordance with embodiments.

[0009] These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.DETAILED DESCRIPTION

[0010] As will be described below, a secondary fluid stream flow of a condenser is divided to feed a first segment and a second segment with a calculated and controlled split ratio. The split ratio can be set to optimize heat transfer efficiency and output water temperatures. The first and second segments are parts of a single heat exchanger with a circuiting architecture or two separate heat exchangers. In both cases, de-superheating and condensing processes are separated and thus make better use of heat transfer surfaces.

[0011] With reference to FIG. 1, a heat exchanger system 10 is provided. The heat exchanger system 10 includes a compressor 11, an expansion valve 12, a condenser 13 fluidly interposed between the compressor 11 and the expansion valve 12 and an evaporator 14 fluidly interposed between the expansion valve 12 and the compressor 11. The compressor 11 is operable to compress a saturated vapor therein and to output a highpressure and high-temperature superheated vapor toward the condenser 13. The condenser 13 causes the superheated vapor received from the compressor 11 to condense through thermal transfer with water, for example. The condenser 13 outputs the resulting condensed liquid toward the expansion valve 12 as a saturated liquid. The expansion valve 12 abruptly reduced a pressure of the saturated liquid and produces a relatively cold mixture. The liquid of this cold mixture is then evaporated in the evaporator 14 and the resulting saturated vapor is returned to the compressor 11.

[0012] With continued reference to FIG. 1 and with additional reference to FIGS. 2 and 3, the condenser 13 includes a first or de-superheating segment 20 and a second or condensing segment 30. The de-superheating segment 20 and the condensing segment 30 are separate from one another. During operations of the condenser 13, the condensing segment 30 receives a first liquid, such as refrigerant being passed or cycled through the heat exchanger system 10, downstream from the de-superheating segment 20. As such, the de-superheating segment 20 and the condensing segment 30 are disposed in series with respect to the first liquid. While the operations proceed, the de-superheating segment 20 and the condensing segment 30 are also receptive of a second liquid, such as water, in parallel. At least the flows of the second liquid into the de-superheating segment 20 are controllable based on characteristics of flows of the second liquid exiting the de-superheating segment 20.

[0013] As shown in FIGS. 2 and 3 the condenser 13 may also include a first circuit 130 (see FIG. 2) that traverses the de-superheating segment 20 and the condensing segment 30 with a serial arrangement as well as a second circuit 131 (see FIG. 3) that traverses the de-superheating segment 20 and the condensing segment 30 with a parallel arrangement.

[0014] As shown in FIGS. 1 and 2, the first circuit 130 is formed of a first header 201, which includes a first inlet 2010 and a first outlet 2011, a second header 202, a separation plate 203 and first and second passes 204 and 205 fluidly connecting the first header 201 and the second header 202. The first inlet 2010 is receptive of the first liquid from the compressor 11 and the outlet 2011 is disposed to permit the first liquid to exit toward the expansion valve 12. The separation plate 203 is disposed in the first header 201 proximate to the first inlet 2010 and defines the first passes 204 as the de-superheating segment 20 and the second passes 205 as the condensing segment 30. That is, the first liquid enters the first header 201 of the condenser 13 via the first inlet 2010 and is forced to flow through the first passes 204 toward the second header 202 by the separation plate 203. The first liquid then flows from the second header 202, through the second passes 205 and back toward the first header 201 whereupon the first liquid exits the condenser 13 via the first outlet 2011.

[0015] As shown in FIGS. 1 and 3, the second circuit 131 is formed of a first header 301, which includes a first inlet 3010 and a second inlet 3011, a second header 302, which includes a first outlet 3020 and a second outlet 3021 (the first and second outlets 3020 and 3021 may be superimposed on another or separate from one another), a separation plate 303 and first and second passes 304 and 305 fluidly connecting the first header 301 and the second header 302. The first and second inlets 3010 and 3011 are receptive of the second liquid in parallel and the second liquid exits through the first and second outlets 3020 and 3021 in parallel. The separation plate 303 is disposed at least in the first header 301 proximate to the first inlet 3010 and defines the first passes 304 as the de-superheating segment 20 and the second passes 305 as the condensing segment 30. That is, the second liquid enters the first header 301 of the condenser 13 via the first and second inlets 3010 and 3011 and is forced to flow through the first and second passes 304 and 305 in parallel toward the second header 302 by the separation plate 303. The second liquid then flows out of the second header 302 via the first and second outlets 3020 and 3021.

[0016] As shown in FIG. 1, the heat exchanger system 10 further includes a flow splitter 40, a flow mixer 50, a sensor 60 and a controllable valve 70.

[0017] The flow splitter 40 is disposed upstream from the de-superheating segment 20 and the condensing segment 30 and is disposed and configured to split a flow of the second liquid into first and second parallel flows of the second liquid 41 and 42 for respective entry the de-superheating segment 20 and the condensing segment 30 in parallel. The flow mixer 50 is disposed downstream from the de-superheating segment 20 and the condensing segment 30 and is disposed and configured to mix third and fourth parallel flows of the second liquid 51 and 52 respectively exiting the de-superheating segment 20 and the condensing segment 30 in parallel.

[0018] The sensor 60 may be provided as a single sensor 61 that is interposed between the de-superheating segment 20 and the flow mixer 50 such that the single sensor 61 is disposed to measure the characteristics of the third flow of the second liquid 51 exiting the de-superheating segment 20. In accordance with embodiments, the single sensor 61 may include or be provided as a temperature sensor. The controllable valve 70 is interposed between the flow splitter 40 and the de-superheating segment 20 and is controllable to adjust an amount of the first flow of the second liquid 41 entering the de-superheating segment 20 based on readings (e.g., temperature readings of the flows of the third flow of the second liquid 51 exiting the de-superheating segment 20) of the sensor 60. The controllable valve 70 may include or be provided at least as a controllable bi-directional valve or a two-way valve controllable 71.

[0019] With reference to FIG. 4 and in accordance with alternative embodiments, the sensor 60 is provided as first sensors 62 and 63 and as a second sensor 64. The first sensors 62 and 63 are interposed between the flow mixer 50 and each of the de-superheating segment 20 and the condensing segment 30 such that the first sensors 62 and 63 are disposed to measure the characteristics of the third and fourth flows of the second liquid 51 and 52 exiting the de-superheating segment 20 and the condensing segment 30, respectively. The second sensor 64 is disposed upstream of the de-superheating segment 20 such that the second sensor 64 is disposed to measure characteristics of flows of the first liquid entering the de-superheating segment 20 on the first circuit 130. In accordance with embodiments, the first sensors 62 and 63 and the second sensor 64 may each include or be provided as temperature sensors. The controllable valve 70 is interposed between the flow splitter 40 and each of the de-superheating segment 20 and the condensing segment 30 and is controllable to adjust an amount of the first and second flows of the second liquid 41 and 42 entering the de-superheating segment 20 and the condensing segment 30 based on readings (e.g., temperature readings of the flows of the third and fourth flows of the second liquid 51 and 52 exiting the de-superheating segment 20 and the condensing segment 30 and temperature readings of the flows of the first liquid into the de-superheating segment 20) of the first sensors 62 and 63 and of the second sensor 64. The controllable valve 70 may include or be provided at least as a controllable multi-directional valve or as a three-way controllable valve 72.

[0020] With reference to FIG. 5, the heat exchanger system 10 of FIGS. 1 and 4 may also include a controller 501. As shown in FIG. 5, the controller 501 includes a processing unit 502, a memory unit 503, a networking unit 504 and a servo control unit 505. The processing unit 502 is receptive of readings from the single sensor 61 (see FIG. 1) or from the first sensors 62 and 63 and the second sensor 64 (see FIG. 4) by way of the networking unit 504. The processing unit 502 also controls operations of the bi-directional or two-way controllable valve 71 (see FIG. 1) or the multi-directional or three-way controllable valve 72 (see FIG. 4) by way of the servo control unit 505. The memory unit 503 has executable instructions stored thereon, which are readable and executable by the processing unit 502. When the executable instructions are read and executed by the processing unit 502, the executable instructions cause the processing unit 502 to analyze the readings received by way of the networking unit 504 and to control the operations of the bi-directional or two-way controllable valve 71 or the multi-directional or three-way controllable valve 72 based on results of that analysis.

[0021] For example, for the heat exchanger system 10 of FIG. 1, in an event that the temperature of the third flow of the second liquid 51 is deemed too low or too high by the processing unit 502, the processing unit 502 could instruct the servo control unit 505 to open or close the bi-directional or two-way controllable valve 71 to increase or decrease a magnitude of the first flow of the second liquid 41.

[0022] As another example, for the heat exchanger system 10 of FIG. 4, in an event that the temperatures of the third and fourth flows of the second liquid 51 and 52 are deemed too low / high or too high / low by the processing unit 502, the processing unit 502 could instruct the servo control unit 505 to operate the multi-directional or three-way controllable valve 72 to increase or decrease (or vice versa) relative magnitudes of the first and second flows of the second liquid 41 and 42.

[0023] With reference to FIG. 6, a method of operating a heat exchanger, such as the condenser 13 described above, is provided. As shown in FIG. 6, the method includes directing a first liquid through first and second segments in series (block 601), directing a second liquid through the first and second segments in parallel, respectively (block 602), measuring characteristics of at least flows of the second liquid exiting the first segment (block 603) and controlling at least an amount of the second liquid permitted to enter the first segment based on readings derived from the measuring (block 604).

[0024] Benefits of the features described herein are the sub-dividing of de-superheating and sub-cooling to increase maximum water temperatures for output water that a system can provide (e.g., about 1.5K to 3K or about equivalent to 3% to 5% energy savings). The division of the condensing process also allows for specific sizing and design of a heat exchanger which can then be dedicated toward achieving a specific heat transfer mode. Optimized control also the system to operate with improved performance regardless of ambient conditions and protects against water vapor generation.

Claims

1. A heat exchanger system (10), comprising: a vapor-compression circuit comprising a compressor (11), an expansion valve (12), a condenser (13) fluidly interposed between the compressor (11) and the expansion valve (12) and an evaporator (14) fluidly interposed between the expansion valve (12) and the compressor (11), wherein the condenser (13) comprises a de-superheating segment (20) and a condensing segment (30), the condensing segment (30) being receptive of a first liquid downstream from the de-superheating segment (20), the condensing and de-superheating segments (20, 30) being receptive of a second liquid in parallel, and flows of the second liquid into the de-superheating segment (20) being controllable based on characteristics of flows of the second liquid exiting the de-superheating segment (20), and in that the heat exchanger system (10) further comprises a flow splitter (40) for the second liquid disposed upstream from the de-superheating and condensing segments (20, 30); a flow mixer (50) for the second liquid disposed downstream from the de-superheating and condensing segments (20, 30); a sensor (60) interposed between the de-superheating segment (20) and the flow mixer (50) to measure the characteristics of the flows of the second liquid; and a controllable valve (70) interposed between the flow splitter (40) and the de-superheating segment (20), the controllable valve (70) being controllable to adjust an amount of the second liquid entering the de-superheating segment (20) based on readings of the sensor (60).

2. The heat exchanger system (10) according to claim 1, further comprising a first liquid and a second liquid, wherein the first liquid comprises refrigerant and the second liquid comprises water.

3. The heat exchanger system (10) according to claim 1, wherein the controllable valve (70) comprises at least a controllable bi-directional valve (71).

4. The heat exchanger system (10) according to any one of the precedings claims, further comprising a controller (501) configured to control operations of the controllable valve (70).

5. A heat exchanger system (10), comprising: a vapor-compression circuit comprising a compressor (11), an expansion valve (12), a condenser (13) fluidly interposed between the compressor (11) and the expansion valve (12) and an evaporator (14) fluidly interposed between the expansion valve (12) and the compressor (11), wherein the condenser (13) comprises a de-superheating segment (20) and a condensing segment (30), the condensing segment (30) being receptive of a first liquid downstream from the de-superheating segment (20), the condensing and de-superheating segments (20, 30) being receptive of a second liquid in parallel, and flows of the second liquid into the de-superheating segment (20) being controllable based on characteristics of flows of the second liquid exiting the de-superheating segment (20), and in that the heat exchanger system (10) further comprises: a flow splitter (40) for the second liquid disposed upstream from the de-superheating and condensing segments (20, 30); a flow mixer (50) for the second liquid disposed downstream from the de-superheating and condensing segments (20, 30); first sensors (62, 63) interposed between the flow mixer (50) and each of the de-superheating and condensing segments (20, 30), respectively, to measure the characteristics of the flows (51, 52) of the second liquid exiting the de-superheating element (20) and the condensing segment (30), respectively; a second sensor (64) disposed upstream of the de-superheating segment (20) to measure characteristics of flows of the first liquid entering the de-superheating segment (20); and a controllable valve (70) interposed between the flow splitter (40) and each of the de-superheating and condensing segments (20, 30), the controllable valve (70) being controllable to adjust an amount of the second liquid entering the de-superheating and condensing segments (20, 30) based on readings of the first sensors (62, 63) and the second sensor (64).

6. The heat exchanger system (10) according to claim 5, further comprising a controller (501) configured to control operations of the controllable valve (70).

7. The heat exchanger system (10) according to claim 5, wherein the controllable valve (70) comprises a controllable multi-directional valve (72).

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