US20190162427A1

US20190162427A1 - Air conditioning economizer

Info

Publication number: US20190162427A1
Application number: US16/264,984
Authority: US
Inventors: Tun-Ping TENG; Huai-En MO
Original assignee: National Taiwan Normal University NTNU
Current assignee: National Taiwan Normal University NTNU
Priority date: 2015-11-26
Filing date: 2019-02-01
Publication date: 2019-05-30
Also published as: TW201719082A; TWI579509B; US20170153028A1

Abstract

An air conditioning economizer includes a compressor, a condenser, a metering device, an evaporator generating condensed water during operation, a refrigerant pipe and a textile member. The refrigerant pipe is a loop pipe interconnecting the compressor, the condenser, the metering device and the evaporator, and includes a supercooling section interconnecting the condenser and the metering device. The textile member is capable of transferring moisture, is quick drying, covers the supercooling section and the metering device, and is adapted for absorbing the condensed water.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional application of U.S. patent application Ser. No. 15/156,763 (filed on May 17, 2016), which claims priority of Taiwanese Invention Patent Application No. 104139323, filed on Nov. 26, 2015.

FIELD

The disclosure relates to an air conditioning economizer, more particularly to an air conditioning economizer that is energy-efficient.

BACKGROUND

Due to the increasing demand for quality of life, air conditioners are becoming widely used in people's daily lives. With growing concerns over environmental issues, air conditioners with high energy efficiency ratios (EER) are highly appreciated. A conventional way of improving the energy efficiency ratio is to use a heat exchanger having a special structure or material. The conventional material such as Cu and Al has a high thermal conductivity coefficient, but there are also other materials with higher thermal conductivity coefficients. However, selecting a material of the heat exchanger that is a precious metal having higher thermal conductivity would result in increased manufacturing costs.

SUMMARY

Therefore, an object of the disclosure is to provide an air conditioning economizer that can alleviate at least one of the drawbacks of the prior art.
According to the disclosure, the air conditioning economizer includes: a compressor that is adapted for compressing a vapor refrigerant into a compressed vapor refrigerant; a condenser that is adapted for condensing the compressed vapor refrigerant into a liquid refrigerant, and that includes an exit end through which the liquid refrigerant exits; a metering device that is adapted for depressurizing the liquid refrigerant into a liquid-vapor mixture of depressurized refrigerant; an evaporator that is adapted for evaporating the liquid-vapor mixture of depressurized refrigerant into the vapor refrigerant, and that generates condensed water (w) during operation; a refrigerant pipe that is a loop pipe interconnecting the compressor, the condenser, the metering device, and the evaporator, and that includes a supercooling section interconnecting the exit end of the condenser and the metering device; and a textile member that is capable of transferring moisture and is quick drying, the textile member covering the supercooling section of the refrigerant pipe and the metering device, and being adapted for absorbing the condensed water (w).

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, of which:

FIG. 1 is a block diagram showing an air conditioning economizer of this disclosure;

FIG. 2 is a schematic view showing a first embodiment of the air conditioning economizer of this disclosure;

FIG. 3 is a schematic view showing a textile member of the first embodiment, the textile member covering a supercooling section of a refrigerant pipe of the first embodiment;

FIG. 4 is a schematic view showing the textile member being wound on the supercooling section of the first embodiment;

FIG. 5 is a pressure-enthalpy diagram of a refrigerant during operation in the air conditioning economizer;

FIG. 6 is a fragmentary schematic view showing a second embodiment of the air conditioning economizer of this disclosure;

FIG. 7 is a schematic view showing the textile member of the second embodiment, the textile member covering the supercooling section of the second embodiment; and

FIG. 8 is a schematic view showing the textile member being wound on the supercooling section of the second embodiment.

DETAILED DESCRIPTION

Before the disclosure is described in greater detail, it should be noted that where considered appropriate, reference numerals or terminal portions of reference numerals have been repeated among the figures to indicate corresponding or analogous elements, which may optionally have similar characteristics.
Referring to FIGS. 1 to 4, a first embodiment of an air conditioning economizer may be a window-type air conditioning economizer 10, and includes a compressor 1, a condenser 2, a fan 3, an evaporator fan 6, a metering device 4, an evaporator 5, a refrigerant pipe 7, a container 8, and a textile member 9. The compressor 1 is adapted for compressing a vapor refrigerant into a compressed vapor refrigerant. The condenser 2 is adapted for condensing the compressed vapor refrigerant into a liquid refrigerant, and includes an exit end 21 through which the liquid refrigerant exits. The fan 3 is used for generating an airflow toward the condenser 2. The metering device 4 is adapted for depressurizing the liquid refrigerant into a liquid-vapor mixture of depressurized refrigerant. The metering device 4 may be a capillary tube, an expansion valve, etc. The evaporator 5 is adapted for evaporating the liquid-vapor mixture of depressurized refrigerant into the vapor refrigerant. Moisture in the air is condensed into condensed water (w) by the evaporator 5 during operation (i.e., the evaporator 5 generates condensed water (w) during operation). The evaporator fan 6 is used for generating an airflow toward the evaporator 5. The refrigerant pipe 7 is a loop pipe interconnecting the compressor 1, the condenser 2, the metering device 4, and the evaporator 5, and includes a supercooling section 71 interconnecting the exit end 21 of the condenser 2 and the metering device 4. In this embodiment, the container 8 supports the compressor 1, condenser 2, and the evaporator 5. The condensed water (w) generated by the evaporator 5 is discharged into the container 8 and absorbed by the textile member 9.
Specifically, the textile member 9 is capable of transferring moisture and is quick drying. The textile member 9 covers the supercooling section 71 of the refrigerant pipe 7 and the metering device 4, and absorbs the condensed water (w).
The textile member 9 is made of a material selected from the group consisting of nylon, elastane, polyester, polypropylene, and combinations thereof. In certain embodiments, the textile member 9 is made of 64% nylon, 24% polyester, and 12% elastane. It should be noted that the composition of the textile member 9 should not be limited by what are disclosed herein, as long as the textile member 9 is capable of absorbing moisture and has rapid drying ability.
The rapid drying ability of the textile member 9 can be determined by measurement of a remained water ratio (RWR). To be more specific, the test conditions are set according to Chinese National Standards 5611 (CNS-5611), in which the textile member 9 is cut into a 5 cm×5 cm specimen, the temperature is controlled at 20±2° C., and the relative humidity is maintained at 65±2%. The dry weight (w_f) of the specimen is recorded, followed by using a micropipette to drip a 0.2 mL water droplet at 1 cm above the center of the specimen, and recording the wet weight (w₀) of the specimen. The weight of the specimen (w_i) is recorded at 1-minute intervals (alternatively, 10-minute intervals) continuously for an overall testing time of 100 minutes. The 40^thminute specimen weight is chosen as the assessment index for this test. The 40^thminute RWR (%) is calculated by (w_i−w_f)/(w₀−w_f)×100%. The textile member 9 has a remained water ratio not greater than 35%. In certain embodiments, the textile member 9 has a remained water ratio not greater than 13%.
The textile member 9 has a covering section 91 that covers the supercooling section 71 of the refrigerant pipe 7 and the metering device 4, and at least one extending section 92 that extends from the covering section 91 into the container 8 for absorbing the condensed water (w) that is discharged into the container 8. In this embodiment, the number of the extending section 92 is more than one, with each extending section 92 extending into the container 8, thereby achieving improved water-absorbing efficiency (see FIG. 3). Furthermore, in certain embodiments, the at least one extending section 92 of the textile member 9 may be connected to the container 8 (see FIG. 2). Referring to FIG. 4, in certain embodiments, the textile member 9 is a strip of fiber that is wound on the supercooling section 71 of the refrigerant pipe 7 to cover the supercooling section 71. Alternatively, the strip of fiber has multiple fiber parts that are sewn together. It should be noted that the attaching mechanism of the textile member 9 should not be limited to those disclosed above, and may be changed according to practical requirements.
FIG. 5 is a pressure-enthalpy diagram of a refrigerant during operation in the air conditioning economizer. L₁denotes a refrigeration cycle. L₂is a saturation curve. In an ideal vapor refrigeration cycle, the refrigerant enters the compressor 1 at point 1 as a saturated vapor and leaves the compressor 1 at point 2 as a superheated vapor. This process is termed adiabatic compression. Then, the refrigerant enters the condenser 2 as the superheated vapor at point 2 and leaves the condenser 2 as a saturated liquid at point 3, which is an isobaric heat rejection process. Afterwards, the refrigerant passes through the metering device 4, undergoes adiabatic expansion at constant enthalpy, and reaches point 4 as a liquid-vapor mixture. Finally, the refrigerant enters the evaporator 5, undergoes isobaric evaporation, and returns to point 1 as the saturated vapor. In an actual refrigeration cycle, the refrigerant may not be completely evaporated in the evaporator 5, and liquid compression may happen in the compressor 1, which may reduce the lifetime of the compressor 1. Therefore, the refrigerant is superheated at point 1 to ensure safety of the compressor 1. The actual compression process (point 1-2) involves frictional effects, which increase the entropy. In the point 2-3 process (the actual condensed process) and the point 4-1 process (the actual evaporated process), refrigerant friction causes a pressure drop. The refrigerant is subcooled somewhat before it enters the metering device 4. The point 3-4 is an adiabatic and isenthalpic process. The refrigerant is evaporated in the evaporator 5, and the heat exchange between the evaporator 5 and ambient air leads to the generation of the condensed water (w). The condensed water (w) is received in the container 8.
The condensed water (w) in the container 8 is absorbed by the extending section 92 of the textile member 9, and then permeated to the covering section 91. Through the heat exchange, including sensible heat and latent heat, between the supercooling section 71 of the refrigerant pipe 7, the metering device 4 and the condensed water (w), the temperatures of the supercooling section 71 and the metering device 4 and the refrigerant therein can be decreased.
Efficiency of the air conditioning economizer can be measured by the coefficient of performance (COP), which is proportional to the energy efficiency ratio (EER). The coefficient of performance of the air conditioning economizer is defined by (h₁−h₄)/(h₂−h₁), in which h₁, h₂, h₃, and h₄are respectively the enthalpy values of the refrigerant at points 1, 2, 3, and 4. Since the process from point 3 to point 4 is an adiabatic expansion process at constant enthalpy, the value of h₃equals h₄. Therefore, the coefficient of performance can be increased by increasing the value of h₁-h₄. In other words, the efficiency of the air conditioning economizer can be increased by increasing the degree of supercooling of the refrigerant, and therefore increasing the value of h₁-h₄. Moreover, by using the textile member 9 to cover the metering device 4, the energy loss of the refrigerant associated with flashing can be lowered. In addition, the condensed water (w) evaporated inside the air conditioning economizer can reduce the temperature of the airflow passing through the condenser 2, which is beneficial to heat dissipation of the condenser 2.
Referring to FIGS. 1 and 6, a second embodiment of the air conditioning economizer 10 is similar to the first embodiment, with differences disclosed hereinafter. The second embodiment is a split-type air conditioning economizer which includes an indoor unit 20, an outdoor unit 30, and a water guiding tube 201. The indoor unit 20 includes the evaporator 5 and the evaporator fan 6. The outdoor unit 30 includes the compressor 1, the condenser 2, the fan 3, an outdoor container 301 and the metering device 4. The condensed water (w) generated by the evaporator 5 of the indoor unit 20 is directed to the outdoor unit 30 by the water guiding tube 201 such that the condensed water (w) is absorbed by the textile member 9 that covers the supercooling section 71 of the refrigerant pipe 7. In certain embodiments, at least a part of the refrigerant pipe 7 that interconnects the indoor unit 20 and the outdoor unit 30 is covered with an insulation member 700 for preventing the heat of ambient environment from heating up the refrigerant in the refrigerant pipe 7.
In certain embodiments, the water guiding tube 201 has a discharge end 202 that is adjacent to the textile member 9. The condensed water (w) is directed to the water guiding tube 201, discharged from the water guiding tube 201 through the discharge end 202, and directly guided onto and absorbed by the textile member 9. In certain embodiments, the outdoor container 301 includes a box 301 a for receiving the condensed water (w) that flows through but is not absorbed by the textile member 9. The condensed water (w) is discharged from the water guiding tube 201 into the box 301 a, and the textile member 9 absorbs the condensed water (w) from the box 301 a.
Referring to FIGS. 7 and 8, in certain embodiments, the at least one extending section 92 extends from the covering section 91 into the box 301 a for absorbing the condensed water (w) in the box 301 a. The at least one extending section 92 of the textile member 9 may be connected to the box 301 a (see FIG. 6).
To sum up, the textile member 9 is capable of absorbing the condensed water (w) to cool the supercooling section 71 of the refrigerant pipe 7 and the metering device 4 via sensible heat transfer. With the rapid drying property of the textile member 9, the cooling efficiency of the air conditioning economizer can be further increased via latent heat transfer during evaporation of the condensed water (w). Therefore, the degree of supercooling of the refrigerant can be increased, thereby increasing the coefficient of performance and the energy efficiency ratio of the air conditioning economizer. Furthermore, the textile member 9 can be easily installed to cover the supercooling section 71, and therefore the air conditioning economizer of this disclosure is easy to manufacture and cost-efficient to maintain.
In the description above, for the purposes of explanation, numerous specific details have been set forth in order to provide a thorough understanding of the embodiment(s). It will be apparent, however, to one skilled in the art, that one or more other embodiments may be practiced without some of these specific details. It should also be appreciated that reference throughout this specification to “one embodiment,” “an embodiment,” an embodiment with an indication of an ordinal number and so forth means that a particular feature, structure, or characteristic may be included in the practice of the disclosure. It should be further appreciated that in the description, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects.
While the disclosure has been described in connection with what is (are) considered the exemplary embodiment(s), it is understood that this disclosure is not limited to the disclosed embodiment(s) but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.

Claims

What is claimed is:

1. An air conditioning economizer comprising:

a compressor that is adapted for compressing a vapor refrigerant into a compressed vapor refrigerant;

a condenser that is adapted for condensing the compressed vapor refrigerant into a liquid refrigerant, and that includes an exit end through which the liquid refrigerant exits;

a metering device that is adapted for depressurizing the liquid refrigerant into a liquid-vapor mixture of depressurized refrigerant;

an evaporator that is adapted for evaporating the liquid-vapor mixture of depressurized refrigerant into the vapor refrigerant, and that generates condensed water during operation;

a refrigerant pipe that is a loop pipe interconnecting said compressor, said condenser, said metering device, and said evaporator, and that includes a supercooling section interconnecting said exit end of said condenser and said metering device; and

a textile member that is capable of transferring moisture and is quick drying, said textile member covering said supercooling section of said refrigerant pipe and said metering device, and being adapted for absorbing the condensed water.

2. The air conditioning economizer as claimed in claim 1, wherein said textile member has a remained water ratio not greater than 35% determined according to Chinese National Standards-5611 (CNS-5611) at the 40^thminute.

3. The air conditioning economizer as claimed in claim 2, wherein said textile member is made of a material selected from the group consisting of nylon, elastane, polyester, polypropylene, and combinations thereof.

4. The air conditioning economizer as claimed in claim 1, further comprising a container that supports said condenser and said evaporator, the condensed water generated by said evaporator being discharged into the container and being absorbed by said textile member.

5. The air conditioning economizer as claimed in claim 4, wherein said textile member has a covering section that covers said supercooling section of said refrigerant pipe, and at least one extending section that extends from said covering section into said container for absorbing the condensed water that is discharged into said container.

6. The air conditioning economizer as claimed in claim 5, wherein said at least one extending section of said textile member is connected to said container.

7. The air conditioning economizer as claimed in claim 1, wherein said textile member is a strip of fiber that is wound on said supercooling section of said refrigerant pipe to cover said supercooling section.

8. The air conditioning economizer as claimed in claim 7, wherein said strip of fiber has multiple fiber parts that are sewn together.