WO2005079957A1

WO2005079957A1 - Air conditioning method and air conditioning system

Info

Publication number: WO2005079957A1
Application number: PCT/JP2005/002305
Authority: WO
Inventors: Chikayoshi Sato
Original assignee: Chikayoshi Sato
Priority date: 2004-02-23
Filing date: 2005-02-16
Publication date: 2005-09-01
Also published as: JP2005233562A; TW200533871A

Abstract

A low-cost, high-performance air conditioning method capable of constantly keeping a dropwise condensation area, and an air conditioning system. An air conditioning method for dehumidifying an indoor air by cooling an indoor circulation air by an evaporator, wherein a condenser is disposed on the windward side of the evaporator, and the difference in temperature between the inlet air temperature of the evaporator and the evaporation temperature of the evaporator is kept at at least 24 ˚C to condense moisture in air dropwise on the surface of the evaporator and effect dehumidification. It may be favorable to dispose the evaporator tilted leeward so as to quickly remove drops deposited on the evaporator surface. This invention, capable of constantly keeping the dropwise condensation of an indoor air, can greatly increase dehumidification amount, and limit a rise in an indoor air temperature during a dehumidifying operation.

Description

Specification

Air conditioning method and air conditioning device

Technical field

The present invention relates to an air-conditioning method for cooling and dehumidifying indoor air with an evaporator, and more particularly, to an air-conditioning method and an air-conditioning method capable of greatly improving the amount of dehumidification as compared with a conventional dehumidification method. It relates to an air conditioner.

Background art

[0002] Conventionally, for example, there are various types of dehumidification methods of a dehumidifier such as a cooling type, a compression type, an absorption type and an adsorption type. Of these, the cooling type is also called the direct expansion coil type, and the principle of dehumidification is to reduce the saturated water vapor pressure by cooling the air with a compression refrigerator to condense the moisture in the air. This method has the advantage that the equipment cost is low, and is widely applied to home and commercial dehumidifiers.

[0003] As shown in Fig. 17, a conventional cooling-type dehumidifier includes an evaporator (cooler) 1 arranged on the leeward side, a condenser (radiator) 2 arranged on the leeward side, and an evaporator. It has a blower (not shown) that forms a convection airflow from 1 to the condenser 2, cools the indoor air with the evaporator 1 and dehumidifies it, and then reheats the air with the condenser 2 The configuration is common.

[0004] Usually, the amount of dehumidification can be determined from a psychrometric chart shown in Fig. 18. For example, when air at the standard point indicated by point I in the figure (temperature 27 ° C, relative humidity 60%) is cooled by evaporator 1, the air at the outlet at point O (temperature 17 ° C) In some cases, the dehumidification amount is calculated as xl- x2 = 3.67 gZkg (DR). “DR” means dry air.

[0005] The straight line connecting the points I and O is called the air operation line, and if the extension line is followed, it comes into contact with the saturation temperature curve, and the temperature F (5 ° C in this example) at this time It is called the dew point temperature (evaporation temperature). As the dew point temperature is lower, the temperature at the O point is lower, and a large amount of dehumidification can be obtained.

[0006] From this psychrometric chart, the sensible heat factor (SHF: Sensible Heat Factor) of the device can be obtained. The sensible heat ratio is the ratio of the sensible heat amount to the total heat amount when cooling a certain space, and sensible heat ratio = sensible heat amount QSZ (sensible heat amount QS + latent heat amount QL). Sensible heat quantity QS is air temperature Latent heat QL is the amount of heat required to condense the moisture in the air. Here, in the case of the above example, the sensible heat ratio is about 0.54, and the amount of heat required for temperature change (sensible heat QS) out of the heat of air is 54% of the total heat, and the remaining 46 % Is the latent heat, QL, to take up moisture.

[0007] In order to increase the amount of dehumidification by the cooling type dehumidification method, it is necessary to lower the minimum dew point temperature of the apparatus. However, with the conventional method of arranging heat exchange as described above and dehumidifying, it was impossible to lower the minimum dew point temperature of the device to 5 ° C or less.

[0008] Accordingly, the present applicant first arranges an evaporator and a condenser in this order from the windward side, cools the air flow to an evaporation temperature by an evaporator to remove moisture, and then converts the air flow into a condenser. A dehumidification method for reheating to a predetermined temperature in the above-mentioned manner, and dehumidification by dehumidifying moisture in the air stream by drop condensation on the surface of the evaporator has been proposed (see Patent Document 1 below).

[0009] In other words, in the conventional dehumidifying method, the condensate (moisture in the air) becomes film-wise condensation that covers the surface (condensation surface) of the evaporator in a film-like manner, and the heat transfer on the condensation surface is Since this is performed through the liquid film, this liquid film has a large heat transfer resistance (Fig. 19A). On the other hand, in the case of drop wise condensation, in which the condensed liquid covers the condensing surface in a droplet form, the area of the part where the air flow directly contacts the condensing surface is larger than in the case of film condensation, so that the heat transmission rate is lower. (Heat transfer coefficient) (Fig. 19B). Therefore, the condensation of water is promoted by the improvement of the heat transmission coefficient, and as a result, the dew point temperature of the apparatus is lowered, and the amount of dehumidification can be improved.

[0010] The prior art documents related to the invention of this application are as follows.

Patent Document 1: Japanese Patent Application Laid-Open No. 2002-130863

Non-patent document 1: Heat transfer engineering data revised 4th edition 7th edition Published by The Japan Society of Mechanical Engineers 1999 p. 151-p. 152

Non-Patent Document 2: Refrigeration and Air-Conditioning Handbook I Volume Basic Edition

Disclosure of the invention

Problems to be solved by the invention

[0012] In general, droplet condensation is a process that shows a higher heat transfer coefficient than film condensation. The phenomenon itself has not yet been sufficiently elucidated (see Non-Patent Document 1). It has been reported that the force of film-like condensation or droplet-like condensation depends on the surface properties of the above substances and solid walls (cooling surfaces) (see Non-Patent Document 2). Regarding the surface properties of the solid wall, the main focus is on the surface treatment for generating droplet-like condensation and the development of accelerators.

[0013] However, in this method, the manufacturing cost of the evaporator increases, and it becomes difficult to realize a low-cost e.g. It is also unknown how reliable the droplet condensation can be maintained over a long period of time. Corrosion of the evaporator surface (cooling surface) due to aging has been reported! Patent Document 1).

Therefore, the present invention has been made in view of the above problems, and provides an inexpensive and high-performance air-conditioning method and an air-conditioning apparatus capable of stably maintaining a droplet-shaped condensation area and suppressing a manufacturing cost. As an issue.

Means for solving the problem

[0015] In solving the above problems, the present inventor has determined that the difference between whether the form of condensation of water on the surface (cooling surface) of the evaporator is a film-like condensation, which is droplet condensation, The present inventors have found that the temperature difference between the inlet air temperature of the evaporator and the evaporation temperature of the evaporator has a great relationship, and have completed the present invention.

[0016] That is, according to the present invention, the condenser is arranged on the windward side of the evaporator, and the temperature difference between the inlet air temperature of the evaporator and the evaporation temperature of the evaporator is set to 24 ° C. or more. It is characterized in that moisture in the air is condensed in droplets on the surface of the vessel and dehumidified. At 23 ° C. or lower, a film-like condensed region is formed. At this temperature difference, it is difficult to form a condensed liquid droplet unless some treatment is performed on the cooling surface.

[0017] Thereby, the moisture in the air can be stably condensed in a droplet form, and the amount of dehumidification can be improved. Further, since no special treatment is required for the evaporator surface, the production cost can be suppressed.

[0018] In the dehumidifying method according to the present invention, a sensible heat ratio larger than that in the film condensation is obtained. In other words, most of the cooling capacity of the droplet condensation is used for the sensible heat, that is, the heat required for cooling the air, so that the function as the air conditioner can be satisfied at the same time.

[0019] The condenser arranged on the windward side of the evaporator preheats the inlet air temperature of the evaporator, and It has a function to give a temperature difference of 24 ° C or more between the inlet air temperature of the evaporator and the evaporator.

[0020] The heat transfer coefficient of droplet condensation is closely related to the size of the droplet on the condensation surface. The faster the vapor speed, the smaller the diameter of the separated droplet, and the smaller the diameter of the droplet, the smaller the heat transfer. The rate tends to increase. Therefore, in order to quickly and efficiently separate water droplets adhering to the cooling fin surface of the evaporator, it is preferable to arrange the evaporator so that the upper part of the evaporator is inclined to the leeward side. And the next water droplets are more likely to adhere, and the amount of dehumidification is improved.

On the other hand, by adopting a method in which a condenser is arranged on the lee side of the evaporator and the outlet air temperature of the evaporator is reheated by the condenser, a normal dehumidification meeting that does not lower the indoor air temperature is realized. Obtainable.

[0022] At this time, the condenser on the upwind side of the evaporator and the condenser on the downwind side of the evaporator divide one heat exchange and form a refrigerating circuit parallel to the evaporator. It is preferable to do so. As a result, the condensation load is reduced, the condensation temperature is reduced, and the evaporation temperature is also reduced.Therefore, the heat radiation of the entire apparatus can be reduced while increasing the temperature difference between the inflow air and the evaporator, and the amount of dehumidification can be improved. At the same time, an increase in the room temperature during the dehumidifying operation can be suppressed.

Meanwhile, in the above configuration example in which the condenser arranged on the lee side of the evaporator is a preheating condenser and the condenser arranged on the lee side of the evaporator is a reheating condenser, the evaporator is visible. By setting a non-condensing area with 100% heat, a heater can be composed of these three heat exchangers.

[0024] As an example of the operation method, the heat release ratio of the preheating condenser and the reheating condenser is set to 0.18: 0.82. By setting the condensing temperature to 60 ° C and the evaporator evaporating temperature to 12 ° C, the system operates at an outlet air temperature of 65 ° C against an inlet air temperature of 20 ° C.

The invention's effect

[0025] As described above, according to the present invention, moisture in the air can be stably condensed on the surface of the evaporator during the cooling operation or the dehumidifying operation. The dehumidification method using condensation and the dehumidification amount can be significantly improved compared to the conventional machine. Wear.

[0026] Further, according to the present invention, since droplet condensation can be realized without requiring a surface treatment for promoting droplet condensation on the evaporator, high reliability can be ensured for a long time. Can be. Further, since power consumption can be reduced as compared with the conventional air conditioner, an air conditioner with low cost and low power consumption can be provided.

[0027] Further, according to the air conditioner of the present invention, each of the cooling, dehumidifying, and heating operations can be performed by a single unit. Therefore, the present invention is configured as a substitute for a conventional air conditioner requiring an outdoor unit. It is possible.

Brief Description of Drawings

FIG. 1 is an overall view of an air conditioner 20 according to an embodiment of the present invention.

FIG. 2 is an arrangement configuration diagram of a heat exchanger of the air conditioner 20.

FIG. 3 is a refrigeration circuit diagram of the air conditioner 20.

FIG. 4 is a psychrometric chart illustrating one operation of the air conditioner 20.

FIG. 5 is a view showing a relationship between an evaporator inlet air temperature and an evaporation temperature.

FIG. 6 is a diagram illustrating a comparison of the amount of dehumidification between the invented machine and the conventional machine.

FIG. 7 is a perspective view of a heat exchanger when a refrigerator is configured with the invented machine.

FIG. 8 is a side view showing a modification of the arrangement of the heat exchangers of the air conditioner 20.

FIG. 9 is a diagram showing a relationship between a detached droplet diameter and a heat transfer coefficient in droplet condensation.

FIG. 10 is a diagram showing the relationship between the degree of supercooling of the surface and the heat flow rate in a drop condensation area.

FIG. 11 is a diagram illustrating another example of arrangement of an evaporator.

FIG. 12 is another layout diagram of the heat exchanger of the air conditioner 20.

FIG. 13 is a view for explaining still another arrangement example of the evaporator.

FIG. 14 is a diagram illustrating a design example of each heat exchanger during a heating operation of the air conditioner 20.

FIG. 15 is a Mollier chart of a refrigerant during a heating operation of the air-conditioning apparatus 20.

FIG. 16 is a diagram illustrating the air temperature and the refrigerant temperature during the heating operation of the air-conditioning apparatus 20.

FIG. 17 is a layout view of a heat exchanger of a conventional dehumidifier. FIG. 18 is a psychrometric chart of a conventional dehumidifier.

FIG. 19 is a diagram for explaining the difference between a condensation model based on film condensation and a condensation model based on droplet condensation.

Explanation of symbols

[0029] 20 air conditioner

21 1st (for preheating) condenser

22 Second (for reheating) condenser

23 Evaporator

24 body

24A air inlet

24B air outlet

25 blower

26 tank

27 compressor

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 show the configurations of an air conditioner 20 and heat exchangers 21 to 23 according to an embodiment of the present invention. First, the overall configuration of the air conditioner 20 will be described.

[0032] The air conditioner 20 in the present embodiment is configured as a handy-type household dehumidifier, a cooler or a heater, and mainly includes a first condenser (preheating condenser) 21 and a second condenser ( A condenser for reheating) 22, an evaporator 23, a blower 25, a compressor 27, and a main body 24 accommodating these devices.

[0033] The main body 24 has an air inlet 24A and an air outlet 24B. When the blower 25 is driven, a force of the air inlet 24A is generated toward the air outlet 24B, so that a flow of air is formed. I have. The first condenser 21 is disposed closest to the air intake port 24A, and the evaporator 23, the second condenser 22, and the blower 25 are disposed in order in the leeward direction. Below the main body 24, a tank 26 for storing the moisture in the air dehumidified by the evaporator 23, and a compressor 27 for circulating the refrigerant to the first and second condensers 21, 22 and the evaporator 23 are provided. Is contained. [0034] The first and second condensers 21, 22 and the evaporator 23, which are erected vertically, have the same configuration, and are arranged at equal pitches as shown in FIG. The radiating fin 38 includes a plurality of radiating fins 38 and a refrigerant circulation noise 39 disposed so as to penetrate the radiating fins 38. In the present embodiment, both the heat radiation fins 38 and the circulation pipes 39 are made of aluminum.

FIG. 3 is a piping configuration diagram of a refrigeration circuit of the air conditioner 20. The first and second condensers 21 and 22 divide one heat exchanger into two, and are connected in parallel to the upwind side and the downwind side of the evaporator 23, respectively.

[0036] The high-temperature and high-pressure refrigerant gas discharged from the compressor 27 is supplied to the first and second condensers 21 and 22 through the pipe 28, and releases heat to the surrounding air to condense and liquefy. The refrigerant flowing out of the first and second condensers 21 and 22 is supplied to an electronic expansion valve 30 via a pipe 29 to be decompressed, and further supplied to an evaporator 23 to remove heat from the surrounding air to evaporate and gasify. I do. Then, the refrigerant with the power of the evaporator 23 is supplied to the suction port of the compressor 27 through the pipe 31. The air conditioner 20 is operated by repeating the above refrigeration cycle.

With the above configuration, during the dehumidifying operation, the indoor air bl sucked from the air suction port 24A of the main body 24 is heated by passing through the first condenser 21, and is evaporated as the heated air b2 Container 23 is reached. The heated air b2 comes into contact with the cooling surface of the evaporator 23 (the surface of the radiation fins 38) to be dehumidified and cooled. The air b3 that has passed through the evaporator 23 is heated to the room temperature by the second condenser 22, and the heated dry air b3 is discharged into the room through the air outlet 24B of the main body 24. .

Next, an air conditioning method using the air conditioning apparatus 20 of the present embodiment configured as described above will be described.

[0039] [Dehumidification Z cooling operation]

In the present embodiment, a first condenser 21 for preheating is arranged on the windward side of the evaporator 23. With such a configuration, the air in the room is introduced into the first condenser 21 by driving the blower 25, and the air whose temperature has been raised by a predetermined temperature is cooled by the evaporator 23 to dehumidify the moisture. Then, it is reheated to a predetermined temperature by the second condenser 22 at the subsequent stage, and is discharged indoors.

[0040] By passing through the first condenser 21, the air evaporates at a predetermined temperature (for example, 5 ° C). Since the air comes into contact with the surface of the evaporator 23, the suction air comes into contact with the evaporator 23 with a larger temperature difference than when the preheat condenser 21 is not provided. In addition, the condensation temperature decreases due to the distribution of the condenser, and the dew point temperature decreases.

The decrease in dew point temperature will be described with reference to a psychrometric chart shown in FIG. Assuming that the room air is at a standard point (temperature 27 ° C, relative humidity 60%), in the above example, the first condenser 21 preheats to 32 ° C and then evaporator 23. Cooled. At this time, the operating line touches the saturation temperature curve at -1 ° C, and this temperature becomes the dew point temperature of the device. This makes it possible to significantly reduce the dew point temperature compared to a conventional dehumidifier (operation line shown by a broken line in the figure) in which a condenser is arranged on the windward side of the evaporator.

[0042] Therefore, in the air conditioner 20 of the present embodiment, the temperature difference between the inlet air temperature of the evaporator 23 and the evaporation temperature of the evaporator 23 is set to 24 ° C or more. I have. As described later, by providing a temperature difference of 24 ° C. or more between the inlet air temperature of the evaporator 23 and the evaporator 23, the water in the air can be condensed in a droplet form.

[0043] Generally, during the condensation process in which the vapor contacts the low-temperature solid surface and is cooled and liquefied! Formerly, film-like condensation in which the condensate spreads on the solid surface to form a thin liquid film, and droplet-like condensation in which the condensate does not spread on the solid surface and adheres in the form of droplets are known. As described above, droplet condensation shows a higher heat transfer coefficient than film condensation.

[0044] Table 1 shows the experimental results when the condensation form of moisture in the air was measured according to the temperature difference between the evaporator inlet air temperature and the evaporator evaporation temperature. To check the form of water condensation, check the surface of the evaporator. The observation was performed. Table 1 shows that when the temperature difference (ti te) between the evaporator inlet air temperature (ti) and the evaporator evaporation temperature (te) is 24 ° C or more, the moisture in the air drops. It can be seen that it is condensed.

[Table 1] t ί teti-te Condensation form Symbol in Fig. 5

Example 1 2 V,-s x: 27 ° C Drop 〇

Example 2 2 8: 4 V, 24 V Drop □

Example 3 Droplet Δ at 3 o 6 V 24

Comparative Example 1 2 7 V 1 9 Membrane ©

Comparative Example 2 2 7 X s 2

t ί: Evaporator inlet air temperature

t e: evaporation temperature

From the results in Table 1, a condensation area boundary diagram as shown in FIG. 5 can be created. In the figure, V represents the evaporator inlet air temperature (ti) on the vertical axis, and the evaporator evaporation temperature (te) on the horizontal axis. FIG. 5 shows Example 1 in Table 1 with white circles, Example 2 with squares, Example 3 with triangles, Comparative Example 1 with double circles, and Comparative Example 2 with black circles.

[0047] As shown in Fig. 5, when the temperature difference between the evaporator inlet air temperature and the evaporating temperature is 23 ° C or less, a film condensed region, when 23 ° C or more is a droplet condensed region, and around 23 ° C. It can be inferred that there exists a convective condensed zone boundary where the film-shaped condensed zone and the droplet-shaped condensed zone exist.

[0048] From the above results, by setting the temperature difference between the evaporator inlet air temperature and the evaporating temperature to 24 ° C or more, it is possible to stably condense the water in the air on the evaporator 23 surface. Becomes possible. Thereby, a higher dehumidification capacity can be obtained as compared with the conventional dehumidifier set in the film-form condensation area described with reference to FIG.

[0049] The operating conditions of the air conditioner 20 for realizing the above-described droplet-type condensation include, for example, a condensation test at 27 ° C and 60% of a standard dehumidifier for household use specified in JIS C9617. The evaporation temperature is set so that the difference between the evaporator inlet air temperature and the evaporation temperature is 24 ° C or less. The specifications of the first condenser 21 and the second condenser 22 are not limited to being the same, and the specifications may be different from each other. For example, a flow control valve or the like may be arranged in the first condenser 21 so that the first and second condensers 21 and 22 have different refrigerant flow rates.

[0050] Further, in the present embodiment, the first condenser 21 and the second condenser 22 are arranged on the upstream and downstream sides of the evaporator 23, so that the condensing capacity of the condenser 2 of the conventional dehumidifier is reduced. The condensing capacity is increased and the condensing load is reduced so that the capacity of the compressor 27 is not reduced. As a result, the condensation pressure (condensation temperature) can be lowered, so that the amount of dehumidification can be improved without lowering the refrigerating capacity, and an increase in the ambient temperature can be suppressed by reducing the condensation load. Furthermore, since the amount of circulating refrigerant is reduced, power consumption can be reduced.

[0051] Fig. 6 shows the amount of dehumidification performed in a prefabricated warehouse without temperature and humidity adjustment using the conventional home dehumidifier (Fig. 17). This is shown in comparison with the conventional machine shown in Fig. 1). Here, the solid line indicates the invented machine, and the one-dot chain line indicates the conventional machine.

In FIG. 6, points A1 and A2 indicate data of the invented device and the conventional device at a temperature of 22.5 ° C. and a relative humidity of 47.6%, respectively. Comparing the amount of dehumidification, the conventional machine is 19 OccZh, while the invented machine is 300 ccZh, which is 1.58 times that of the conventional machine (the power consumption is 0.79 times that of the conventional machine).

In the figure, points B1 and B2 are data for the inventor and the conventional machine at a temperature of 24.5 ° C and a relative humidity of 93.3% .The dehumidification amount is 520 cc Zh for the conventional machine and 950 cc Zh for the invented machine. This is 1.8 times that of the conventional model (the power consumption is 0.76 times that of the conventional model).

Further, in the figure, points C1 and C2 indicate the dehumidification amount of the invented device and the conventional device at the temperature of 27 degrees and the relative humidity of 60%, that is, the standard point. However, the details are not known because measurement was not actually performed at this point, but it is estimated that the invented machine has about twice the amount of dehumidification as compared to the conventional machine.

In the case of the droplet condensation, unlike the case of the film condensation, the sensible heat amount of the apparatus cannot be obtained from the psychrometric chart. However, the approximate calculation can be calculated from the conventional air formula from the evaporating temperature of the device, the evaporator inlet air temperature, and the evaporator outlet air temperature.

(Invention machine operating conditions)

Evaporator inlet air temperature (ti): 30 ° C

Evaporator outlet air temperature: 10 ° C

Specific volume of air at a temperature of 30 ° C and a relative humidity of 50%: 0.88 m ³ / kg

Specific heat of air: 0.24kcal / kg ° C Sensible heat quantity QS = 0.24X1.58X60X (1 / 0.88) X (30-10)

= 517kcal / h

Note that the air volume (1.58 mVmin.) Is a tentative set value, and the set value of the air volume does not always provide a sufficient amount of dehumidification, but is appropriately set according to the specifications.

[0055] (Conventional machine operating conditions)

In this example, the conventional machine of Experimental Example 4 in Table 1 is applied.

Evaporator inlet air temperature and humidity: 27 ° C 60%

Evaporator outlet air temperature: 20.5 ° C

Evaporation temperature: 8 ° C

Latent heat at an evaporation temperature of 8 ° C: 592.6kcal / kg

Condensing temperature: 43 ° C

Specific volume of air at a temperature of 27 ° C and a relative humidity of 60%: 0.855mVkg

Specific heat of air: 0.24kcal / kg ° C

Air volume: 1.60m / min.

Sensible heat value QS = 0.24X1.60X60X (1 / 0.855) X (27—20.5)

= 175.2kcal / h

Dehumidification amount: 0.263kg / h (6.3LZ days)

Latent heat QL = 0.263X592.6 = 155.8kcal / h

Sensible heat ratio SHF = 175.2 / (175.2 + 155.8)

= 175.2 / 331 = 0.53 (calculated value)

In the psychrometric chart, SHF is 0.53, which is almost the same as the calculated value.

[0056] Since the sensible heat is proportional to the temperature difference of the air, naturally, even if the same compressor is used, the design conditions are different, so that the amount of sensible heat is larger in the droplet condensation than in the film condensation. That is, the cooling capacity increases.

[Table 2] Film condensation Drop condensation

Compressor output 100 W 100 W

Total cooling capacity 3 3 1 kcal / h ―

Sensible heat 1 75.2 kcal / h 5 17 kcal h

Dehumidification amount 6.3 L Z day 8.0 L Z day

Latent heat 1 55.8 kcal / h-Latent heat 5 92 2.6 kcal / h 〜 50 0-kcal / h

[0058] As shown in Table 2, it can be seen that the sensible heat of the droplet condensation, that is, the heat required to cool the air increases. As a result, the amount of heat dissipated by the dehumidifier can be reduced, and the rise in room temperature can be easily controlled.

[0059] While the SHF of the current air conditioner is mostly around 0.7, the dehumidifier of the present invention has a large amount of sensible heat (cooling capacity) (around SHFO. 9), and thus can have a cooling function. Thus, the present invention can be configured as a completely new type of cooling device that can configure the cooling device only with the indoor unit without the need for the outdoor unit.

In this case, as shown in FIG. 7, a configuration in which only the preheating condenser 21 is arranged on the windward side of the evaporator 23 can constitute an air conditioner for cooling. Further, in the air-conditioning apparatus 20 of the present embodiment, for example, a valve (not shown) capable of shutting off the supply of the refrigerant to the second condenser 22 arranged on the leeward side is installed. It can be configured to supply the refrigerant only to the upper first condenser 21.

Subsequently, the relationship between the capacities of the evaporator 23 of the invented device and the evaporator 1 of the conventional device is confirmed by the following calculation formula from the theoretical design formula of the evaporator.

[0062] Qe = K-A-Td …… (1)

Td = (ti + to) / 2-te …… (2)

here,

Qe: Evaporator cooling capacity (kcalZh)

K: Heat transfer coefficient of evaporator (kcal / ° Cm ² h)

A: Effective area of air-side cooling surface of evaporator (m ² )

ti: Evaporator inlet air temperature (° C) to: Evaporator outlet air temperature (° C)

te: Evaporator evaporation temperature (° C)

[0063] As the design conditions of the invented machine, the same compressor as that of the conventional machine is used, and the cooling capacity is almost the same. The relationship between the cooling capacity Qel of the evaporator of the conventional machine and the cooling capacity Qe2 of the evaporator of the invention machine is Qel = Qe2.

Regarding the relationship between the heat transmission coefficient K1 of the conventional evaporator and the heat transmission coefficient K2 of the evaporator of the invented device, K1 is the heat transmission coefficient in the film condensation, and K2 is the heat transmission coefficient in the droplet condensation. The flow rate is KKK2.

Furthermore, regarding Td, from equation (2),

Tdl = (til—tol) Z2—tel,

If the invention machine is Td2 = (ti2—to2) Z2—te2,

til = 27. C, tol = 17. C, tel = 10. C,

ti2 = 32. C, to2 = 14. C, te2 = 7 ° C

Tdl = 12 ° C, Td2 = 16 ° C, and Tdl <Td2.

[0064] Therefore, from the equation (1), in order to satisfy Qel = Qe2, regarding the surface area A of the evaporator, when the conventional machine is Al and the inventor is A2, A1> A2. It can be seen that the capacity of the evaporator of the invented device must be smaller than the capacity of the evaporator of the conventional device.

As a result, when the cooling capacity of the invented machine and the conventional machine are the same, the evaporator 23 of the invented machine is configured as shown in FIG. 8, for example. In the figure, the same reference numerals are given to the portions corresponding to FIG. Reference numeral 14 in the figure denotes a shield for blocking the passage of air. In the illustrated example, the area of the evaporator 23 is configured to be smaller than the area of the first and second condensers 22, and is 3.5 times smaller than the area of the evaporator 1 of the conventional machine.

As a result, the amount of dehumidification can be improved with a smaller evaporation area (capacity) than before, and the evaporator and the air conditioner can be downsized.

Next, in the air-conditioning apparatus 20 of the present invention, the relationship between the amount of dehumidified droplet and the droplet condensed on the surface of the evaporator 23 will be examined.

[0067] The heat transfer coefficient of droplet condensation is closely related to the size of droplets on the condensation surface. Fig. 9 Fig. 10 shows the relationship between the heat transfer coefficient under droplet condensation and the diameter of detached droplets. Fig. 10 shows the condensation curve of water vapor at 1 atm (both figures are from Non-Patent Document 1). The condensation curve referred to here is a curve that shows how the heat flux changes when the degree of supercooling of the surface gradually increases on the condensation surface where droplet condensation occurs. (Non-Patent Document 1).

As shown in FIGS. 9 and 10, there is a tendency that the larger the vapor velocity is, the smaller the detached droplet diameter is, and the smaller the droplet diameter is, the larger the heat transfer coefficient is. Therefore, it is important in design to quickly release the droplet from the evaporator 23 while the water droplet is small. The wind speed also affects, but the flow direction of the wind and the inclination angle of the evaporator are also important items.

[0069] To efficiently and quickly separate water droplets adhering to the cooling fin surface of the evaporator at the shortest cooling surface passage distance, as shown in Figs. It is desirable that the evaporator be arranged in the same manner. This is because it is easy to presume that the water droplets are quickly released from the cooling surface force, so that the next water droplets are likely to adhere and the amount of dehumidification increases.

FIG. 11B is an example in which the evaporator is arranged perpendicular to the condenser arranged in the vertical direction. In this example, one condenser is used as both the leeward condenser and the leeward condenser of the evaporator.

[0071] On the other hand, Fig. 11C is an arrangement example in which the upper part of the evaporator is inclined to the leeward side. If the wind force and the droplet force are the same, the water droplet will flow down in the B direction, and if the wind force becomes stronger than the water force of the droplet, it will scatter and fall in the range of B—C. Although the transmission distance and time of water droplets on the cooling surface are second to those in Figs. 11A and 11B, this example is superior in terms of the compactness of the heat exchanger arrangement and design flexibility.

[0072] Therefore, the three heat exchangers (first condenser 21, evaporator 23 and second condenser 22) in the air conditioner 20 of the present invention are connected to the upper part of the evaporator 23 as shown in Fig. 12, for example. By disposing so that it is inclined to the second condenser 22 side downwind, it is possible to further reduce the dehumidifying efficiency by increasing the separating effect of the condensed liquid droplets while keeping the size of the device compact. Become. The inclination angle of the evaporator 23 can be appropriately selected according to the strength of the air flow (air volume), the surface area of the evaporator, and the like, and is 45 degrees in this example.

[0073] As shown in Fig. 13, a configuration example in which the upper part of the evaporator is tilted to the windward side is also conceivable. Force In this case, when the wind force and the volume force of the water droplet are the same, the water droplet on the evaporator flows in the direction of the arrow, and the water droplet overlaps, the diameter increases, and the separation efficiency deteriorates.

[Heating operation]

Next, the indoor heating function of the air-conditioning apparatus 20 of the present embodiment will be described.

In the present embodiment, an indoor heating function is performed using the configuration of the air conditioner 20 described above. This makes it possible to construct a heater using a gas-compression refrigerator that does not require an outdoor unit only by circulating indoor air. As a result, the heating efficiency can be increased because there is no problem of defrosting.

As the design conditions, referring to FIG.

(1) The evaporation temperature of the equipment at the inlet air dry bulb temperature of the heater at 20 ° C (wet bulb temperature of 15 ° C) and the relative humidity of 60% is about 12 ° C.

(2) In order to prevent drying during heating, a non-condensing area with 100% sensible heat (sensible heat ratio SHF = 1.00), not dehumidified by an evaporator.

(3) The air volume flowing through the three heat exchangers (first condenser 21, evaporator 23, second condenser 22) is the same.

(4) The relationship between the outlet air temperature and the condensing temperature is about 5 ° C due to the effect of the superheated area, so the condensing temperature should be 60 ° C with the outlet air temperature of 65 ° C.

A design example will be described with reference to a Mollier diagram (ph diagram) in FIG. 15 and a distribution diagram of air temperature in each region of the refrigerant in FIG. The conditions of the refrigeration cycle are as follows: refrigerant R410A, condensation temperature 60 ° C, evaporation temperature 12 ° C, superheat degree 20 ° C, supercooling degree 5 ° C.

Note that the design example is not limited to this.

[0078] (Enthalpy difference of each region of refrigerant)

(a) Enthalpy ratio in superheated area: 485—418 = 67kj / kg

(b) Enthalpy ratio in the saturation region: 418-305 = 113kj / kg

(c) Enthalpy ratio in liquid area: 305—295 = lOkjZkg

Total heat dissipation: 67 + 113 + 10 = 190kj / kg (Heat radiation ratio of each region of refrigerant)

(a) Heat dissipation ratio in the superheated area: 67Z 190 = 0.35

(b) Heat dissipation ratio in the saturation region: 113Z190 = 0.60

(c) Heat dissipation ratio in liquid area: 10Z190 = 0.05

(Air temperature in each region of refrigerant)

Design air temperature difference: 65 ° C-20 ° C = 45 ° C

(a) Air temperature rise in superheated area: 45 ° C x 0.35 (radiation share) = 15.8 ° C

(b) Air temperature rise in the saturation region: 45 ° C X 0.60 = 27.0 ° C

(c) Enthalpy ratio in liquid area: 45 ° C X 0.05 = 2.2 ° C

[0081] The flow directions of the refrigerant and the air are counterflow. This allows

(1) Heater inlet air temperature: 20 ° C

(2) Air temperature from the liquid area to the saturation area: 20 ° C + 2.2 ° C = 22.2 ° C

(3) Saturation zone outlet air temperature: 22.2 ° C + 27.0 ° C = 49.2 ° C

(4) Heater outlet air temperature: 49.2 ° C + 15.8 ° C = 65 ° C

Next, the distribution of the heat radiation of the first and second condensers 21 and 22 is estimated and examined.

Referring to FIG. 14, the temperature difference between the inlet and outlet air is

Evaporator (23): 30 ° C-20 ° C = 10 ° C

First condenser (21): 30 ° C-20 ° C = 10 ° C

Second condenser (22): 65 ° C-20 ° C = 45 ° C

[0084] (Amount of heat radiation) = (air volume) X (air temperature difference), since the air volume of the first and second condensers 21 and 22 is the same, the amount of heat radiation of the first and second condensers 21 and 22 Is proportional to the temperature difference. Assuming that the total heat release of the condenser is 1.00,

Heat dissipation of the first condenser 21: 10 ° CZ (10 ° C + 45 ° C) = about 0.18

Heat dissipation of the second condenser 22: 45 ° CZ (10 ° C + 45 ° C) = about 0.82

It becomes.

[0085] Here, the temperature conditions (standard conditions) of the JIS standard (JISC9612) of the room air conditioner at the time of heating are a room air temperature of 20 ° C and an outdoor air temperature of 7 ° C.

[0086] Therefore, according to the present embodiment, the arrangement of three heat exchangers and the circulation of room air In the case of heating, the temperature of the air flowing into the indoor evaporator is naturally higher than the standard condition of 7 ° C, and the evaporation temperature also increases, so the refrigerant circulation amount increases, and if the condensing pressure is the same, the compression ratio decreases. As a result, power consumption is reduced, and as a result, a heating effect with a large COP (heating capacity Z power consumption) is obtained.

[0087] The power described in the embodiment of the present invention is, of course, not limited to this, and various modifications can be made based on the technical idea of the present invention.

[0088] For example, in the above-described embodiment, one first condenser 21 for preheating is arranged on the windward side of the evaporator 23, but the first condenser 21 is divided into two instead. It may be installed on the windward side of the evaporator. This makes it possible to easily control the evaporator inlet temperature by controlling the supply of refrigerant to these two preheating condensers.

Further, during the heating operation, the design condition of the evaporator 23 is a non-condensing region with a sensible heat ratio of 100%. In order to maintain the non-condensing condition of the moisture in the air by the evaporator 23, for example, A humidity sensor is arranged at each of the inlet and outlet of the evaporator 23, and a compressor that can be controlled by an inverter is adopted as the compressor 27, and the compressor is controlled by an inverter based on the output difference between the pair of humidity sensors. Then, the non-condensing region of the evaporator 23 can be stably maintained.

Claims

The scope of the claims

[1] An air conditioning method for dehumidifying a room by cooling indoor circulating air with an evaporator, wherein a condenser is disposed on the windward side of the evaporator, and the inlet air temperature of the evaporator and the evaporation of the evaporator An air conditioning method, characterized in that a temperature difference between the temperature and the temperature is set to 24 ° C. or more, so that moisture in the air is condensed in a droplet form on the surface of the evaporator and dehumidified.

[2] The air conditioning method according to claim 1, wherein a condenser is arranged on the lee side of the evaporator, and outlet air of the evaporator is reheated by the condenser.

3. The air-conditioning method according to claim 1, wherein the evaporator is tilted to the leeward side.

[4] The room is heated by setting the evaporator in a non-condensing region having a sensible heat of 100%.

Item 2. The air conditioning method according to item 2.

[5] A main body having an air inlet and an air outlet formed therein, a condenser and an evaporator disposed inside the main body, and a compressor for circulating a refrigerant to the condenser and the evaporator.

A blower for forming a flow of air from the air inlet side to the air outlet side,

A condenser for preheating is arranged on the windward side of the evaporator, and the difference between the inlet air temperature of the evaporator and the evaporation temperature of the evaporator is set to 24 ° C or more during dehumidification or cooling operation.

An air conditioner characterized by V ヽ.

6. The air conditioner according to claim 5, wherein a condenser for reheating is disposed downstream of the evaporator.

7. The air conditioner according to claim 5, wherein the evaporator is inclined so as to incline toward the leeward side.

[8] The air conditioner according to claim 5, wherein the surface area of the evaporator is formed smaller than the surface area of the condenser.

9. The air conditioner according to claim 6, wherein a heating operation is enabled by setting the evaporator in a non-condensing region having a sensible heat of 100%.