Outside air handling air conditioner

Abstract

This invention provides an energy-saving, space-saving, and low-cost external air conditioning unit. The unit comprises an exhaust path for discharging return air from an indoor space to the outside, and an air supply path for supplying outside air to the indoor space. On the air supply path side, a total heat exchanger is arranged at the front end and a dehumidifying impeller at the rear end, following the sequence of outside air passage. The total heat exchanger and the dehumidifying impeller span the exhaust path and the air supply path. In the total heat exchanger, total heat exchange occurs between the return air from the indoor space and the outside air. In the dehumidifying impeller, latent heat exchange occurs between the return air that has undergone total heat exchange and the outside air. In the air supply path, a blower is arranged on the air supply path side between the total heat exchanger and the dehumidifying impeller. Furthermore, the external air conditioning unit includes a heat pump circuit that performs heat exchange between the outside air passing through the air supply path side of the total heat exchanger and the exhaust air passing through the exhaust path side of the dehumidifying impeller. By simplifying the equipment, eliminating the need for outdoor units, and adopting a modular design, the total cost of the equipment can be reduced, and on-site construction costs and construction periods can be shortened after the equipment is installed.

Description

Technical Field

[0001] This invention relates to an outdoor air handling air conditioner (hereinafter referred to as "outdoor air handling unit") that can adjust the temperature and humidity of outdoor air with less energy by using a total heat exchanger and a passive dehumidifier impeller. The passive dehumidifier impeller does not use an external heat source during regeneration, but utilizes the relative humidity difference between two or more airflows. Background Technology

[0002] External air conditioning units used in office buildings or commercial buildings are used for the following purposes: to adjust the temperature and humidity of indoor air so that the temperature and humidity of the air supplied to the indoor air conditioning unit or the like are appropriate based on the temperature and humidity of the outside air. By reducing indoor humidity, the comfort level of the indoor space is improved, even at the same temperature.

[0003] For example, as such an external air conditioning unit, there is the air conditioner described in Patent Document 1, which consists of a total heat exchanger and a dehumidifying impeller. Figure 1 As shown, Patent Document 1's outdoor air conditioning unit includes an exhaust duct that discharges return air from the indoor space to the outside, and an air supply duct that supplies outside air to the indoor space. Furthermore, on the air supply duct side, a total heat exchanger is arranged at the front end and a dehumidifying impeller is arranged at the rear end, following the order in which the outside air passes. It also includes a heat pump circuit that performs heat exchange between the outside air and the return air after total heat exchange. In the total heat exchanger, total heat exchange occurs between the outside air on the air supply duct side and the return air on the exhaust duct side after passing through the dehumidifying impeller; in the dehumidifying impeller, latent heat exchange occurs between the outside air on the air supply duct side after passing through the total heat exchanger and the return air from the exhaust duct side of the indoor space. Since the dehumidifying impeller does not require a regenerative heat source, it is energy-saving; and since an outdoor unit is not required, it saves space and has low cost.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2020-12602 Summary of the Invention

[0005] The external air conditioning unit described in Patent Document 1 uses return air from the room to suppress initial and operating costs. However, the pursuit of further high performance, space saving, and low cost requires a device with high energy efficiency that achieves climate neutrality.

[0006] In the external air conditioning unit described in Patent Document 1, ion exchange resin is used as the adsorbent material for the dehumidification rotor, and there is no transfer of odorous gases from the return air to the supply air. However, the supply fan 8, which acts as a processing fan, is located behind the dehumidification rotor, thus creating a negative pressure on the supply air path side. This results in a pressure balance that is prone to leakage from the exhaust air path side to the supply air path side. Therefore, there is a concern that odorous gases contained in the return air from the room may transfer to the supply air, and reducing leakage from the return air path side or odorous gas transfer from the return air becomes a challenge.

[0007] Furthermore, the bypass passage A of the external control unit in Patent Document 1 is designed to stabilize the heat pump circuit and can directly deliver outside air to the exhaust side. In summer, to ensure the heat dissipation of the heat pump, for example, one-third of the outside air introduced into the supply air circuit is delivered to the exhaust side through bypass passage A. However, under heavy loads, there is a problem of insufficient heat exchange. The exhaust side fan 13 serves as both exhaust air supply and supply air introduction. When adjusting the heat balance of the heat pump circuit at the exhaust temperature EA, complex control is required to control the heat exchanger 14 in conjunction with the fan 13 in the airflow adjustment device 15.

[0008] Furthermore, Patent Document 1 does not describe operation during the transition season. During the transition season, the operation of the total heat exchange rotor 3 and the passive dehumidification rotor 6 is stopped, and only air supply is performed. In the air supply path, outside air passes through two rotors, thus increasing pressure loss and power consumption of the air supply fan 8, which acts as the processing fan. Moreover, the air volume on the air supply side is controlled only by the air volume adjustment device 1 or the air supply fan 8 located in front of the total heat exchange rotor 3, making it impossible to make fine adjustments to the air volume passing through each rotor. Therefore, it is difficult to say that operation during the transition season has been considered.

[0009] In order to solve the problems described above, the object of the present invention is to provide an external heat exchanger that has a total heat exchanger and a passive dehumidification impeller that does not require a regenerated heat source, and achieves cooling and heating only by means of a heat pump. Compared with the external heat exchanger described in Patent Document 1, it saves space and has a lower cost (see the comparative examples described below).

[0010] To address the aforementioned issues, the external control mechanism of the present invention comprises an exhaust path for discharging return air from an indoor space to the outside and an air supply path for supplying outside air to the indoor space. On the air supply path side, a total heat exchanger is arranged at the front end in the order in which outside air passes, and a dehumidifying impeller is arranged at the rear end. The total heat exchanger and the dehumidifying impeller span the exhaust path and the air supply path. In the total heat exchanger, total heat exchange occurs between the return air from the indoor space and the outside air. In the dehumidifying impeller, latent heat exchange occurs between the return air that has undergone total heat exchange and the outside air. In the air supply path, a blower is arranged on the air supply path side between the total heat exchanger and the dehumidifying impeller. Furthermore, the external control mechanism includes a heat pump circuit that performs heat exchange between the outside air passing through the air supply path side of the total heat exchanger and the exhaust air passing through the exhaust path side of the dehumidifying impeller.

[0011] Invention Effects

[0012] The external humidification unit of the present invention is configured as described above, using a total heat exchanger and a dehumidifying impeller, and can complete both cooling and heating using only a heat pump. Since all refrigeration equipment is assembled within a chassis, an outdoor unit is unnecessary, reducing the overall cost of the device. Furthermore, it eliminates the need for on-site work such as hot / cold water piping or refrigerant piping installation, external wiring, and the need for a dedicated outdoor unit location, thus reducing engineering costs and shortening the construction period. Being packaged in one unit does not affect existing equipment, allowing for replacement by introducing new equipment or updating existing systems. Moreover, it eliminates the need for a regenerative heat source for the dehumidifying impeller; by utilizing a total heat exchanger for total heat exchange between the return air (RA) and the outside air (OA), the humidification / dehumidification effect is improved, resulting in energy savings and high performance. Furthermore, by using ion exchange resin as the adsorption material for the impeller and optimizing the configuration of the supply fan, the transfer of odorous gases contained in the return air to the supply air can be further reduced.

[0013] The external adjustment unit of this invention is thinner than the conventional external adjustment unit of Patent Document 1, thus being more compact and space-saving. Furthermore, by employing a segmented unit structure, a configuration method suitable for integrated or segmented installation locations can be selected, offering flexibility and excellent transportability and installation operability. Moreover, due to its symmetrical design, it can also accommodate left-right reverse configurations, thereby shortening delivery time. Therefore, it can also address upgrade projects of existing equipment that were difficult to implement due to mismatched unit sizes in the conventional external adjustment unit of Patent Document 1.

[0014] Furthermore, the external air conditioning unit of this invention can automatically switch between the total heat exchanger, dehumidifier impeller, heat pump, bypass, etc., according to the operating mode, detect the temperature and humidity of the outside air, and automatically control it to meet the indoor air supply requirements. Therefore, it can operate stably throughout the year, which helps to improve energy efficiency. In the external air conditioning unit of this invention, dehumidification is performed through the dehumidifier impeller in summer, thus reducing the load on the cooling coils compared to dehumidification through cooling coils alone. By providing a bypass path for the total heat exchanger and dehumidifier impeller on the air supply side, power consumption during transitional seasons can be reduced. Attached Figure Description

[0015] Figure 1 This is a flowchart of the external adjustment machine in Patent Document 1.

[0016] Figure 2 This is a flowchart of the external dispatching machine of the present invention.

[0017] Figure 3 This is a diagram showing the unit structure of the external adjustment machine of the present invention.

[0018] Figure 4 This is a flowchart illustrating a comparative example in which the humidifier 11 is installed on the air supply side rather than the exhaust side in the external control unit of Patent Document 1.

[0019] Figure 5 The figure shows the performance of embodiments and comparative examples of the external adjustment machine of the present invention.

[0020] Figure 6 These are the test results related to Example 4 of the external adjustment machine based on the present invention.

[0021] Figure 7 This is a diagram illustrating an example of the structure of a heat pump circuit when the external control unit of the present invention is configured as a high-airflow type. Detailed Implementation

[0022] The external control unit of this invention is designed and structured with energy efficiency and miniaturization in mind. Hereinafter, according to... Figure 2 The embodiments of the external dispatching machine of the present invention will be described in detail.

[0023] The external air conditioning unit of the present invention includes an exhaust path B for discharging return air from an indoor space to the outside, and an air supply path C for supplying outside air to the indoor space. Furthermore, on the air supply path C, a total heat exchange rotor 3, serving as a total heat exchanger, is installed at the front end, and a dehumidification rotor 6 is installed at the rear end, following the order in which the outside air passes. In the total heat exchange rotor 3, total heat exchange occurs between the return air from the indoor space and the outside air; in the dehumidification rotor 6, latent heat exchange occurs between the return air that has undergone total heat exchange and the outside air. Moreover, on the air supply path C side, a heat exchanger 5 is installed at the outlet side of the total heat exchange rotor 3 and the inlet side of the dehumidification rotor 6; on the exhaust path B side, an exhaust path heat exchanger 14 is installed at the outlet side of the dehumidification rotor 6. It is configured as a heat pump circuit having a heat exchanger 5 on the gas supply side, a heat exchanger 14 on the exhaust side, and a compressor 16. The heat pump circuit enables the outside air passing through the total heat exchange wheel 3 on the gas supply side to exchange heat with the exhaust air passing through the dehumidification wheel 6 on the exhaust side.

[0024] (Total heat exchanger)

[0025] The total heat exchange rotor 3 is a rotor-shaped component made by corrugating aluminum foil or other sheets, and carries adsorption materials such as silica gel or ion exchange resin to absorb moisture. In this embodiment, ion exchange resin is used to prevent odor from transferring between the return air and the supply air. The total heat exchange rotor 3 is configured to span the exhaust path B, which discharges the return air RA from the indoor space (not shown) as exhaust EA, and the supply air C, which supplies the outdoor air OA to the indoor space as supply air SA, and is rotated by a gear motor (not shown). The bypass passage E bypasses the inlet and outlet sides of the total heat exchange rotor 3 in the supply air path C, and the airflow of the outdoor air OA passing through the bypass passage E is adjusted by the airflow adjustment device 26.

[0026] (Dehumidifier)

[0027] The dehumidifying rotor 6 is a component made by corrugating porous sheets of inorganic fibers such as glass fiber, and carrying adsorbent materials such as silica gel, zeolite, or ion exchange resin to absorb moisture. In this embodiment, ion exchange resin is used to prevent odor from transferring between the return air and the supply air. Furthermore, the dehumidifying rotor 6 is a passive dehumidifying rotor that does not require a regeneration heat source. The dehumidifying rotor 6 is configured to span an exhaust path B that discharges return air RA from the indoor space as exhaust EA and an air supply path C that supplies outside air OA to the indoor space as supply air SA, and is rotated by a geared motor (not shown). A bypass passage F bypasses the inlet and outlet sides of the dehumidifying rotor 6 in the air supply path C, and the airflow through the bypass passage F is adjusted by the airflow adjustment device 27.

[0028] (Heat pump loop)

[0029] The heat pump circuit includes a heat exchanger 5 on the gas supply side (such as a heat exchange coil), a heat exchanger 14 on the exhaust side, a compressor 16 for compressing the refrigerant, and an expansion valve (not shown) for controlling the expansion of the refrigerant. It performs refrigerant expansion / compression and heat exchange, moving heat from the low-temperature region to the high-temperature region. Heat exchange occurs between the outside air OA on the gas supply side (C side) passing through the total heat exchange impeller 3 and the exhaust air EA on the exhaust side (B side) passing through the dehumidification impeller 6. That is, the heat energy cooled / heated in the gas supply side heat exchanger 5 is dissipated / absorbed by the heat exchanger 14 on the exhaust side. The gas supply side heat exchanger 5 and the exhaust side heat exchanger 14 function as either evaporators or condensers, depending on the conditions.

[0030] The bypass passage D is located on the outlet side of the dehumidifying impeller 6 in the exhaust passage B, in front of the heat exchanger 14 on the exhaust side, to directly introduce outside air in order to stabilize the heat pump circuit. Outside air OA can be directly introduced into the exhaust EA through the bypass passage D using an airflow adjustment device 25, such as a volume damper (VD, MD), a variable air volume control device (VAV), or a constant air volume control device (CAV). In summer, to ensure the heat dissipation of the heat pump, outside air is automatically and directly introduced to the exhaust passage B side through this bypass passage D, thereby ensuring heat exchange. Therefore, as shown in Patent Document 1, it is not necessary to transfer part of the outside air introduced as supply air through the bypass passage A from the supply passage to the exhaust passage side, resulting in excellent operability.

[0031] For example, the specification in U.S. Patent Application Publication No. 2017 / 0356661 ( Figure 1As shown in 11), it is common knowledge for those skilled in the art to configure the heat exchanger on the exhaust side as a regeneration heat source at the regeneration (exhaust side) inlet side of the dehumidification rotor to improve the dehumidification performance of the dehumidification rotor by increasing the regeneration inlet temperature. However, in this invention, based on a concept different from this common knowledge, the heat exchanger 14 on the exhaust side is configured on the outlet side of the dehumidification rotor 6 on the exhaust B side, intentionally eliminating the need for a regeneration heat source for the dehumidification rotor 6. Therefore, the heat balance of the heat pump can be adjusted by the amount of outside air introduced from the bypass passage D, prioritizing the improvement of the cooling effect of the heat exchanger 5 on the supply side during summer.

[0032] (humidifier)

[0033] In the external air conditioning unit 23 described in Patent Document 1, the humidifier 11 is configured to be placed on the exhaust side for humidification in excessively dry indoor conditions such as winter. However, the humidification effect is improved when the supply air SA is humidified directly. Therefore, in this embodiment, the humidifier 11, such as a drip-type permeation humidifier or a two-fluid humidifier, is positioned on the outlet side of the dehumidification impeller 6 on the supply air side. Furthermore, in the comparative example described later, the external air conditioning unit 23 of Patent Document 1 is also configured such as... Figure 4 The case shown is where the humidifier 11 is installed on the air supply side instead of the exhaust side.

[0034] (Blower)

[0035] In the external air conditioning unit 23 described in Patent Document 1, since the air supply fan 8 is located at the outlet side of the dehumidification impeller 6, the air supply side becomes negatively pressured, creating an overall pressure balance that easily leads to leakage from the exhaust side to the air supply side. In particular, leakage on the indoor side of the dehumidification impeller 6, i.e., return air RA from the indoor exhaust path, easily leaks into the supply air SA of the air supply path. Therefore, even if ion exchange resin is used as the adsorption material for the dehumidification impeller 6, there is a concern that odors may transfer from the return air RA from the indoor exhaust path to the supply air SA. Therefore, in this invention, the air supply fan 8 is positioned at the outlet side of the total heat exchange impeller 3 and the inlet side of the dehumidification impeller 6 in the air supply path C, i.e., between the total heat exchange impeller 3 and the dehumidification impeller 6. This creates an overall pressure balance that easily leads to leakage from the air supply path C side to the exhaust path B side, effectively reducing the transfer of odors from the return air RA to the supply air SA. In addition, in case of concerns about odor leakage from the exhaust path B side, it is preferable to set up a purge fan area between the regeneration zone (exhaust path B side) and the treatment zone (air supply path C side) of the dehumidification rotor 6.

[0036] The exhaust-side blowers 13 are all located in front of the heat exchanger 14 on the exhaust-side of Patent Document 1 and the present invention. In Patent Document 1, they are located on the outlet side of the exhaust-side of the total heat exchange rotor 3, while in the present invention, they are located on the outlet side of the exhaust-side of the dehumidification rotor 6. In the present invention, the pressure loss caused by the bypass of the guide path (B', described later) for airflow from the outlet side of the total heat exchange rotor 3 to the inlet side of the dehumidification rotor 6 in the exhaust-side has a significant impact on the power consumption of the exhaust-side blowers 13. However, in the dehumidification rotor 6, by arranging the exhaust-side blowers 13 on the outlet side of the regeneration (exhaust-side B), a pressure balance is formed between the supply air SA from the supply air C side and the return air RA from the exhaust-side B, which has the effect of reducing odor transfer. Furthermore, by placing the blower 8 on the gas supply side between the total heat exchange rotor 3 and the dehumidification rotor 6, the temperature rises slightly after passing through the blower 8, but as will be described later, it can be divided into two rotor units and a heat pump / blower unit.

[0037] (Unit structure of external control unit)

[0038] As described above, the external control unit of the present invention comprises a total heat exchange impeller 3, a dehumidification impeller 6, a heat exchanger 5 on the supply side constituting the heat pump circuit, a heat exchanger 14 on the exhaust side, a compressor 16, a humidifier 11, a blower 8 on the supply side, a blower 13 on the exhaust side, and air filters 2, 10, and 28. Through these device structures, such as... Figure 3 As shown, it is divided into three units: a total heat exchanger unit 31, a heat pump / fan unit 32, and a dehumidification rotor unit 33.

[0039] Figure 3 (a) Figure 3 (b) shows the unit structure of the external control unit of the present invention and the structure of the equipment in each unit. Arrows are used in the reference to indicate the direction of air flow. Figure 3 (a) represents the case where the connected units are treated as a single unit. Figure 3 (b) shows an example set up for dividing units. Figure 3(c) shows the appearance of each segmented unit. The total heat exchanger unit 31 includes a total heat exchange impeller 3, air filters 2 and 10, and a bypass passage E and airflow adjustment device 26 at the lower part of the total heat exchange impeller 3. It is equipped with an external air inlet 35 for the air supply path C and a return air inlet 36 for the exhaust path B. The heat pump / fan unit 32 includes a fan 8 on the air supply side, a fan 13 on the exhaust side, a heat exchanger 5 on the air supply side constituting the heat pump circuit, a heat exchanger 14 on the exhaust side, and a compressor 16. It is equipped with an external air inlet 38 for the exhaust port 37 and the bypass passage D, and has a built-in airflow adjustment device 25. The dehumidifier impeller unit 33 includes a dehumidifier impeller 6 and an air filter 28. The dehumidifier impeller 6 has a bypass passage F and an airflow adjustment device 27 at the lower part, and an air supply port 39 for the indoor space.

[0040] Depending on the layout settings, such as Figure 3 As shown in (a), the individual units can be connected to form a single unit, or as... Figure 3 As shown in (b), the unit is divided into sections and connected to each other by ductwork. This divided unit structure allows for selection of a configuration method that matches the installation location, offering flexibility and excellent transportability and installation ease. It can also be configured in situations where space is limited, such as when upgrading existing equipment to the external control unit of this invention. By making the heat pump circuit a unit-integrated type, on-site construction of refrigerant piping or wiring is eliminated, thus shortening the construction period. Furthermore, the external control unit of this invention has a symmetrical design, enabling reverse configurations (left and right), thereby shortening the delivery time.

[0041] like Figure 3 As shown in (a), the return air RA flowing from the total heat exchange rotor 3 in the exhaust path B is introduced into the dehumidification rotor 6 (introduction path B') through the upper part of the unit. By mounting the introduction path B' inside the unit, the overall height of the device increases, but the ductwork construction at the customer's site can be reduced. The introduction path B' can also be made detachable, and depending on the installation environment, it can be switched to a ductwork mode by replacing it with a sandwich panel equipped with a duct flange. Similarly, by mounting the rotor bypass passages (bypass passages E and F) and airflow adjustment devices 26 and 27 on the air supply path C side inside the unit, the bypass ductwork construction at the customer's site can be reduced. Furthermore, the bypass passages E and F can also be made detachable, and depending on the installation environment, it can be switched to a ductwork mode by replacing it with a sandwich panel equipped with a duct flange. By also being able to separately install the humidifier unit 34, including the humidifier 11, within the unit, as an option, the humidifier unit 34 can be omitted or installed later according to the customer's requirements.

[0042] Furthermore, the modular structure or the constituent devices built into each unit are not limited to the above-described methods and can be appropriately modified as needed. For example, in Figure 3In this configuration, the exhaust path B is located at the top, and the air supply path C is located at the bottom, but they can also be arranged in reverse order. Furthermore, for example, the air supply fan 8 can be included in the total heat unit 31, or the exhaust fan 13 can be included in the dehumidification unit 33. The unit's division can also be further reduced, for example, by designing it as a unit consisting only of an air supply fan or a unit consisting only of a heat pump. Snow covers or similar devices can also be appropriately installed at the outlet or inlet.

[0043] Based on the above structure, the external air handling operation of the external air conditioning unit involved in this embodiment will be described as follows. In summer cooling and dehumidification operation (cooling mode), the heat exchanger 5 on the supply side is used as an evaporator to cool the external air, and the heat exchanger 14 on the exhaust side is used as a condenser. Additional dehumidification based on the dehumidification rotor 6 is also performed. During the transition season, the total heat exchange rotor 3 and the dehumidification rotor 6 are stopped, and external air is supplied through bypass passages E and F (air supply mode). In winter heating and humidification operation (heating mode), the heat exchanger 5 on the supply side is used as a condenser to heat the external air, and the heat exchanger 14 on the exhaust side is used as an evaporator. The dehumidification rotor 6 is stopped, and air is supplied to the indoor space through bypass passage F. Furthermore, humidification operation based on the humidifier 11 is performed as needed. In this way, by switching between three operating modes—cooling mode in summer, air supply mode in the transitional season, and heating mode in winter—using heat pump technology, the system detects the temperature and humidity of the outside air and automatically controls the air supply to meet the set conditions. Furthermore, by incorporating a total heat exchanger, it also recovers energy from the return air exhausted from the indoor space, which can suppress energy consumption and significantly reduce operating costs.

[0044] The external air conditioning unit of this invention can automatically switch between air supply / cooling / heating modes by controlling the ON / OFF state of the constituent devices according to the outside temperature and humidity. The ON / OFF states of each constituent device under these three modes are shown in Table 1. In Table 1, ON of the airflow adjustment devices 26 and 27 is represented as OPEN, and OFF as CLOSE. For example, the temperature and humidity of the outside air OA, supply air SA, and return air RA are measured by a temperature and humidity sensor (THS), and the constituent devices are controlled by a control device (not shown). The external air conditioning unit of this invention mainly adjusts the humidity of the supply air SA, and the temperature of the supply air SA is as close as possible to the customer's required specifications for the indoor space, but in a manner determined accordingly. Furthermore, the temperature adjustment of the indoor space is mainly performed by the internal air conditioning unit (latent heat and sensible heat separation). Thus, the indoor space is set, for example, to 24±1℃ and 50±5%RH (hereinafter, all temperatures are set in "Celsius"). The following are examples of operation and performance calculations for summer, transitional seasons, and winter, respectively, as Examples 1, 2, and 3.

[0045] [Table 1]

[0046] (Summer operation: Cooling mode)

[0047] The cooling and dehumidification operation in summer is explained. In the air supply circuit C, outdoor air OA is delivered to the total heat exchange rotor 3 via the air supply side fan 8, which acts as a handling fan, and passes through the air filter 2. In the total heat exchange rotor 3, the outdoor air OA undergoes total heat exchange with the return air RA from the indoor space, resulting in dehumidification and cooling. The outdoor air OA that has undergone total heat exchange is then delivered to the heat exchanger 5 on the air supply side, which acts as the evaporator in the heat pump circuit, and is further cooled. The air passing through the heat exchanger 5 on the air supply side is then delivered to the dehumidification rotor 6 for dehumidification and is supplied to the indoor space as air supply SA via the air filter 28.

[0048] In exhaust path B, return air RA from the indoor space is delivered to the total heat exchange impeller 3 via the exhaust-side supply fan 13, which acts as a regenerator fan, and passes through the air filter 10. The return air RA undergoes total heat exchange with the outside air OA in the total heat exchange impeller 3, resulting in humidification and heating. The returned air RA, after total heat exchange, is then delivered to the dehumidification impeller 6 for humidification and cooling. The air passing through the dehumidification impeller 6 is then delivered to the exhaust-side heat exchanger 14, which serves as the condenser in the heat pump circuit, and finally discharged outside the unit as exhaust air EA. In summer, the cooling load on the supply-side heat exchanger 5 increases; therefore, as needed, outside air is automatically introduced directly to the exhaust path B via the bypass passage D. The heat dissipation of the exhaust-side heat exchanger 14 is controlled by the temperature of the exhaust air EA, stabilizing the heat balance of the heat pump circuit. Furthermore, the humidifier 11 is stopped.

[0049] [Example 1]

[0050] The air conditions inside and outside the device of the external air conditioning unit of the present invention during summer are shown. Figure 5 . Figure 5 Table (1) to (9) represent Figure 2 The air conditions at positions (1) to (9) inside and outside the device. Hereinafter, in Examples 2 to 3 and Comparative Examples 1 to 3 ( Figure 4 The same applies in Examples 1-3 and Comparative Examples 1-3. Furthermore, in Examples 1-3 and Comparative Examples 1-3, the airflow rate of the gas supply SA was set to 5000 m³ / s. 3 / h, Set the return air RA airflow to 4000m³ / h 3 / h was used for trial calculation.

[0051] The process of the comparative example described later ( Figure 4 ) and a comparative example 1 for summer ( Figure 5The following comparisons were made. In the comparative example, the return air RA from the room was introduced into the dehumidification rotor 6, but in the external air conditioning unit of the present invention, it was introduced into the total heat exchange rotor 3. As a result, the total heat exchange effect between the outside air OA and the return air RA in the total heat exchange rotor 3 is improved, and compared with the comparative example 1, it has the effect of increasing the temperature of the air at the regeneration (exhaust path B side) inlet side of the dehumidification rotor 6. The higher the regeneration temperature of the dehumidification rotor, the greater the relative humidity difference, and therefore the better the dehumidification performance. The temperature at the regeneration inlet side of the dehumidification rotor 6 was 32.1°C in Example 1 and 26.0°C in Comparative Example 1. The higher regeneration inlet temperature in Example 1 allows for effective utilization of the total heat exchange effect of the high-temperature outside air OA in summer. Therefore, the dehumidification amount (the difference in absolute humidity between air (3) and air (5)) was 1.7 g / kg (DA) in Example 1, compared to 0.8 g / kg (DA) in Comparative Example 1.

[0052] The indoor temperature is adjusted to the target temperature required by the installed air conditioning or other indoor control unit. The temperature of the gas supply SA is 26.4°C in Example 1, compared to 20.5°C in Comparative Example 1, which is lower than the target temperature, increasing the temperature adjustment load on the indoor control unit.

[0053] (Operation during the transition season: air supply mode)

[0054] The operation of the air supply system during the transition season is explained. Only air supply fans 8 and 13 are operated, and airflow adjustment devices 26 and 27 are set to the OPEN state, stopping other components. Specifically, the heat exchanger 5 on the supply side, the heat exchanger 14 on the exhaust side, the compressor 16, and the humidifier 11, which constitute the heat pump circuit, are stopped. Therefore, the power consumption in air supply mode is solely for the power of the air supply fans. Furthermore, the total heat exchange impeller 3 and the dehumidification impeller 6 are stopped, and on the supply side of air supply line C, outside air OA is supplied to the room via their respective impeller bypass passages E and F. Airflow adjustment devices 26 and 27 are installed on bypass passages E and F respectively, allowing adjustment of the airflow in air supply line C. By allowing the airflow to pass through bypass passages E and F, the pressure loss is lower compared to passing through the impeller, thus suppressing the power consumption of the air supply fan 8 on the supply side.

[0055] [Example 2]

[0056] The air conditions inside and outside the device of the external air conditioning unit of the present invention during the transitional season are shown in the figure. Figure 5 Since it only operates for air supply, the air temperature rises by about 1°C after passing through blowers 8 and 13. Compared with Comparative Example 2 described later, the performance remains the same, but in Example 2, by bypassing the impeller on the air supply path C side for air supply, the pressure loss is reduced, thus suppressing the power consumption of blower 8 on the air supply path side.

[0057] (Winter operation: Heating mode)

[0058] The operation of heating and humidification in winter is explained. In winter, the dehumidification impeller 6 is stopped, and air is introduced into the bypass passage F from the air supply line C side. The airflow of the air supply SA is adjusted by the airflow adjustment device 27. In the air supply line C, outside air OA is delivered to the total heat exchange impeller 3 via the air supply fan 8, which acts as a handling fan, and passes through the air filter 2. Outside air OA undergoes total heat exchange with return air RA from the indoor space in the total heat exchange impeller 3. The outside air OA that has undergone total heat exchange is then delivered to the heat exchanger 5, which acts as the condenser in the heat pump circuit, and is heated. The air that has passed through the heat exchanger 5 on the air supply line side passes through the bypass passage F of the dehumidification impeller 6 and is supplied to the indoor space as air supply SA. Furthermore, if the air in the indoor space is excessively dry, the humidity is adjusted by humidifying the air supply SA using the humidifier 11.

[0059] In exhaust path B, return air RA from the indoor space is delivered to the total heat exchange rotor 3 via the exhaust side fan 13, which acts as a regenerator fan, and passes through the air filter 10. The return air RA undergoes total heat exchange with the outside air OA in the total heat exchange rotor 3, resulting in cooling and dehumidification. After total heat exchange, the return air RA is then delivered to the exhaust side heat exchanger 14, which acts as the evaporator in the heat pump circuit, via the stopped dehumidification rotor 6, and finally discharged outside the unit as exhaust air EA.

[0060] [Example 3]

[0061] The air conditions inside and outside the device of the external air conditioning unit of the present invention during winter are shown. Figure 5In Comparative Example 3, described later, both the total heat exchange rotor 3 and the dehumidification rotor 6 are operated. As shown in Comparative Example 3, those skilled in the art would prefer to heat the air using the heat exchanger 5 on the air supply side and pass it through the dehumidification rotor 6 to achieve a humidification effect. However, in this invention, the dehumidification rotor 6 is stopped and bypassed. Furthermore, since the return air RA from the room undergoes total heat exchange with the outside air OA in the total heat exchange rotor 3, the outside air can be sufficiently humidified using only the total heat exchange rotor 3. Therefore, the air supply SA passes through the bypass passage F that bypasses the dehumidification rotor 6, thereby reducing pressure loss and reducing the power consumption of the air supply fan 8 on the air supply side. On the other hand, the heat exchanger 5 on the air supply side heats the air containing humidity, thus increasing energy consumption compared to Comparative Example 3. The humidification amount of the outside air OA before humidifier 11 (the difference in absolute humidity between air (4) and air (1)) was 4.8 g / kg (DA) in Example 3 when humidified only by the total heat exchange wheel 3, and 5.3 g / kg (DA) in Comparative Example 3 when humidified by both the total heat exchange wheel 3 and the dehumidification wheel 6 (2.2 g / kg (DA) when humidified by the total heat exchange wheel 3 and 3.1 g / kg (DA) when humidified by the dehumidification wheel 6). The humidification amount of Example 3 is less than that of Comparative Example 3, but sufficient humidification effect can be obtained by using only the total heat exchange wheel 3. In Patent Document 1, although it is said that a regenerated heat source is not required, in winter, the heat exchanger 5 on the gas supply side is used as a condenser to heat the air, thereby obtaining the humidification effect of the dehumidification wheel 6. However, in this invention, the heat exchanger 5 on the gas supply side is used as a condenser to heat the air, but in terms of supplying air by bypassing the dehumidifying impeller 6, the regeneration heat source of the dehumidifying impeller 6 is not actually needed.

[0062] In Example 3, without humidifier 11 or without humidification, air passing through the heat exchanger 5 on the air supply side is directly supplied to the indoor space as air supply SA via bypass F. Therefore, air supply can be maintained while preserving the heating effect in the heat exchanger 5 on the air supply side, which acts as a condenser. On the other hand, in Comparative Example 3, humidification is performed using a dehumidifying impeller. Therefore, although humidification is achieved, the temperature decreases. Alternatively, without humidification, since the temperature of the air supply SA does not decrease due to humidifier 11, it is sufficient to keep the temperature rise of the heat exchanger 5 on the air supply side close to the required indoor conditions, thereby suppressing energy consumption.

[0063] The operation of the external air conditioning unit of the present invention in summer, transitional seasons, and winter is as described above. Furthermore, it is set to cooling mode in summer, air supply mode in transitional seasons, and heating mode in winter, but automatically switches operating modes according to the temperature and humidity conditions of the outside air. For example, even in transitional seasons, when the temperature and humidity of the outside air deviate from the set temperature and humidity range for the supplied air, it may sometimes switch from air supply mode to cooling mode or heating mode.

[0064] [Example 4]

[0065] Making with Figure 2 The experimental machine illustrating the process and device structure of the external control unit of the present invention was tested, and experiments were conducted in the transitional season air supply mode and the winter heating mode. The specifications of the experimental machine were set at 5000m. 3 / h, the diameters of both the total heat exchange rotor 3 and the dehumidification rotor 6 are set to Φ1100mm. The test results are shown in Figure 6 .

[0066] Figure 6 Figure (a) shows the test results of switching operation control from heating mode to ventilation mode. The set temperature of the air supply SA in ventilation mode was set to 20–26°C, and the set dew point was set to 7.5–13.5°C DP. The temperature and humidity of the outside air were detected, and as the outside air temperature rose, the system automatically switched from heating mode to ventilation mode, demonstrating a smooth transition. The air supply SA was supplied within the set temperature, humidity, and dew point conditions.

[0067] Figure 6 (b) indicates that in relation to Figure 6 (a) Results of continuous operation in heating mode on different winter days. The set temperature of the gas supply SA in heating mode is set to 28°C. The gas supply SA remains almost constant around 28°C relative to changes in the outside air temperature. This shows that the gas supply can absorb changes in the outside air and achieve a stable supply relative to the set temperature.

[0068] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the above embodiments. Various modifications or variations can be made within the scope of the present invention described in the technical solution, and such modifications or variations are also included within the scope of the present invention. For example, after the bypasses branching to the respective bypasses E and F, an airflow adjustment device may also be added to the inlet side of each impeller of the air supply line C to adjust the airflow through each impeller. If the airflow adjustment devices 26 and 27 are set to the OPEN state, air flows into the bypasses E and F with low pressure loss. Therefore, as shown in this embodiment, the airflow adjustment device may not be provided at the inlet side of each impeller, thereby reducing costs. Both bypasses E and F may be provided, or only one of them may be provided. Furthermore, the order of the air filter 28 and the humidifier 11 may be changed. Moreover, the total heat exchanger has been described as a rotating total heat exchange impeller, but it may also be replaced by a stationary total heat exchange impeller. Furthermore, it may not be limited to temperature and humidity, but may be controlled and managed by dew point to meet customer requirements or supply conditions of the air supply SA.

[0069] The external air conditioning unit of this invention can be controlled by a single heat pump circuit or by multiple circuits or equipment structures. In cooling or heating mode, when the set conditions are close to those of the air supply mode, the load on the heat pump circuit decreases (in air supply mode, the heat pump circuit is OFF). Controlling the heat pump circuit under this low load is a challenge. Therefore, in this invention, the heat pump circuit is divided into two systems: one as the base system and the other as the adjustment system. The compressor is frequency-controlled, and the heat pump circuits of these two systems are connected in series or parallel. When the outside air load is low and the heat pump circuit is under low load, the base system is stopped, and only the adjustment system operates. Furthermore, fine humidity adjustments can be made by using hot air bypass according to the load conditions. On the other hand, when the outside air load is high in cooling / heating mode, the compressor of the base system is started when the capacity of the adjustment system cycle is overloaded, utilizing the heat pump circuits of both systems. Furthermore, under high external gas load conditions, the enthalpy difference between the external gas and the set gas supply conditions can be calculated, and the number of operating compressors in the basic system can be determined based on the load magnitude (in the case of multiple compressors). In addition, not limited to the heat pump circuits of the basic system and the adjustment system, by modularization and control by multiple constituent devices or heat pump circuits, the overall efficiency of the heat pump circuit system can be improved, a backup system can be built, and the service life can be extended.

[0070] When the external control unit of this invention is set to a high-volume type, such as Figure 7 As shown in (a), the heat pump circuit can be equipped with multiple heat exchangers 5, 14 or compressor 16 as condensers and / or evaporators, or as follows: Figure 7As shown in (b), multiple refrigerant circuits (heat pump circuits) are maintained. For example, in Figure 7 When the heat exchanger 5 on the gas supply side is set as an evaporator and the heat exchanger 14 on the exhaust side is set as a condenser, in Figure 7 In (a), multiple evaporators 5 (5a, 5b, 5c) are connected in parallel, and similarly, multiple condensers 14 (14a, 14b, 14c) and compressors 16 (16a, 16b, 16c, 16d) are also connected in parallel (parallel circuit not shown), thus forming a heat pump circuit. Figure 7 In (b), one evaporator 5 (5a, 5b, 5c), one condenser 14 (14a, 14b, 14c), and one compressor 16 (16a, 16b, 16c) are each installed in one heat pump circuit, maintaining multiple heat pump circuits. However, this is not a limitation; one or more evaporators, condensers, and compressors can be installed in a single heat pump circuit and connected in parallel or series, etc., with appropriate modifications.

[0071] (Comparative example)

[0072] Figure 4 The external adjustment machine shown in Patent Document 1 is shown in the figure. Figure 1 In the case where the humidifier 11 is located on the air supply side instead of the exhaust side, the following will be compared with the external control unit of the present invention. Figure 2 While comparing Examples 1 to 3, operational and performance calculation examples for summer, transitional season, and winter are respectively described as Comparative Examples 1, 2, and 3. The air conditions inside and outside the external control unit of Comparative Examples 1 to 3 are shown below. Figure 5 Furthermore, Table 2 shows the ON / OFF status of each component device under the three modes of the comparative example: summer cooling mode, transitional season air supply mode, and winter heating mode.

[0073] [Table 2]

[0074] [Comparative Example 1]

[0075] During summer cooling and dehumidification operation (cooling mode), outdoor air OA is delivered to the total heat exchange rotor 3 via the air filter 2 through the supply fan 8, which acts as a handling fan. In the total heat exchange rotor 3, it undergoes total heat exchange with the return air RA from the indoor space via the dehumidification rotor 6. The outdoor air OA that has undergone total heat exchange is then delivered to the heat exchanger 5 on the supply side of the evaporator, which acts as a heat pump circuit, and is cooled. The air passing through the supply side heat exchanger 5 is then delivered to the dehumidification rotor 6 for dehumidification and supplied to the indoor space as supply air SA. The return air RA from the indoor space is delivered to the dehumidification rotor 6 via the supply fan 13, which acts as a regeneration fan, and is humidified and cooled. The return air RA passing through the dehumidification rotor 6 is then delivered to the total heat exchange rotor 3 for total heat exchange with the outdoor air OA. The air passing through the total heat exchange rotor 3 is then delivered to the heat exchanger 14 on the exhaust side of the condenser, which acts as a heat pump circuit, and is discharged outside the unit as exhaust air EA. In summer, to ensure the heat pump's heat dissipation, for example, one-third of the outside air OA introduced into the supply air line is introduced into the bypass air line A.

[0076] [Comparative Example 2]

[0077] During the transitional season's air supply operation (air supply mode), only air supply fans 8 and 13 are operated, while other components are shut down. Therefore, the only power consumption is for the air supply fans. Outside air OA passes sequentially through the total heat exchange rotor 3 and dehumidification rotor 6 in the air supply circuit, and is supplied to the indoor space as supply air SA. Return air RA from the indoor space passes sequentially through the dehumidification rotor 6 and total heat exchange rotor 3 in the exhaust circuit, and is discharged as exhaust air EA.

[0078] [Comparative Example 3]

[0079] During winter heating and humidification operation (heating mode), outdoor air OA is delivered to the total heat exchange rotor 3 via the air filter 2 through the supply fan 8, which acts as a handling fan. In the total heat exchange rotor 3, it undergoes total heat exchange with the return air RA from the indoor space via the dehumidification rotor 6. The outdoor air OA that has undergone total heat exchange is then delivered to the heat exchanger 5 on the supply side of the condenser, which acts as a heat pump circuit, and is heated. The air passing through the heat exchanger 5 on the supply side is delivered to the dehumidification rotor 6 for humidification and supplied to the indoor space as supply air SA. Additionally, if the air in the indoor space is excessively dry, the humidity of the supply air SA is increased by humidifying it using the humidifier 11. The return air RA from the indoor space is delivered to the dehumidification rotor 6 via the supply fan 13, which acts as a regeneration fan, and is dehumidified. The return air RA passing through the dehumidification rotor 6 is then delivered to the total heat exchange rotor 3 for total heat exchange with the outdoor air OA. After passing through the total heat exchange wheel 3, the air is delivered to the heat exchanger 14 on the exhaust side of the evaporator, which serves as the heat pump circuit, and then discharged outside the device as exhaust EA.

[0080] according to Figure 5 In both the external control unit of the present invention (Examples 1-4) and the conventional external control units (Comparative Examples 1-3) described in Patent Document 1, the COP (Coefficient of Performance) is the same. On the other hand, regarding power consumption, especially in summer and transitional seasons, the external control unit of the present invention consumes less power, thus saving energy. Therefore, the energy efficiency of the external control unit of the present invention is improved, and a compact, modular structure is achieved through improvements in the equipment structure. The installation area is reduced by 10% compared to the external control unit of Patent Document 1.

[0081] Industrial availability

[0082] The air conditioner of this invention can be used not only for general air conditioning purposes such as commercial facilities, hotels, and office buildings, but also for factories that require year-round air conditioning management and have production processes or environments that require the introduction of external air, such as food processing, pharmaceutical manufacturing, and the automotive industry.

[0083] Products used as external control units include AHUs (Air Handling Units) or FCUs (Fan Coil Units), AHUs (Total Heat Exchangers) equipped with total heat exchangers, general-purpose dehumidifying rotors, and, as in this invention, two-rotor dehumidifying rotors. Furthermore, as heat sources, there are chilled / hot water systems and heat pumps. However, the energy efficiency of general external control units is poor, accounting for approximately 30% of annual operating costs. While some external control units offer improved performance, truly groundbreaking energy-saving devices remain scarce, limiting the range of options available.

[0084] The external control unit of this invention uses a total heat exchanger, a dehumidifying impeller and a heat pump, therefore, compared with other external control units, the initial cost or CAPEX (capital expenditure) is higher and the size of the unit is also more likely to increase.

[0085] However, operating costs, or OPEX (Operating Expenditure), including the cost of electricity or other chilled water or steam, can be significantly reduced, reaching the lowest among external control units. For example, under the same conditions, calculations show that compared to an AHU using chilled water and steam as a heat source, the CAPEX is 1.88 times higher, but the OPEX is only 0.32 times higher. Calculations show that the cost-effectiveness of the external control unit of this invention reverses after 3 years of initial use, and the longer the usage time, the higher the cost-effectiveness. Furthermore, compared to a 2-rotor dehumidifier with the same device structure (total heat exchanger + dehumidifier rotor + heat pump), the device itself has lower costs, achieving energy savings and space conservation. This is because while the process of the external control unit of this invention is complex, the equipment is simplified by designing the unit as a modular unit and assembling all constituent equipment within the unit. Moreover, the carbon dioxide production of the external control unit of this invention is the lowest among various external control units, remaining at 0.41 times that of an AHU using chilled water and steam as a heat source. The air conditioner of this invention is electrically driven using a heat pump, and therefore, when combined with clean electricity, it can contribute to climate neutrality. Thus, the air conditioner of this invention possesses particularly superior energy efficiency and environmental contribution among various air conditioners, enabling the provision of a device that meets the societal needs of a future decarbonized society.

[0086] Symbol Explanation

[0087] 1, 12, 15, 25, 26, 27 - Airflow adjustment device; 2, 10, 28 - Air filter; 3 - Total heat exchanger impeller; 4, 7 - Gear motor; 5 - Heat exchanger on the air supply side; 6 - Dehumidifier impeller; 8 - Air supply side blower; 9 - Indoor space; 11 - Humidifier; 13 - Exhaust side blower; 14 - Exhaust side heat exchanger; 16 - Compressor; 17, 18, 19 - Temperature sensor; 20 - Dew point sensor. 21-Sensor, 22-Temperature regulator, 23-Dew point control device, 31-External air conditioning unit, 32-Heat pump / fan unit, 33-Dehumidifier rotor unit, 34-Humidifier unit, 35-Outdoor air inlet to the air supply path, 36-Return air inlet to the exhaust path, 37-Exhaust port, 38-Outdoor air inlet to bypass path D, 39-Air supply port to the indoor space, A, D, E, F-Bypass path, B-Exhaust path, B'-Inlet path, C-Air supply path.

Claims

1. An external air handling air conditioner, characterized in that, The device has an exhaust duct that discharges return air from an indoor space to the outside and an air supply duct that supplies outside air to the indoor space. A total heat exchanger is arranged at the front end of the air supply duct in the order in which the outside air passes through, and a dehumidifying impeller is arranged at the rear end. The total heat exchanger and the dehumidifying impeller span the exhaust duct and the air supply duct. In the total heat exchanger, total heat exchange occurs between the return air from the indoor space and the outside air. In the dehumidifying impeller, latent heat exchange occurs between the return air that has undergone total heat exchange and the outside air. In the air supply duct, a blower is arranged between the total heat exchanger and the dehumidifying impeller on the air supply duct side.

2. The external air handling air conditioner according to claim 1, characterized in that, The total heat exchanger is a total heat exchange rotor.

3. The external air handling air conditioner according to claim 1, characterized in that, The total heat exchanger and / or dehumidifying impeller contain ion exchange resin as an adsorption material.

4. The external air handling air conditioner according to claim 1, characterized in that, A heat exchanger for the gas supply side is provided at the outlet side of the total heat exchanger and the inlet side of the dehumidifying impeller on the gas supply side, and a heat exchanger for the exhaust side is provided at the outlet side of the dehumidifying impeller on the exhaust side. The configuration includes the heat exchanger for the gas supply side, the heat exchanger for the exhaust side, and a heat pump circuit with a compressor. The heat pump circuit performs heat exchange between the outside air passing through the gas supply side of the total heat exchanger and the exhaust gas passing through the exhaust side of the dehumidifying impeller.

5. The external air handling air conditioner according to any one of claims 1 to 4, characterized in that, The dehumidification impeller is a passive dehumidification impeller that does not require a regeneration heat source.

6. The external air handling air conditioner according to any one of claims 1 to 4, characterized in that, In the exhaust path, a bypass passage for directly introducing outside air is provided at the outlet side of the dehumidifying impeller and in front of the heat exchanger on the exhaust path side.

7. The external air handling air conditioner according to any one of claims 1 to 4, characterized in that, In the gas supply circuit, in the total heat exchanger and / or the dehumidification impeller, a bypass passage is provided to bypass the inlet side and the outlet side, respectively.

8. The external air handling air conditioner according to claim 4, characterized in that, It has three operating modes: cooling mode, air supply mode, and heating mode. It automatically switches the operating mode according to the temperature and humidity of the outside air to achieve the set air supply conditions. In cooling mode, the heat exchanger on the air supply side is used as an evaporator and the heat exchanger on the exhaust side is used as a condenser. In heating mode, the heat exchanger on the air supply side is used as a condenser and the heat exchanger on the exhaust side is used as an evaporator.

9. The external air handling air conditioner according to claim 4, characterized in that, It is divided into three units: a total heat exchanger unit, including the total heat exchanger; a heat pump / fan unit, including the heat exchanger on the gas supply side, the heat exchanger on the exhaust side, the compressor, and the fan on the gas supply side that constitute the heat pump circuit; and a dehumidifying impeller unit, including the dehumidifying impeller.

10. The external air handling air conditioner according to any one of claims 1 to 4 and 9, characterized in that, In the air supply circuit, a humidifier or humidifier unit is also provided on the outlet side of the dehumidification rotor.

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