Design method for residential ventilation systems and residential ventilation methods

Abstract

This document provides a method for designing residential ventilation systems that enable proper ventilation. [Solution] The method for designing the ventilation system 21 of a house H includes the steps of: determining the required ventilation rate V per unit time of the house H; determining the effective ventilation rate R defined by a specific formula; determining the standard airflow rate, which is the airflow rate per unit time required for the fan 22, by dividing the required ventilation rate V by the effective ventilation rate R; and selecting a fan 22 that has power capable of supplying air to the underfloor space 5 at an airflow rate equal to or greater than the standard airflow rate.

Description

[Technical Field]

[0001] The present invention relates to a method for designing a residential ventilation system and a method for ventilating a residential building. [Background technology]

[0002] Patent Document 1 below describes a ventilation system for a house. In this ventilation system, outside air supplied from an outside air intake in the underfloor space is heat-exchanged with geothermal heat. The air in the underfloor space, including the heat-exchanged outside air, is then supplied to the above-floor space by an air supply means. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2015-187509 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] Generally, residential floors are designed to be airtight, but inevitably, gaps exist that allow air to pass into the space beneath the floor. Therefore, when the amount of air entering the space beneath the floor increases, the proportion of outside air in the ventilation air decreases, leaving room for further improvement in ensuring proper ventilation.

[0005] This invention was devised in view of the above-described circumstances, and its main objective is to provide a method for designing a residential ventilation system that enables proper ventilation. [Means for solving the problem]

[0006] The present invention is a design method for a residential ventilation system, wherein the house comprises an insulated foundation, a first floor, an underfloor space defined by the foundation and the first floor, an above-floor space provided above the underfloor space via the first floor, and a foundation air inlet provided in the foundation for introducing outside air into the underfloor space; the ventilation system comprises a fan for supplying air in the underfloor space, including the outside air introduced from the foundation air inlet, to the above-floor space; and the design method comprises: a step of obtaining a required ventilation volume V per unit time of the house; a step of obtaining an effective ventilation rate R defined by the following formula; a step of dividing the required ventilation volume V by the effective ventilation rate R to obtain a reference air volume, which is the air volume per unit time required for the fan; and a step of selecting the fan having power capable of supplying air in the underfloor space at an air volume equal to or greater than the reference air volume. R=A / (A+B) B=C×D Wherein: R: effective ventilation rate A: opening area of the foundation air inlet (cm 2 ) B: equivalent gap area of the first floor (cm 2 ) C: gap volume per unit area of the first floor (cm 2 / m 2 ) D: total area of the first floor (m 2 ) Effects of the Invention

[0007] By employing the above steps, the design method for a residential ventilation system of the present invention makes it possible to design a ventilation system capable of achieving proper ventilation. Brief Description of the Drawings

[0008] [Figure 1] 1 is a perspective view showing an example of a computer for carrying out the design method for a residential ventilation system. [Figure 2] 2 is a conceptual diagram showing an example of a house provided with a ventilation system. [Figure 3] This is a conceptual diagram showing an example of the configuration of a control device. [Figure 4] This flowchart shows an example of the processing steps for designing a residential ventilation system. [Figure 5] A flowchart illustrating an example of a ventilation procedure for a house. [Figure 6] This figure shows an example of a house with the air conditioning running. [Figure 7] This is a flowchart illustrating the processing procedure for a residential ventilation method according to another embodiment of the present invention. [Figure 8] This flowchart shows an example of the processing procedure for the operation step of another embodiment of the present invention. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described below with reference to the drawings. It should be understood that the drawings contain exaggerations and representations that differ from the actual dimensional ratios of the structures in order to aid in understanding the content of the invention. Furthermore, the same or common elements are denoted by the same reference numerals throughout each embodiment, and redundant explanations are omitted. Moreover, the specific configurations shown in the embodiments and drawings are for the purpose of understanding the content of the present invention, and the present invention is not limited to the specific configurations shown in the drawings.

[0010] In this embodiment, a ventilation system to be installed in a house H is designed using the design method for a residential ventilation system (hereinafter sometimes referred to as the "design method"). Computer 1 is used in the design method of this embodiment.

[0011] Figure 1 is a perspective view showing an example of a computer 1 for executing a design method for a residential ventilation system. The computer 1 in this embodiment consists of a main unit 1a, a keyboard 1b, a mouse 1c, and a display device 1d. The main unit 1a is provided with, for example, a processing unit (CPU), ROM, working memory, a storage device such as a magnetic disk, and disk drive devices 1a1 and 1a2. Software for executing the design method of this embodiment is pre-stored in the storage device. Note that the computer 1 is not limited to this form, and may be configured as, for example, a portable information terminal (tablet type, etc.) or a server (cloud server), etc.

[0012] [Housing] Figure 2 is a conceptual diagram showing an example of a house H equipped with a ventilation system 21. In this embodiment, the house H is exemplified as a single-story building, but it may be two stories or more. Also, in this embodiment, the house H is configured as an industrialized house, but it is not particularly limited.

[0013] The house H of this embodiment includes a foundation 3, a first-floor floor 4, an underfloor space 5, an upper floor space 6, and a foundation air intake 7.

[0014] [Basics] The foundation 3 in this embodiment is constructed as a reinforced concrete strip foundation, but is not particularly limited and may be a raft foundation, for example. The foundation 3 is composed of a base portion 3a that extends horizontally underground and a rising portion 3b that extends upward from approximately the center in the width direction of the base portion 3a and protrudes from the ground 8. The foundation 3 in this embodiment includes an outer foundation 3A arranged around the perimeter of the house H and an inner foundation 3B arranged inside the house H. An access opening 10 is also formed in the inner foundation 3B.

[0015] The foundation 3 of this embodiment is insulated. Therefore, the house H of this embodiment is configured as a foundation-insulated house. In this embodiment, insulation material 11 is provided on the outer foundation 3A, but not on the inner foundation 3B. As the insulation material 11, for example, polystyrene foam or the like can be appropriately used.

[0016] [First floor flooring] The first-floor floor (hereinafter sometimes referred to as "floor") 4 of this embodiment extends horizontally between the rising sections 3b, 3b of the foundation 3. The floor 4 of this embodiment is, for example, constructed as flooring made up of multiple plank panels, but is not particularly limited.

[0017] [Underfloor space] The underfloor space 5 is separated by the foundation 3 and the first-floor floor 4. Outside air Ao is introduced into this underfloor space 5 through the foundation air intake 7. Therefore, the air Au in the underfloor space 5 (hereinafter sometimes referred to as "underfloor air") contains outside air Ao.

[0018] The underfloor air Au (outside air Ao) exchanges heat with geothermal energy, which has little temperature fluctuation throughout the year, via the ground (concrete slab) 8. As a result, the underfloor space 5 stores underfloor air Au that is cooler in summer and warmer in winter compared to outside air Ao.

[0019] In this embodiment, the underfloor space 5 is divided into multiple spaces 5a and 5b by the inner foundation 3B. In this embodiment, the multiple spaces 5a and 5b can be accessed by underfloor air Au through the access opening 10.

[0020] [Floor space] The above-floor space 6 is located above the under-floor space 5 via the floor 4 of the first floor. In this embodiment, the above-floor space 6 is partitioned by the floor 4, ceiling 12, exterior wall 13, and partition wall 14, and includes a living room 15 and a non-living room 16 such as a toilet. In this embodiment, air can be exchanged between the living room 15 and the non-living room 16.

[0021] An air conditioner 17 capable of cooling operation may be provided in the floor space 6. By operating such an air conditioner 17 for cooling during the summer, it is possible to lower the room temperature in the floor space 6 and improve comfort. The air conditioner 17 may also be capable of heating operation. The operation of the air conditioner 17 may be controlled, for example, by a control device 25.

[0022] [Basic air supply port] The foundation air intake vent 7 is provided in the foundation 3 (outer foundation 3A) and is provided to introduce outside air Ao into the underfloor space 5. In this embodiment, the foundation air intake vent 7 is configured as a hole that penetrates the rising portion 3b of the foundation 3 and the insulation material 11 between the outdoors 18 and the underfloor space 5, but is not particularly limited. In this embodiment, only one foundation air intake vent 7 is provided to reduce the influence of wind pressure, but is not particularly limited. For example, multiple foundation air intake vents 7 may be provided depending on the size of the house H, etc. In this case, multiple foundation air intake vents 7 may be provided on the same side of the foundation 3.

[0023] In this embodiment, the foundation air intake vent 7 penetrates from the outdoor side 18 (the outer surface of the outer foundation 3A) to the underfloor space 5 (the inner surface of the insulation material 11) with the same opening area (cross-sectional area). This allows outside air Ao to be smoothly supplied to the underfloor space 5. Here, "same" dimensions etc. means that minor manufacturing variations (errors), etc., are permitted. In addition, the opening area (cross-sectional area) of the foundation air intake vent 7 may change between the outdoor side 18 and the underfloor space 5 side.

[0024] [Ventilation System] The ventilation system 21 of this embodiment is used to ventilate the floor space 6 by supplying underfloor air Au, which includes outside air Ao, to the floor space 6. The ventilation system 21 of this embodiment includes a fan 22. Furthermore, the ventilation system 21 of this embodiment includes an air passage 23 and an exhaust fan 24, but is not particularly limited.

[0025] [fan] Fan 22 is used to supply underfloor air Au, which includes outside air Ao introduced from the foundation air intake 7, to the space above the floor 6. In this specification, "fan" is a machine for pressurizing and pumping air. Therefore, fan 22 and the exhaust fan 24 described later are not particularly limited as long as they are capable of pressurizing and pumping air.

[0026] In this embodiment, only one fan 22 is included, but the system is not limited to this configuration. For example, depending on the volume of the space above the floor 6, multiple fans (not shown) may be included. Also, in this embodiment, the fan 22 is capable of supplying underfloor air Au to the space above the floor 6 via the air passage 23, but the system is not limited to this configuration. For example, the fan 22 may be installed in a hole (not shown) formed in the floor 4 of the first floor, so that underfloor air Au can be supplied directly to the space above the floor 6 without going through the air passage 23.

[0027] The fan 22 in this embodiment is configured as a constant-airflow fan whose rotational speed is controlled to maintain a constant airflow. In this case, the rotational speed of the fan 22 is controlled by the control device 25, which allows the notch (airflow) to be switched. In this specification, "airflow" refers to the airflow per unit time (m³). 3 It is identified as / h).

[0028] [Airflow channel] The air passage 23 is composed of, for example, a duct placed in the piping space of the house H. Alternatively, the air passage 23 may be composed of, for example, a space enclosed by a partition wall (not shown). One end of the air passage 23 is located in the underfloor space 5. The other end of the air passage 23 is located in the above-floor space 6 (living room 15). This air passage 23 allows air to flow between the underfloor space 5 and the above-floor space 6.

[0029] In this embodiment, a fan 22 is installed in the air passage 23 so as to be able to supply underfloor air Au from the underfloor space 5 to the upper floor space 6. By driving this fan 22, the ventilation system 21 can supply (pressure-feed) underfloor air Au, including outside air Ao, to the upper floor space 6.

[0030] [Exhaust fan] The exhaust fan 24 is for exhausting the air Ai from the space above the floor (hereinafter sometimes referred to as "floor air") to the outdoors 18. In this embodiment, the exhaust fan 24 is installed in a ventilation opening 26 provided in the exterior wall 13, but it is not particularly limited. In addition, the exhaust fan 24 is designed to be operable based on a single airflow rate (single notch), but it may be designed to be operable based on multiple airflow rates. The operation of the exhaust fan 24 may be controlled by a control device 25.

[0031] [Control device] The control device 25 is used to control the operation of the fan 22. The control device 25 in this embodiment may also be used to control the operation of the exhaust fan 24 or the air conditioner 17. The control device 25 in this embodiment is composed of a computer and is installed, for example, in a partition wall.

[0032] Figure 3 is a conceptual diagram showing an example of the configuration of the control device 25. The control device 25 is composed of, for example, an arithmetic unit (CPU) 28, a storage device 29 for storing processing procedures, etc., and a working memory 30 for reading processing procedures, etc., from the storage device 29.

[0033] The control device 25 (arithmetic unit 28) is connected to an input device 31 and an output device 32. The input device 31 consists of operation buttons, a touch panel, etc. (not shown) provided on the housing of the control device 25 as shown in Figure 2. Through such an input device 31, data (information) entered by, for example, a user (resident) can be transmitted to the control device 25. On the other hand, the output device 32 is configured as a display (not shown) provided on the housing of the control device 25. When data from the control device 25 is received by such an output device 32, the operating status of, for example, the ventilation system 21 (fan 22 and exhaust fan 24) or the air conditioner 17 can be displayed.

[0034] [Arithmetic device] The arithmetic unit 28 in this embodiment is composed of, for example, a CPU (Central Processing Unit). The arithmetic unit 28 in this embodiment is communicatively connected to the fan 22, the exhaust fan 24, and the air conditioner 17. As a result, the operating status of the fan 22, the exhaust fan 24, and the air conditioner 17 can be grasped by the arithmetic unit 28. Furthermore, the operation of the fan 22, the exhaust fan 24, and the air conditioner 17 (including, for example, starting and stopping operation) can be controlled by the arithmetic unit 28.

[0035] In the ventilation system 21 of this embodiment, the operation of the fan 22 shown in Figure 2 is controlled by the control device 25 (calculation device 28). The operation (rotation) of this fan 22 supplies underfloor air Au, including outside air Ao introduced from the foundation air intake 7, to the above-floor space 6 via the air passage 23. As described above, the underfloor air Au (outside air Ao) exchanges heat with geothermal energy, which has little temperature change throughout the year, via the ground (concrete slab) 8. By supplying such underfloor air Au to the above-floor space 6, the comfort of the above-floor space 6 can be improved while reducing the air conditioning load of the air conditioner 17.

[0036] In the ventilation system 21 of this embodiment, the operation of the exhaust fan 24 is controlled by the control device 25 (calculation unit 28). The operation (rotation) of this exhaust fan 24 discharges the floor air Ai to the outdoors 18. If the exhaust fan 24 is not provided, the floor air Ai is discharged to the outdoors 18 through the ventilation opening 26 provided in the floor space 6. As a result, the ventilation system 21 ventilates the house H (floor space 6).

[0037] [How to design a residential ventilation system] Incidentally, in house H, although the airtightness of the first-floor floor 4 is enhanced, gaps (not shown in the diagram) inevitably exist in the first-floor floor 4 due to reasons such as the expansion and contraction of the wood. As a result, the air above the floor Ai (shown by the dashed line) can pass through the gaps in the first-floor floor 4 into the underfloor space 5. When the amount of air above the floor Ai entering this underfloor space 5 increases, the proportion of outside air Ao contained in the underfloor air Au, which serves as the ventilation air for the above-floor space 6, decreases. Therefore, there was room for further improvement in ensuring proper ventilation based on the required number of air changes per unit time.

[0038] In this embodiment, a ventilation system 21 for a house capable of proper ventilation is designed. The computer 1 shown in Figure 1 is used to design this ventilation system 21. Figure 4 is a flowchart showing an example of the processing procedure for the design method of the ventilation system for house H.

[0039] [Calculate the required ventilation rate for a house] In the design method of this embodiment, first, the required ventilation rate V per unit time for the house H shown in Figure 2 is determined (step S1). The required ventilation rate V in this embodiment is determined by the computer 1 shown in Figure 1, but is not particularly limited and may be calculated by, for example, a designer.

[0040] The required ventilation volume V can be appropriately determined as long as the air in the above-floor space 6 (above-floor air Ai) shown in FIG. 2 can be maintained in a hygienic state. In the present embodiment, the required ventilation volume V is obtained by multiplying the air volume of the house H by a predetermined required ventilation frequency per unit time.

[0041] The air volume of the house H is the volume of the above-floor space 6. Therefore, the floor area (m 2 ) of the above-floor space 6 is multiplied by the ceiling height (m), thereby obtaining the air volume (m 3 ) of the house H. Note that the calculated floor area and ceiling height used for calculating the air volume can be easily calculated based on CAD data of the house H, for example.

[0042] The required ventilation frequency is the number of ventilations required per unit time (e.g., 1 hour) in the house H. In the present embodiment, the required ventilation frequency is set to 0.5 times / h, but is not particularly limited.

[0043] In step S1, the air volume (m 3 ) of the house H is multiplied by the required ventilation frequency per unit time (0.5 times / h in this example). Thereby, the required ventilation volume V (m 3 / h) per unit time for the house H is obtained. The required ventilation volume V is stored in the computer 1 shown in FIG. 1.

[0044] [Obtaining effective ventilation volume rate] Next, in the design method of the present embodiment, the effective ventilation volume rate R is obtained (step S2). The effective ventilation volume rate R is the proportion of outdoor air Ao contained in the air supplied to the above-floor space 6 (i.e., under-floor air Au) by the operation of the ventilation system 21 (fan 22) shown in FIG. 2. The effective ventilation volume rate R of the present embodiment is obtained by the computer 1 shown in FIG. 1, but is not particularly limited thereto, and may be calculated by a designer, for example.

[0045] In step S2 of the present embodiment, the effective ventilation volume rate R defined by the following formula is obtained. R=A / (A+B) B=C×D Here, R: Effective ventilation rate A: Opening area of ​​the foundation air intake (cm²) 2 ) B: Equivalent gap area of ​​the first floor (cm²) 2 ) C: Amount of gaps per unit area of ​​the first floor (cm 2 / m 2 ) D: Total floor area of ​​the first floor (m²) 2 )

[0046] Opening area A (cm²) of the foundation air intake vent 7 2 ) can be determined as appropriate. As shown in Figure 2, the foundation air intake 7 of this embodiment penetrates from the outdoor 18 side to the underfloor space 5 side with the same opening area (cross-sectional area), so the opening area A can be uniquely identified. If the opening area (cross-sectional area) of the foundation air intake 7 changes between the outdoor 18 side and the underfloor space 5 side, the smallest opening area (cross-sectional area) is identified as the opening area A.

[0047] As in this embodiment, if the foundation air intake 7 consists of only one unit, the opening area A can be determined from that unit. On the other hand, if multiple foundation air intake 7 units are provided, the sum of their opening areas can be used to determine the opening area A.

[0048] The opening area A can be easily calculated based on the CAD data of house H. The opening area A is stored in computer 1 shown in Figure 1.

[0049] Equivalent gap area B (cm²) of floor 4 on the 1st floor 2 ) is the amount of air leakage C (cm²) per unit area of ​​the floor 4 on the first floor. 2 / m 2 ) and the total area D(m²) of the 1st floor 4. 2 It can be found by multiplying by ).

[0050] The amount of air gap per unit area of ​​the first floor 4 (cm) 2 / m 2) can be determined as appropriate. In this embodiment, the gap amount C is determined in accordance with JIS-A2201 "Test method for airtightness performance of houses, etc. using a blower". First, in an experimental building that reproduces the space above the floor 6 and the space below the floor 5, with the building materials other than the floor 4 of the first floor (ceiling 12, exterior walls 13, etc.) airtight, the gap area is determined by considering the space below the floor 5 as the interior and the space above the floor 6 as the exterior. Then, by dividing this gap area by the total floor area, the gap amount C per unit area is determined. Such a gap amount C varies depending on the material and structure of the floor 4 of the first floor. Therefore, it is preferable that the floor 4 installed in the experimental building for obtaining the gap amount C be the same specifications as the floor 4 of the first floor of the house H in which the ventilation system 21 is designed.

[0051] Total floor area D(m²) 2 The total area D is determined at the floor 4 on the first floor of house H where the ventilation system 21 is installed. Therefore, the total area D varies depending on the plan (floor layout) of house H. Such a total area D can be easily calculated based on the CAD data of house H.

[0052] And the amount of gap C (cm) per unit area of ​​the floor 4 on the first floor 2 / m 2 ) and the total area D(m²) of the 1st floor 4. 2 When multiplied by ), the equivalent gap area B (cm²) of the floor 4 on the first floor is calculated. 2 ) is required.

[0053] The equivalent gap area B correlates with the amount of floor air Ai (shown by the dashed line) entering the underfloor space 5. On the other hand, the opening area A (cm²) of the foundation air intake 7 is correlated with the amount of floor air Ai (shown by the dashed line). 2 This correlates with the amount of outside air Ao supplied to the underfloor space 5. By dividing the opening area A by the sum of these opening areas A and equivalent gap area B, the proportion of outside air Ao contained in the underfloor air Au used as ventilation air for the above-floor space 6 can be determined. This proportion of outside air Ao is determined as the effective ventilation rate R. The effective ventilation rate R is stored in the computer 1 shown in Figure 1.

[0054] [Determine the standard airflow for the fan] Next, in the design method of this embodiment, the standard airflow rate of the fan 22 shown in Figure 2 is determined (step S3). The standard airflow rate is the airflow rate per unit time required of the fan 22 to perform proper ventilation based on the required number of ventilations (0.5 times / h in this example).

[0055] In step S3 of this embodiment, the required ventilation rate V(m³) for the house H shown in Figure 2 is calculated. 3 The amount of underfloor air Au supplied (m³ / h) is divided by the effective ventilation rate R. This allows the ventilation system 21 that supplies underfloor air Au (including outside air Ao and above-floor air Ai (shown by the dashed line) that enters the underfloor space 5) to secure the required ventilation rate V (required air changes per hour) to determine the amount of underfloor air Au supplied (m³ / h). 3 The amount of underfloor air Au supplied ( / h) is determined. This determined amount of underfloor air Au is determined as the reference airflow rate for fan 22. The reference airflow rate is stored in computer 1 shown in Figure 1.

[0056] [Select fans] Next, in the design method of this embodiment, the fan 22 shown in Figure 2 is selected (step S4). In step S4 of this embodiment, an airflow of (m³) or more than the standard airflow is selected. 3 A fan 22 with power capable of supplying underfloor air Au is selected at / h). In this embodiment, the selection of the fan 22 is performed by the computer 1 shown in Figure 1, but is not particularly limited and may be performed by, for example, the designer of the ventilation system 21.

[0057] In step S4, a fan 22 with power capable of operating at an airflow rate equal to or greater than the standard airflow rate is selected from among several fans 22 with different specifications such as power. By installing such a fan 22 in the ventilation system 21 of the house H, it becomes possible to perform proper ventilation based on the required ventilation rate (0.5 times / hour in this example). Furthermore, it prevents the selection of a fan 22 with unnecessarily high power. This suppresses the ventilation rate from becoming unnecessarily high and can prevent an increase in the initial cost of the ventilation system 21. In addition, a fan 22 with a maximum airflow rate greater than the standard airflow rate may be selected in order to adjust the airflow rate according to changes in the environment of the house H. The selected fan 22 is stored in the computer 1 shown in Figure 1.

[0058] In step S4, the exhaust fan 24 shown in Figure 2 may be selected. In this embodiment, the exhaust fan 24 may be selected that has power capable of exhausting the floor air Ai with an airflow rate equal to or greater than the standard airflow rate. This can prevent the floor space 6 from becoming excessively positive pressure.

[0059] [Installation of a ventilation system including fans] Next, in the design method of this embodiment, the ventilation system 21 including the selected fan 22 is installed in the house H (step S5). In step S5, the selected fan 22 is installed in the house H. Furthermore, in step S5, the air passage 23 is installed.

[0060] In step S5 of this embodiment, one end of the air passage 23 is positioned in the underfloor space 5. Furthermore, a fan 22 is connected to one end of the air passage 23. The other end of the air passage 23 is positioned in the above-floor space 6. This allows a ventilation system 21 capable of proper ventilation to be installed in the house H. In addition, in step S5 of this embodiment, a selected exhaust fan 24 may be installed in the above-floor space 6.

[0061] In the design method of this embodiment, a fan 22 with power capable of operating at an airflow rate equal to or greater than the standard airflow rate is installed, making it possible to perform appropriate ventilation based on the required number of air changes. Furthermore, it prevents the installation of a fan 22 with unnecessarily large power. For this reason, in the design method of this embodiment, an unnecessarily large number of air changes is suppressed, and an increase in the initial cost and running cost of the ventilation system 21 can be prevented.

[0062] In the design method of this embodiment, the opening area A of the foundation air intake 7 is set to 500 cm². 2 The above may include adjustment steps (not shown). This suppresses a decrease in the effective ventilation rate R, thus potentially discouraging the selection of a fan 22 with high power. On the other hand, if the opening area A becomes unnecessarily large, the amount of outside air Ao introduced into the underfloor space 5 becomes unnecessarily large, reducing the heat exchange efficiency with geothermal energy. From this perspective, the opening area A should be 800 cm². 2 The following adjustments may be made. Note that the opening area A can be easily adjusted, for example, by opening and closing the foundation air intake 7 with a cover (not shown).

[0063] The design method of this embodiment may include a step (not shown) of adjusting the opening area of ​​the access opening 10 so that the pressure difference between the multiple spaces 5a and 5b is 0.12 Pa or less when the fan 22 is in operation. By keeping the pressure difference at 0.12 Pa or less when the fan 22 is in operation, the space 5a where the fan 22 is located becomes locally negative pressure, which suppresses an increase in the amount of above-floor air Ai (shown by the dashed line) entering the underfloor space 5. This prevents the proportion of outside air Ao contained in the underfloor air Au from decreasing, making it possible to perform proper ventilation based on the required number of air changes. The opening area can be easily adjusted, for example, by opening and closing the access opening 10 with a cover or the like (not shown).

[0064] [Ventilation method for houses (first embodiment)] Next, the ventilation method for the house according to this embodiment (hereinafter sometimes referred to as the "ventilation method") will be described. In the ventilation method of this embodiment, the house H is ventilated using the ventilation system 21 shown in Figure 2.

[0065] The ventilation method of this embodiment is carried out by the control device 25 shown in Figure 3. Figure 5 is a flowchart showing an example of the processing procedure for the ventilation method of house H.

[0066] [Calculate the required ventilation rate for a house] In the ventilation method of this embodiment, first, the required ventilation rate V per unit time of the house H is determined (step S11). In step S11, based on the same procedure as step S1 shown in Figure 4, the control device 25 shown in Figure 3 calculates the required ventilation rate V by multiplying the volume of the house H shown in Figure 2 by a predetermined required number of ventilations per unit time.

[0067] The required ventilation volume V is stored in the memory device 29 shown in Figure 3. If the required ventilation volume V determined during step S1 shown in Figure 4 is already stored in the memory device 29 prior to the implementation of the ventilation method, that required ventilation volume V may be used.

[0068] [Calculate the effective ventilation rate] Next, in the ventilation method of this embodiment, the effective ventilation rate R is determined (step S12). The control device 25 shown in Figure 3 determines the effective ventilation rate R, which is defined by the following formula, based on the same procedure as in step S2 shown in Figure 4. R = A / (A + B) B = C × D Here, R: Effective ventilation rate A: Opening area of ​​the foundation air intake (cm²) 2 ) B: Equivalent gap area of ​​the first floor (cm²) 2 ) C: Amount of gaps per unit area of ​​the first floor (cm 2 / m 2 ) D: Total floor area of ​​the first floor (m²) 2)

[0069] The effective ventilation rate R obtained in step S12 is stored in the memory device 29 shown in Figure 3. If the effective ventilation rate R obtained during step S2, shown in Figure 4, is already stored in the memory device 29 prior to the implementation of the ventilation method, that effective ventilation rate R may be used.

[0070] [Determine the standard airflow for the fan] Next, in the ventilation method of this embodiment, the standard airflow rate of the fan 22 is determined (step S13). As described above, the standard airflow rate is the airflow rate per unit time required of the fan 22 in order to perform proper ventilation based on the required number of air changes. This standard airflow rate is determined by the control device 25 shown in Figure 3, which divides the required ventilation rate V by the effective ventilation rate R, based on the same procedure as in step S3 shown in Figure 4.

[0071] The standard airflow rate determined in step S13 is stored in the memory device 29 shown in Figure 3. If the standard airflow rate determined during the design of the ventilation system 21 is already stored in the memory device 29 prior to the implementation of the ventilation method, that standard airflow rate may be used.

[0072] [Operate the fan (operation step)] Next, in the ventilation method of this embodiment, the fan 22 is operated at an airflow rate equal to or greater than the standard airflow rate (operation step S14). In operation step S14, the control device 25 shown in Figure 3 operates the fan 22 based on a notch (airflow rate) equal to or greater than the standard airflow rate among the notches (airflow rates) that the fan 22 can control.

[0073] In the ventilation method of this embodiment, the fan 22 is operated at an airflow rate equal to or greater than the standard airflow rate required for proper ventilation based on the required number of air changes, thereby enabling proper ventilation based on the required number of air changes. Furthermore, by controlling the operation of the fan 22 based on the standard airflow rate, the power consumption of the fan 22 is prevented from becoming unnecessarily high, thus preventing an increase in running costs.

[0074] In operation step S14, the air conditioner 17 may be operated. For example, in summer, the room temperature in the floor space 6 may be lowered by operating the air conditioner 17 for cooling. On the other hand, in winter, the room temperature in the floor space 6 may be raised by operating the air conditioner 17 for heating. As a result, in operation step S14, the comfort level of the floor space 6 is improved while performing appropriate ventilation based on the required ventilation rate.

[0075] [Determine whether or not to issue an order to shut down the ventilation system] Next, in the ventilation method of this embodiment, it is determined whether or not there is an instruction to stop the operation of the ventilation system 21 (step S15). The determination of whether or not there is an instruction to stop operation is performed by the control device 25 shown in Figure 3, based on, for example, instruction information entered by a user (resident) or the like into the input device 31 (shown in Figure 3), or the occurrence of an abnormal termination such as an interrupt process.

[0076] If it is determined that there is an instruction to stop operation ("Yes" in step S15), step S16 is performed to stop the operation of the ventilation system 21.

[0077] On the other hand, if it is determined that there is no instruction to stop operation (No in step S15), the operation steps S14 and S15 are performed again. As a result, in the ventilation method of this embodiment, the fan 22 continues to operate at an airflow rate equal to or greater than the standard airflow rate until an instruction to stop operation is given, so that proper ventilation based on the required number of ventilations can be maintained.

[0078] [Stop the ventilation system] Next, in the ventilation method of this embodiment, the operation of the ventilation system 21 shown in Figure 2 is stopped (step S16). In step S16 of this embodiment, the control device 25 shown in Figure 3 stops the operation of the fan 22 and the exhaust fan 24. If the fan 22 and the exhaust fan 24 have already been stopped, their operation may be continued to be stopped.

[0079] [Ventilation method for houses (Second embodiment)] In the ventilation method of the previous embodiment, the fan 22 was operated based on the standard airflow rate regardless of whether the air conditioner 17 was in cooling operation or not, but the invention is not limited to this embodiment. Figure 6 shows an example of a house H in cooling operation.

[0080] When the air conditioner 17 is in cooling mode, cool conditioned air Ac is supplied to the space above the floor 6 (living room 15). As the temperature of the space above the floor 6 decreases due to this conditioned air Ac, the amount of air above the floor Ai (shown by the dashed line) supplied to the space below the floor 5 becomes relatively larger. On the other hand, the effective ventilation rate R calculated in step S12 does not take into account the increase in the amount of air above the floor Ai supplied during cooling operation. Therefore, the actual effective ventilation rate during cooling operation is smaller than the effective ventilation rate R calculated in step S12. Consequently, when the fan 22 is operated during cooling operation based on the standard airflow rate calculated from the effective ventilation rate R, it may become difficult to perform proper ventilation based on the required number of air changes.

[0081] In this embodiment of the ventilation method, when the air conditioner 17 is in cooling operation, the fan 22 is operated at a second airflow that is greater than the first airflow, which is greater than or equal to the standard airflow. Figure 7 is a flowchart illustrating the processing procedure of the ventilation method for a house H according to another embodiment of the present invention. Figure 8 is a flowchart showing an example of the processing procedure of operation step S14 in another embodiment of the present invention.

[0082] [Determine whether or not the air conditioner is running] In the operation step S14 of this embodiment, it is first determined whether or not the air conditioner 17 shown in Figure 6 is in cooling operation (step S21). The determination of whether or not it is in cooling operation is performed by a control device 25 (shown in Figure 3) which is communicatively connected to the air conditioner 17.

[0083] If it is determined that the air conditioning is not in operation (No in step S21), the first operation step S22 is performed. On the other hand, if it is determined that the air conditioning is in operation (Yes in step S21), the second operation step S23 is performed.

[0084] [Operate the fan at the first airflow level (first operation step)] Next, in the operation step S14 of this embodiment, the fan 22 is operated at a first airflow rate which is equal to or greater than the standard airflow rate (first operation step S22). In the first operation step S22 of this embodiment, similar to the operation step S14 of previous embodiments, the control device 25 shown in Figure 3 operates the fan 22 based on a first airflow rate (notch) which is equal to or greater than the standard airflow rate among the notches (airflow rates) that the fan 22 can control.

[0085] The first operating step S22 is performed when the air conditioner 17 is not in cooling operation (No in step S21), as shown in Figure 2. In this case, the amount of floor air Ai supplied does not increase as it does during cooling operation as shown in Figure 6. Therefore, the effective ventilation rate in the first operating step S22 can be treated as the effective ventilation rate R obtained in step S12 as shown in Figure 7. Thus, in the first operating step S22, by operating the fan 22 based on the first airflow rate (airflow rate equal to or greater than the standard airflow rate), it becomes possible to perform appropriate ventilation based on the required number of air changes. Furthermore, by controlling the operation of the fan 22 based on the first airflow rate, the power consumption of the fan 22 is prevented from becoming unnecessarily large, thus preventing an increase in running costs.

[0086] [Operate the fan at the second airflow setting (second operating step)] Next, in the operation step S14 of this embodiment, the fan 22 is operated at a second airflow rate that is greater than the first airflow rate (second operation step S23). In the first operation step S22 of this embodiment, the control device 25 shown in Figure 3 operates the fan 22 based on a second airflow rate (notch) that is greater than the first airflow rate among the notches (airflow rates) that can be controlled by the fan 22.

[0087] In the first operating step S22, as shown in Figure 6, the air conditioner 17 is in cooling operation ("Yes" in step S21). In this case, the amount of floor air Ai (shown by the dashed line) supplied to the underfloor space 5 becomes relatively large, so the actual effective ventilation rate becomes smaller than the effective ventilation rate R obtained in step S12 shown in Figure 7. Therefore, in the second operating step S23, the fan 22 is operated at a second airflow rate that is larger than the first airflow rate, making it possible to perform proper ventilation based on the required number of air changes. To effectively exert this effect, it is preferable that the second airflow rate be set to 1.1 to 1.5 times the first airflow rate.

[0088] Furthermore, the amount of floor air Ai (shown by the dashed line) supplied to the underfloor space 5 tends to increase in proportion to the temperature difference between the floor space 6 and the outside air Ao when the temperature of the floor space 6 is lower than the temperature of the outside air Ao (for example, in summer). For this reason, the value multiplied by the first airflow rate when determining the second airflow rate may be increased in proportion to the temperature difference. As a result, the second airflow rate is adjusted appropriately according to the constantly changing temperature difference (i.e., the amount of floor air Ai supplied), which can suppress increases in running costs while ensuring proper ventilation based on the required number of air changes.

[0089] Although particularly preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the illustrated embodiments and can be implemented in various modified forms. [Examples]

[0090] Based on the processing procedure shown in Figure 4, the ventilation system for the house was designed (Example). This house has an inner garage and a large earthen floor on the first floor, with a total floor area of ​​120.08 m². 2 ) For the total floor area D of the first floor is 30m 2 It is made smaller. In the example, for such a house, the steps of determining the required ventilation rate V per unit time of the house and determining the effective ventilation rate R defined by the above formula were carried out. The effective ventilation rate R in the example was 0.97.

[0091] In the embodiment, the required ventilation volume V was divided by the effective ventilation rate R (i.e., 0.97) to determine the standard airflow rate, which is the airflow rate per unit time required for the fan. Then, in the embodiment, the step of selecting a fan with power capable of supplying air to the underfloor space at an airflow rate equal to or greater than the standard airflow rate was performed.

[0092] For comparison, in the above-mentioned house in which the total floor area D of the first floor is smaller than the total floor area, the effective ventilation rate was uniformly determined without considering the above formula (i.e., the opening area A of the foundation air supply, the amount of gaps per unit area of ​​the first floor C, and the total area D (house plan)) (comparative example). In the comparative example, the required number of air changes is ensured by overestimating the proportion of air supplied from above the floor to the underfloor space (i.e., underestimating the proportion of outside air contained in the underfloor air supplied to the underfloor space). The effective ventilation rate for this comparative example was determined to be 0.91, which is smaller than the effective ventilation rate in the example.

[0093] In the comparative example, the required ventilation volume V was divided by the effective ventilation rate (i.e., 0.91) to determine the airflow rate per unit time required from the fan. In the comparative example, a fan with power capable of supplying air to the underfloor space at an airflow rate equal to or greater than the determined rate was selected. The common specifications are as follows: Total floor area: 120.08 m² 2 Ventilation rate: 0.5 times / hour Foundation air intake opening area A: 500 cm² 2 Equivalent gap area B on the first floor: 15cm 2 Air gap per unit area of ​​the first floor: C: 0.5cm 2 / m 2 Total floor area of ​​the first floor: D: 30m 2

[0094] The test results showed that, in the example, the effective ventilation rate R, which indicates the proportion of outside air in the air supplied to the floor space, was accurately determined based on the opening area A of the foundation air intake and the equivalent gap area B of the first-floor floor. By dividing the required ventilation rate V by this effective ventilation rate R, a standard airflow rate was obtained, and a fan was selected based on this, thereby designing a ventilation system capable of performing appropriate ventilation based on the required number of air changes. Furthermore, by ventilating the house using the designed ventilation system based on the processing procedure shown in Figure 5, appropriate ventilation was achieved.

[0095] On the other hand, in the comparative example, the fan was selected based on the airflow obtained by dividing the required ventilation rate V by an effective ventilation rate that underestimated the proportion of outside air. As a result, a fan with unnecessarily large power was selected, and a ventilation system was designed with an unnecessarily large number of ventilation cycles. In this comparative example, the selection of a fan with unnecessarily large power increased the initial cost of the ventilation system. Furthermore, in the comparative example, when the house was ventilated using the designed ventilation system, the primary energy consumption for ventilation (MJ / year) was 5% higher than in the example, resulting in increased running costs.

[0096] Therefore, the example demonstrated that, while providing appropriate ventilation based on the required ventilation rate, it reduced initial and running costs compared to the comparative example.

[0097] [Note] The present invention includes the following embodiments.

[0098] [Invention 1] A method for designing a ventilation system for a house, The house includes an insulated foundation, a first-floor floor, an underfloor space partitioned by the foundation and the first-floor floor, an upper floor space provided above the underfloor space via the first-floor floor, and a foundation air intake provided in the foundation for introducing outside air into the underfloor space. The ventilation system includes a fan for supplying air from the underfloor space, including the outside air introduced from the foundation air intake, to the above-floor space. The aforementioned design method is The steps include determining the required ventilation rate V per unit time for the aforementioned house, The steps include: determining the effective ventilation rate R defined by the following formula, The steps include: dividing the required ventilation volume V by the effective ventilation rate R to determine the standard airflow, which is the airflow per unit time required for the fan; The step of selecting a fan having power capable of supplying air to the underfloor space at an airflow rate equal to or greater than the standard airflow rate, How to design a ventilation system for a house. R = A / (A + B) B = C × D Here, R: Effective ventilation rate A: Opening area of ​​the foundation air intake (cm²) 2 ) B: Equivalent gap area of ​​the first floor (cm²) 2 ) C: Amount of gaps per unit area of ​​the first floor (cm 2 / m 2 ) D: Total floor area of ​​the first floor (m²) 2 ) [Invention 2] The method for designing a ventilation system for a house according to Invention 1, wherein the required ventilation rate V is determined by multiplying the volume of the house by a predetermined required number of ventilations per unit time. [Invention 3] A method of ventilating a house, The house includes an insulated foundation, a first-floor floor, an underfloor space partitioned by the foundation and the first-floor floor, an upper floor space provided above the underfloor space via the first-floor floor, a foundation air intake provided in the foundation for introducing outside air into the underfloor space, and a fan for supplying the air from the underfloor space, including the outside air introduced from the foundation air intake, to the upper floor space. The aforementioned ventilation method is The steps include determining the required ventilation rate V per unit time for the aforementioned house, The steps include: determining the effective ventilation rate R defined by the following formula, The steps include: dividing the required ventilation volume V by the effective ventilation rate R to determine the standard airflow, which is the airflow per unit time required for the fan; The operation step includes operating the fan at an airflow rate equal to or greater than the aforementioned standard airflow rate, Ventilation methods for houses. R = A / (A + B) B = C × D Here, R: Effective ventilation rate A: Opening area of ​​the foundation air intake (cm²) 2 ) B: Equivalent gap area of ​​the first floor (cm²) 2 ) C: Amount of gaps per unit area of ​​the first floor (cm 2 / m 2 ) D: Total floor area of ​​the first floor (m²) 2 ) [4th Invention] The method for ventilating a house according to the present invention, wherein the required ventilation rate V is determined by multiplying the volume of the house by a predetermined required number of ventilations per unit time. [5th ​​Invention] The aforementioned residence includes an air conditioner capable of cooling operation, The aforementioned driving step is, When the air conditioner is not in cooling operation, the first operating step involves operating the fan at a first airflow rate which is equal to or greater than the standard airflow rate, A method for ventilating a house according to the present invention 3 or 4, comprising a second operating step of operating the fan at a second airflow rate greater than the first airflow rate when the air conditioner is in cooling operation. [Explanation of Symbols]

[0099] H Housing 5 Underfloor space 21 Ventilation System 22 Fans

Claims

1. A method for designing a ventilation system for a house, The house includes an insulated foundation, a first-floor floor, an underfloor space partitioned by the foundation and the first-floor floor, an upper floor space provided above the underfloor space via the first-floor floor, and a foundation air intake provided in the foundation for introducing outside air into the underfloor space. The ventilation system includes a fan for supplying air from the underfloor space, including the outside air introduced from the foundation air intake, to the above-floor space. The aforementioned design method is The steps include determining the required ventilation rate V per unit time for the aforementioned house, The steps include: determining the effective ventilation rate R defined by the following formula, The steps include: dividing the required ventilation volume V by the effective ventilation rate R to determine the standard airflow, which is the airflow per unit time required for the fan; The step of selecting a fan having power capable of supplying air to the underfloor space at an airflow rate equal to or greater than the standard airflow rate, How to design a ventilation system for a house. R = A / (A + B) B = C × D Here, R: Effective ventilation rate A: Opening area of ​​the foundation air intake (cm²) 2 ) B: Equivalent gap area of ​​the first floor (cm²) 2 ) C: Amount of gaps per unit area of ​​the first floor (cm 2 / m 2 ) D: Total floor area of ​​the first floor (m²) 2 )

2. The method for designing a ventilation system for a house according to claim 1, wherein the required ventilation rate V is determined by multiplying the volume of the house by a predetermined required number of ventilations per unit time.

3. A method of ventilating a house, The house includes an insulated foundation, a first-floor floor, an underfloor space partitioned by the foundation and the first-floor floor, an upper floor space provided above the underfloor space via the first-floor floor, a foundation air intake provided in the foundation for introducing outside air into the underfloor space, and a fan for supplying the air from the underfloor space, including the outside air introduced from the foundation air intake, to the upper floor space. The aforementioned ventilation method is The steps include determining the required ventilation rate V per unit time for the aforementioned house, The steps include: determining the effective ventilation rate R defined by the following formula, The steps include: dividing the required ventilation volume V by the effective ventilation rate R to determine the standard airflow, which is the airflow per unit time required for the fan; The operation step includes operating the fan at an airflow rate equal to or greater than the aforementioned standard airflow rate, Ventilation methods for houses. R = A / (A + B) B = C × D Here, R: Effective ventilation rate A: Opening area of ​​the foundation air intake (cm²) 2 ) B: Equivalent gap area of ​​the first floor (cm²) 2 ) C: Gap volume per unit area of the first-floor floor (cm 2 / m 2 ) D: Total floor area of ​​the first floor (m²) 2 )

4. The method for ventilating a house according to claim 3, wherein the required ventilation rate V is determined by multiplying the volume of the house by a predetermined required number of ventilations per unit time.

5. The aforementioned residence includes an air conditioner capable of cooling operation, The aforementioned driving step is, When the air conditioner is not in cooling operation, the first operating step involves operating the fan at a first airflow rate which is equal to or greater than the standard airflow rate, A method for ventilating a house according to claim 3 or 4, comprising a second operating step of operating the fan at a second airflow rate greater than the first airflow rate when the air conditioner is in cooling operation.

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