Heat loss amount calculation system

Abstract

To provide a heat loss amount calculation system capable of easily calculating a heat loss amount in an outer skin part of a unit type building.SOLUTION: In a heat loss amount calculation apparatus, a roof area calculation unit 42 calculates an area of a roof part based on design data of a building, a girder total length calculation unit 44 calculates the total length of all ceiling girders constituting thermal bridge parts in the roof part based on the design data of the building, a thermal bridge pitch calculation unit 45 calculates a thermal bridge pitch indicating a ratio of the area occupied by the ceiling girders in the roof part based on the calculated area of the roof part and the total length of the ceiling girders, a heat transmission coefficient calculation unit 47 calculates a heat transmission coefficient of the roof part based on the thermal bridge pitch calculated by the thermal bridge pitch calculation unit 45 and a correspondence relationship between the thermal bridge pitch and the heat transmission coefficient stored in a heat transmission coefficient database 46, and a heat loss amount calculation unit 48 calculates a heat loss amount in the roof part based on the calculated heat transmission coefficient and the area of the roof part.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a heat loss amount calculation system for calculating the heat loss amount in the outer skin portion of a unit building.

Background Art

[0002] In recent years, from the perspective of energy conservation and the like, buildings with excellent heat insulation performance have been demanded, and some heat insulation performance calculation systems for calculating the heat insulation performance of buildings have been proposed. For example, Patent Document 1 discloses a system for calculating the heat loss amount in the outer skin portion of a building, such as the roof portion, the floor portion (first floor portion), and the outer wall portion, as the heat insulation performance of a unit building.

[0003] Here, as is well known, a unit building is constructed by combining a plurality of building units with each other. A building unit has a frame formed by connecting columns, ceiling girders, and floor girders in a rectangular parallelepiped shape. In a unit building, the girders and columns of the building units arranged in the outer skin portion become heat bridge portions. For example, in the roof portion, the ceiling girder becomes a heat bridge portion, and specifically, the ceiling girders facing each other in adjacent building units become heat bridge portions. Therefore, in a unit building, when calculating the heat loss amount of the roof portion, a heat bridge model including the two opposing ceiling girders is assumed, and a method of calculating it as if the heat bridge model is arranged at a plurality of locations in the roof portion can be considered.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in unit-type buildings, adjacent building units may be installed at a distance from each other. In such buildings, the space between adjacent building units is used as a staircase installation space or a storage space for items. And in such buildings, there will be a part where the distance between adjacent building units (and thus the distance between two opposing ceiling girders) is small and a part where the distance between adjacent building units is large. In recent years, with the diversification of needs for unit-type buildings, etc., the distances between building units vary, and the variations of buildings tend to increase.

[0006] Here, in the above-described method for calculating the heat loss amount using a heat bridge model including two opposing ceiling girders, the heat transfer coefficient of the heat bridge model will change depending on the distance between the two ceiling girders. Therefore, when applying the above calculation method to a unit-type building in which there are parts where the distance between adjacent building units (and thus the distance between two opposing ceiling girders) is small and large, it is necessary to prepare a plurality of heat bridge models for each distance between the two opposing ceiling girders.

[0007] However, preparing heat bridge models for each distance between two opposing ceiling girders is troublesome, and when calculating the heat loss amount, if the heat loss amount is calculated based on a plurality of types of heat bridge models, the calculation process will become complicated.

[0008] Note that such a problem is not limited to the case of calculating the heat loss amount of the roof part, but also occurs in the same way when calculating the heat loss amount of the outer skin part other than the roof part, such as the floor part (first floor part) and the outer wall part.

[0009] The present invention has been made in view of the above circumstances, and the main object is to provide a heat loss amount calculation system capable of easily calculating the heat loss amount in the outer skin part of a unit-type building.

Means for Solving the Problem

[0010] To solve the above problems, a heat loss amount calculation system according to a first invention is a heat loss amount calculation system that targets an outer skin portion, which is any one of a roof portion, a floor portion, and an outer wall portion of a building, and calculates a heat loss amount in the outer skin portion in a unit-type building constructed by combining a plurality of building units in which columns and beams as structural members are connected in a rectangular parallelepiped shape. The heat loss amount calculation system includes: an outer skin area calculation means for calculating the area of the outer skin portion based on the design data of the building; a total length calculation means for calculating a total length obtained by summing the lengths of all the heat bridge structural members in the outer skin portion, where the opposing structural members of adjacent building units among the structural members included in the outer skin portion are heat bridge structural members constituting a heat bridge portion, based on the design data of the building; a heat bridge ratio calculation means for calculating a heat bridge ratio indicating a ratio of an area occupied by the heat bridge structural members in the outer skin portion based on the area of the outer skin portion calculated by the outer skin area calculation means and the total length of the heat bridge structural members calculated by the total length calculation means; a storage means in which a correspondence relationship between the heat bridge ratio and the heat transfer coefficient in the outer skin portion is stored in advance; a heat transfer coefficient calculation means for calculating the heat transfer coefficient of the outer skin portion based on the heat bridge ratio calculated by the heat bridge ratio calculation means and the correspondence relationship stored in the storage means; and a heat loss amount calculation means for calculating the heat loss amount in the outer skin portion based on the heat transfer coefficient of the outer skin portion calculated by the heat transfer coefficient calculation means and the area of the outer skin portion calculated by the outer skin area calculation means.

[0011] According to the first invention, based on the design data of the unit-type building, the area of the outer skin portion (roof portion, floor portion, or outer wall portion) of the building is calculated, and the total length obtained by summing the lengths of all the heat bridge structural members in the outer skin portion is calculated. Then, based on the calculated area of the outer skin portion and the total length of the heat bridge structural members, a heat bridge ratio indicating the ratio of the area occupied by the heat bridge structural members in the outer skin portion is calculated. In the storage means, the correspondence relationship between the heat bridge ratio and the heat transfer coefficient in the outer skin portion is stored in advance. Then, based on the calculated heat bridge ratio and the above-mentioned correspondence relationship stored in the storage means, the heat transfer coefficient of the outer skin portion is calculated, and based on the calculated heat transfer coefficient and the calculated area of the outer skin portion, the heat loss amount in the outer skin portion is calculated.

[0012] In the flow of calculating the heat loss amount like this, the heat loss amount of the outer skin part is calculated by regarding each structural material (each heat bridge structural material) facing each other of adjacent building units as one heat bridge part. Therefore, unlike the case of calculating the heat loss amount using a heat bridge model including two opposing structural materials, it is not necessary to deliberately prepare a heat bridge model for each interval between the opposing structural materials. Further, since there is only one pattern as the heat bridge model (that is, only the pattern of one heat bridge structural material), the process of calculating the heat loss amount does not become so complicated, and as a result, it becomes possible to easily calculate the heat loss amount.

[0013] The heat loss amount calculation system of the second invention is, in the first invention, the building includes a small interval part where the interval between adjacent building units is small and a large interval part where the interval between adjacent building units is large.

[0014] According to the second invention, in a unit-type building, there are a part where the interval between adjacent building units is small and a part where the interval is large. That is, there are a part where the interval between the opposing heat bridge structural materials of adjacent building units is small and a part where the interval is large. Even in such a building, as described above, since the heat loss amount can be calculated with only one pattern as the heat bridge model, the heat loss amount can be easily calculated.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0016] An embodiment embodying the present invention will be described below with reference to the drawings. In this embodiment, a heat loss amount calculation device for calculating the heat loss amount at the roof of a pre-designed unit building is embodied. First, before explaining the heat loss amount calculation device, the configuration of the unit building will be described based on FIGS. 1 and 2. Note that FIG. 1 is a plan view showing the unit building, and FIG. 2 is a perspective view showing the building unit.

[0017] The unit building 10 (hereinafter simply referred to as the building 10) is constructed by combining a plurality of building units 20 having a rectangular parallelepiped shape. As shown in FIG. 2, the building unit 20 includes four columns 21 arranged at its four corners, and four ceiling girders 22 and four floor girders 23 that connect the upper and lower ends of each column 21, respectively. A rectangular parallelepiped frame 24 is formed by the columns 21, the ceiling girders 22, and the floor girders 23. The column 21 is made of square tubular steel. The ceiling girder 22 and the floor girder 23 are made of channel steel with a U-shaped cross-section, and their openings are arranged facing the inside in the horizontal direction. Note that the column 21, the ceiling girder 22, and the floor girder 23 respectively correspond to structural materials.

[0018] A plurality of ceiling joists 25 are spanned between the opposing ceiling girders 22 at a predetermined interval at the long side portion of the building unit 20. Also, a plurality of floor joists 26 are spanned between the opposing floor girders 23 at a predetermined interval at the long side portion of the building unit 20. For example, the ceiling joist 25 is made of lip channel steel, and the floor joist 26 is made of square steel. The ceiling surface material 27 is supported by the ceiling joist 25, and the floor surface material 28 is supported by the floor joist 26.

[0019] As shown in FIG. 1, the building 10 is a two-story building and includes a plurality of building units 20 arranged side by side in the first-floor part and the second-floor part, respectively. Above the second-floor part (in other words, the top-floor part), a roof part 13 as an outer skin part is provided. The roof part 13 is configured as a gable roof. The roof part 13 includes a ceiling girder 22 of each building unit 20 in the second-floor part, a roof material (not shown) supported from below by these ceiling girders 22, and a heat insulating material disposed in an inner region surrounded by four ceiling girders 22 of the building unit 20.

[0020] The ceiling girders 22 of each building unit 20 in the second-floor part of the building 10 include ceiling girders 22A facing each other of adjacent building units 20. In the roof part 13, these ceiling girders 22A constitute a thermal bridge part. Therefore, the ceiling girders 22A correspond to thermal bridge structural materials. In FIG. 1, each ceiling girder 22A is shown with dot hatching.

[0021] In the second-floor part of the building 10, there are a narrow interval part 14 where the intervals between adjacent side-by-side building units 20 are made small, and a wide interval part 15 where the above intervals are made large. In this case, the interval L1 between the opposing ceiling girders 22A of adjacent building units 20 via the wide interval part 15 is larger than the interval L2 between the opposing ceiling girders 22A of adjacent building units 20 via the narrow interval part 14.

[0022] Next, a heat loss amount calculation device 30 for calculating the heat loss amount in the roof part 13 will be described with reference to FIG. 3. FIG. 3 is a diagram showing a schematic configuration of the heat loss amount calculation device 30.

[0023] As shown in FIG. 3, the heat loss amount calculation device 30 is configured by a personal computer and has a CAD program for designing a building. The heat loss amount calculation device 30 is provided, for example, in a building manufacturer and is used by a designer of the same manufacturer. The heat loss amount calculation device 30 includes a control unit 31, an operation unit 32, a display unit 33, and a storage unit 34.

[0024] The control unit 31 performs a heat loss amount calculation process for calculating the heat loss amount in the roof part 13. The operation unit 32 performs various operations necessary for the calculation process, and is configured to have a keyboard, a mouse, and the like. The display unit 33 displays various information such as the result of the heat loss amount calculation process, and is composed of a display. Further, the storage unit 34 stores various information necessary for the heat loss amount calculation process.

[0025] Subsequently, the flow of the heat loss amount calculation process performed by the heat loss amount calculation device 30 will be described with reference to FIG. 4. FIG. 4 is a functional block diagram showing the flow of the heat loss amount calculation process. Each block 41 to 45, 47 to 49 in FIG. 4 is realized by the control unit 31. Further, hereinafter, it is assumed that the heat loss amount calculation process is performed on the building 10 described above, and it is assumed that the design data (CAD data) of the building 10 is stored in advance in the storage unit 34 of the heat loss amount calculation device 30.

[0026] As shown in FIG. 4, the design data acquisition unit 41 reads and acquires the design data of the building 10 from the storage unit 34. In this case, the design data of the building 10 acquired by the design data acquisition unit 41 includes the design data of the roof part 13.

[0027] The roof area calculation unit 42 calculates the area S of the roof part 13 based on the design data of the building 10 acquired by the design data acquisition unit 41, specifically, the design data of the roof part 13. Note that the roof area calculation unit 42 corresponds to the outer skin area calculation means.

[0028] The ceiling beam length calculation unit 43 calculates the lengths of all the ceiling beams 22A that form the thermal bridge part in the roof part 13 based on the design data of the roof part 13 acquired by the design data acquisition unit 41.

[0029] The total ceiling beam length calculation unit 44 calculates the total length Lt of those ceiling beams 22A by summing up the lengths of all the ceiling beams 22A calculated by the ceiling beam length calculation unit 43. Note that the ceiling beam length calculation unit 43 and the total ceiling beam length calculation unit 44 constitute the total length calculation means.

[0030] Based on the area S of the roof part 13 calculated by the roof area calculation unit 42 and the total length Lt of the ceiling girders 22A calculated by the total length calculation unit 44 of the ceiling girders, the heat bridge pitch calculation unit 45 calculates a heat bridge pitch P (corresponding to the heat bridge ratio) indicating the ratio of the area occupied by the ceiling girders 22A in the roof part 13. In other words, the heat bridge pitch P indicates the ratio of the area occupied by the heat bridge part in the roof part 13. Note that the heat bridge pitch calculation unit 45 corresponds to the heat bridge ratio calculation means.

[0031] In the heat bridge pitch calculation unit 45, the heat bridge pitch P is calculated by dividing the area S of the roof part 13 by the total length Lt of the ceiling girders 22A (P = S / Lt). In this case, as shown in FIG. 5, the heat bridge pitch P is assumed to be composed of n ceiling girders H of equal length La and the total length is the same as the total length Lt of the ceiling girders 22A. And assuming a rectangular roof part Y with one side length equal to the length La of the ceiling girder H and the area equal to the area S of the roof part 13, when the n ceiling girders H are arranged at equal intervals (equal pitch) in the direction perpendicular to the above side in the roof part Y, it corresponds to the pitch of the ceiling girder H.

[0032] The heat bridge pitch P of the roof part 13 has a correlation with the heat transfer coefficient U of the roof part 13. When the heat bridge pitch P of the roof part 13 is small, the proportion of the ceiling girders 22A (in other words, the heat bridge part) in the roof part 13 becomes large, so heat is easily transferred between the inside and outside of the house through the roof part 13. Therefore, in this case, the heat transfer coefficient U of the roof part 13 becomes large. On the other hand, when the heat bridge pitch P of the roof part 13 is large, the proportion of the ceiling girders 22A in the roof part 13 becomes small, so heat is less likely to be transferred between the inside and outside of the house through the roof part 13. Therefore, in this case, the heat transfer coefficient U of the roof part 13 becomes small. Note that the heat transfer coefficient U of the roof part 13 corresponds to the value obtained by dividing the heat loss amount Q in the roof part 13 by the area S of the roof part 13.

[0033] The correspondence relationship between the heat bridge pitch P and the heat transfer coefficient U in the roof part 13 has been obtained in advance by the building manufacturer, and the obtained correspondence relationship is stored in the heat transfer coefficient database 46. Specifically, for each heat bridge pitch P assumed in the roof part 13 manufactured by the building manufacturer, the heat transfer coefficient U corresponding to the heat bridge pitch P has been obtained in advance, and the heat transfer coefficient U for each heat bridge pitch P is stored in the heat transfer coefficient database 46 as the above correspondence relationship. Note that the heat transfer coefficient database 46 is constructed by the storage unit 34 and corresponds to the storage means.

[0034] Based on the heat bridge pitch P calculated by the heat bridge pitch calculation unit 45 and the above correspondence relationship stored in the heat transfer coefficient database 46, the heat transfer coefficient calculation unit 47 calculates the heat transfer coefficient U of the roof part 13. Specifically, in the heat transfer coefficient calculation unit 47, the heat transfer coefficient U corresponding to the heat bridge pitch P calculated by the heat bridge pitch calculation unit 45 is calculated (extracted) by referring to the above correspondence relationship in the heat transfer coefficient database 46. Note that the heat transfer coefficient calculation unit 47 corresponds to the heat transfer coefficient calculation means.

[0035] Based on the heat transfer coefficient U of the roof part 13 calculated by the heat transfer coefficient calculation unit 47 and the area S of the roof part 13 calculated by the roof area calculation unit 42, the heat loss amount calculation unit 48 calculates the heat loss amount Q in the roof part 13. Specifically, in the heat loss amount calculation unit 48, the heat loss amount Q of the roof part 13 is calculated by multiplying the heat transfer coefficient U of the roof part 13 by the area S of the roof part 13. Note that the heat loss amount calculation unit 48 corresponds to the heat loss amount calculation means.

[0036] The output unit 49 outputs the heat loss amount Q of the roof part 13 calculated by the heat loss amount calculation unit 48 to the display unit 33. As a result, the heat loss amount Q of the roof part 13 is displayed on the display unit 33. Note that instead of or in addition to outputting the heat loss amount Q of the roof part 13 to the display unit 33, the output unit 49 may output the heat loss amount Q of the roof part 13 to an output destination other than the display unit 33, such as a printer.

[0037] According to the configuration of the present embodiment described in detail above, the following excellent effects can be obtained.

[0038] Based on the design data of the unit building 10, the area of the roof part 13 of the building 10 is calculated, and the total length Lt obtained by summing up the lengths of all the ceiling girders 22A in the roof part 13 is calculated. Then, based on the calculated area S of the roof part 13 and the total length Lt of the ceiling girders 22A, a heat bridge pitch P indicating the ratio of the area occupied by the ceiling girders 22A in the roof part 13 is calculated. In the heat transfer coefficient database 46, the correspondence between the heat bridge pitch P in the roof part 13 and the heat transfer coefficient U is stored in advance. Then, based on the calculated heat bridge pitch P and the above-mentioned correspondence stored in the heat transfer coefficient database 46, the heat transfer coefficient U of the roof part 13 is calculated, and based on the calculated heat transfer coefficient U and the calculated area S of the roof part 13, the heat loss amount Q in the roof part 13 is calculated.

[0039] In such a flow of calculating the heat loss amount, the heat loss amount of the roof part 13 is calculated by regarding each of the opposing ceiling girders 22A of the adjacent building units 20 as one heat bridge part. Therefore, unlike the case of calculating the heat loss amount using a heat bridge model including two opposing ceiling girders 22A, it is not necessary to deliberately prepare a heat bridge model for each interval between the opposing ceiling girders 22A. Further, since there is only one pattern as the heat bridge model (that is, only the pattern of one ceiling girder 22A), the process of calculating the heat loss amount is not so complicated, and as a result, it becomes possible to easily calculate the heat loss amount.

[0040] The unit building 10 includes a small interval part 14 where the interval between adjacent building units 20 is small and a large interval part 15 where the interval is large. That is, it includes a part where the interval between the opposing ceiling girders 22A of adjacent building units 20 is small and a part where the interval is large. Even in such a building 10, as described above, since the heat loss amount can be calculated with only one pattern as the heat bridge model, the heat loss amount can be easily calculated.

[0041] The present invention is not limited to the above-described embodiment, and may be implemented, for example, as follows.

[0042] · In the above embodiment, the present invention is applied when calculating the heat loss amount in the roof part 13 of the building 10. However, the present invention may also be applied when calculating the heat loss amount in the floor part (corresponding to the outer skin part) of the first floor of the building 10. In this case, among the floor girders 23 included in the first floor, the opposing floor girders 23 (hereinafter referred to as floor girder 23A) of adjacent building units 20 form a heat bridge part in the first floor. Therefore, the floor girder 23A corresponds to the heat bridge structure material.

[0043] In this case, by replacing the "roof part 13" in the above embodiment with the "first floor" and the "ceiling girder 22A" with the "floor girder 23A", the heat loss amount in the first floor can be calculated in the same procedure as in the above embodiment. · The present invention may also be applied when calculating the heat loss amount in the outer wall part (corresponding to the outer skin part) of the building 10. In this case, among the columns 21, ceiling girders 22, and floor girders 23 included in the outer wall part, the columns 21 (hereinafter referred to as column 21B) facing each other in adjacent building units 20, and the ceiling girders 22 (hereinafter referred to as ceiling girder 22B) and floor girders 23 (hereinafter referred to as floor girder 23B) facing each other in vertically adjacent building units 20 form a heat bridge part in the outer wall part. Therefore, the column 21A, ceiling girder 22B, and floor girder 23B correspond to the heat bridge structure material.

[0044] In this case, by replacing the "roof part 13" in the above embodiment with the "outer wall part" and the "ceiling girder 22A" with the "column 21B, ceiling girder 22B, and floor girder 23B", the heat loss amount in the outer wall part can be calculated in the same procedure as in the above embodiment.

Explanation of reference numerals

[0045] 10…Building, 13…Roof part as the outer skin part, 20…Building unit, 22…Ceiling girder as the structural material, 22A…Ceiling girder as the thermal bridge structural material, 30…Heat loss amount calculation device as the heat loss amount calculation system, 31…Control unit, 42…Roof area calculation unit as the outer skin area calculation means, 45…Thermal bridge pitch calculation unit as the thermal bridge ratio calculation means, 46…Thermal transmittance rate database as the storage means, 47…Thermal transmittance rate calculation unit as the thermal transmittance rate calculation means, 48…Heat loss amount calculation unit as the heat loss amount calculation means.

Claims

1. In a unit-type building constructed by combining a plurality of building units each including a frame body in which columns and beams as structural members are connected in a rectangular parallelepiped shape, a heat loss amount calculation system that targets an outer skin portion which is any one of the roof portion, floor portion, and outer wall portion of the building and calculates the heat loss amount in the outer skin portion, comprising: an outer skin area calculation means for calculating the area of the outer skin portion based on the design data of the building; among the structural members included in the outer skin portion, the opposing structural members of adjacent building units constitute heat bridge structural members that form heat bridges, and a total length calculation means for calculating the total length obtained by summing the lengths of all the heat bridge structural members in the outer skin portion based on the design data of the building; a heat bridge ratio calculation means for calculating a heat bridge ratio indicating the ratio of the area occupied by the heat bridge structural members in the outer skin portion based on the area of the outer skin portion calculated by the outer skin area calculation means and the total length of the heat bridge structural members calculated by the total length calculation means; a storage means in which the correspondence between the heat bridge ratio and the heat transfer coefficient in the outer skin portion is stored in advance; a heat transfer coefficient calculation means for calculating the heat transfer coefficient of the outer skin portion based on the heat bridge ratio calculated by the heat bridge ratio calculation means and the correspondence stored in the storage means; a heat loss amount calculation means for calculating the heat loss amount in the outer skin portion based on the heat transfer coefficient of the outer skin portion calculated by the heat transfer coefficient calculation means and the area of the outer skin portion calculated by the outer skin area calculation means; A heat loss amount calculation system comprising the above.

2. The heat loss amount calculation system according to claim 1, wherein the building includes a small interval portion where the interval between adjacent building units is small and a large interval portion where the interval between adjacent building units is large.

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