Radiation heat measuring device and method thereof

Abstract

To detect the effects of radiant heat from walls.SOLUTION: A radiation heat measuring device comprises a mesh 11, 12, 13, 14 having a plurality of panel materials corresponding to a plurality of the six faces forming a rectangular parallelepiped, planar black bodies 21, 22, 23, 24 arranged on each panel material, thermocouples 31, 32, 33, 34 for measuring the temperatures of the planar black bodies 21, 22, 23, 24, and a measurement circuit 150 for measuring the temperatures of the thermocouples 31, 32, 33, 34, and the plurality of panel materials have air passage holes through which air flows. The planar black bodies 21, 22, 23, 24 are made of resin, and the thermocouples 31, 32, 33, 34 are disposed on the surfaces of the resin, on the outer surfaces of the meshes 11, 12, 13, 14.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a radiation heat measuring device and a method for measuring radiation heat, and more particularly to a radiation heat measuring device for measuring radiation heat radiated from, for example, a wall or ceiling of a room. [Background technology]

[0002] In order to evaluate a living environment, it is necessary to not only measure the indoor temperature but also to evaluate the radiant energy emitted from walls, ceilings, windows, etc. Patent Document 1 discloses an environmental radiation flux meter that measures the radiation flux received by each face of a cube. Patent Document 2 discloses a device that applies black body paint to the inner wall surface and measures the temperature with a radiation thermometer using a measurement hole. Patent Document 3 discloses a temperature measuring device that includes a black body plate with a thermocouple attached and a correction radiation thermometer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP-A-11-173911 (Fig. 11, paragraph 0012) [Patent Document 2] JP 4-91919 A ​​(Claim 2) [Patent Document 3] JP 2015-102508 A (Abstract) Summary of the Invention [Problem to be solved by the invention]

[0004] In the environmental radiometer described in Patent Document 1, the substrates forming each face of the cube (three-dimensional substrate) are made of aluminum plates. Therefore, the temperature of each face is thermally conducted to the air inside the cube. As a result, there is a problem that the internal temperature of the device becomes higher than the room temperature.

[0005] The present invention has been made in consideration of the above circumstances, and has an object to provide a radiation heat measuring device and a radiation heat measuring method that can prevent an increase in the internal temperature of the device. [Means for solving the problem]

[0006] In order to achieve the above object, the radiation heat measuring device of the present invention comprises a housing (mesh 11, 12, 13, 14) having a plurality of surface materials corresponding to a plurality of faces among the six faces forming a rectangular parallelepiped (including a cube), a planar black body (21, 22, 23, 24) arranged on the surface materials, and a temperature sensor (thermocouple 31, 32, 33, 34) for measuring the temperature of the planar black body, and at least one of the plurality of surface materials has a ventilation hole through which air flows. Note that the symbols and letters in parentheses are symbols and the like added in the embodiment and do not limit the present invention. Effect of the Invention

[0007] According to the present invention, the effect of radiant heat absorbed by a wall surface can be detected. [Brief description of the drawings]

[0008] [Figure 1] 1 is an external view of a radiation heat measuring device according to a first embodiment of the present invention. [Diagram 2] 1 is a plan view of a radiation heat measuring device according to a first embodiment of the present invention. [Diagram 3] FIG. 1 is a diagram showing an arrangement state of a radiation heat measuring device according to a first embodiment of the present invention. [Figure 4] FIG. 13 is a diagram showing temperature changes affected by radiant heat emitted from wall and window surfaces. [Diagram 5] FIG. 11 is a diagram for comparing the thermocouple temperature due to ceiling radiation with the ceiling temperature in the radiant heat measuring method of the second embodiment of the present invention, and shows the temperature when there is no radiation shielding sheet. [Figure 6]FIG. 11 is a diagram for comparing the thermocouple temperature due to ceiling radiation with the ceiling temperature in the radiant heat measuring method of the second embodiment of the present invention, and shows the temperature when a radiation shielding sheet is installed on the ceiling. [Figure 7] FIG. 11 is a diagram for comparing the thermocouple temperature due to south-side radiation with the south-side window temperature in the radiant heat measuring method according to the second embodiment of the present invention, and shows the temperature when there is no radiation shielding sheet. [Figure 8] FIG. 11 is a diagram for comparing the thermocouple temperature due to south-side radiation with the south-side window temperature in the radiant heat measuring method of the second embodiment of the present invention, and shows the temperature when a radiation shielding sheet is installed on the south-side window. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention (hereinafter, referred to as "the present embodiment") will be described in detail with reference to the drawings. Note that each drawing is merely a schematic illustration to allow a sufficient understanding of the present embodiment. In addition, in each drawing, common or similar components are given the same reference numerals, and duplicated explanations thereof will be omitted.

[0010] Fig. 1 is an external view of a radiation heat measuring device according to a first embodiment of the present invention, and Fig. 2 is a plan view thereof. Note that a side view and a front view are also similar to Fig. 2. The radiation heat measuring device 100 is configured to include nets 11, 12, 13, 14 as a housing, flat black bodies 21, 22, 23, 24, and thermocouples 31, 32, 33, 34 as temperature sensors. The nets 11, 12, 13, 14 are surface materials that form the walls of the housing, and are arranged along a plurality of faces (for example, a total of four faces, including the top face, front face, and both side faces) out of six faces that form a cube. The flat black bodies are arranged in the center of the nets 11, 12, 13, 14. The bottom face and the rear face of the radiation heat measuring device 100 are open. The radiation heat measuring device 100 is not limited to a cube, and may be a rectangular parallelepiped. The net may be rectangular, and the flat black body may be rectangular or circular.

[0011] The nets 11, 12, 13, and 14 are made of resin with many ventilation holes formed therein. The nets 11, 12, 13, and 14 are made of resin because of ease of processing, but they may be made of metal. For example, the planar black bodies 21, 22, 23, and 24 are not limited to black resin plates, but may be aluminum alloy plates that are black anodized. If the walls of the housing are made of the nets 11, 12, 13, and 14, heat is less likely to be trapped inside the device. In other words, the air flows from the bottom to the top through the many ventilation holes. In addition, black is more preferable than white for the nets 11, 12, 13, and 14. If the net is black, the area of ​​the black body is substantially increased, resulting in an increase in absorbed energy. As a result, the temperature difference due to the presence or absence of radiant heat increases due to heat conduction through the net and black body. In addition, the flat black bodies 21, 22, 23, and 24 are resin plates and are disposed in the center of the outer surface of each of the nets 11, 12, 13, and 14. Note that the nets 11, 12, 13, and 14 may have an opening in the center where the flat black bodies 21, 22, 23, and 24 are disposed.

[0012] Thermocouples 31, 32, 33, and 34 are attached to the center of the outer surface of each resin of flat black bodies 21, 22, 23, and 24. Measurement circuit 150 is connected to thermocouples 31, 32, 33, and 34 (see FIG. 3), and simultaneously measures the surface temperatures of flat black bodies 21, 22, 23, and 24 and records the time changes of these surface temperatures. Note that the temperature sensors may be resistance temperature detectors or thermistors instead of thermocouples 31, 32, 33, and 34.

[0013] FIG. 3 is a diagram showing an arrangement of a radiation heat measuring device according to the first embodiment of the present invention. The radiation heat measuring device 100 and the measurement circuit 150 are disposed on the upper surface of a mounting stand 160 disposed near the north side of the room. The room is a space (e.g., a closed space) configured with a plurality of walls (ceiling 201, east wall 202, south wall 203, north wall 204, floor 205) and one or more windows (south window glass 213, north window glass 214). A door 222 is disposed near the north side of the east wall 202. An air conditioner 224 is disposed at the upper east side of the north wall 204. The measurement circuit 150 is disposed near the radiation heat measuring device 100.

[0014] A number of wall surfaces (ceiling 201, east wall 202, south wall 203, north wall 204, floor 205), window surfaces (south window glass 213, north window glass 214), door 222, etc. radiate heat according to the Stefan-Boltzmann law. In other words, when the emissivity of the wall surface or window surface is ε and the surface temperature of the wall surface or window surface is T [K], the total radiant energy E radiated from the wall surface or window surface per unit area per unit time is expressed as follows: E = 5.67ε(T / 100) 4 [W / m 2 ] It is expressed as:

[0015] The radiation heat measuring device 100 is disposed so that each surface (surfaces of the meshes 11, 12, 13, 14 and the flat black bodies 21, 22, 23, 24) is parallel to the wall surfaces (ceiling 201, east wall 202, south wall 203, north wall 204, floor 205) and window surfaces (south window glass 213, north window glass 214). The wall surfaces (ceiling 201, east wall 202, south wall 203, north wall 204, floor 205) and window surfaces (south window glass 213, north window glass 214) radiate radiation energy E according to their surface temperature and emissivity ε1. The flat black bodies 21, 22, 23, 24 (FIG. 1) absorb the radiation energy E radiated from the wall surfaces and window surfaces according to the form factor P and absorptivity α2. Here, the emissivity ε1 depends on the material and color of the wall and window surfaces, but the absorptivity α2 is a fixed value if the flat black bodies 21, 22, 23, and 24 are made of the same material.

[0016] Here, the shape factor P is complicated, but the temperature measured by the thermocouples 31, 32, 33, 34 is the temperature affected by the radiant heat radiated from the wall surfaces (ceiling 201, east wall 202, south wall 203, north wall 204, floor 205) on the top surface temperature (desk temperature) of the mounting table 160. Here, the top surface temperature is the temperature of the thermocouples 31, 32, 33, 34 when the flat black bodies 21, 22, 23, 24 are not present. According to Kirchhoff's law, the emissivity ε and absorptivity α of an object are equal, and ε1=α1, ε2=α2. Here, α1 is the absorptivity of the wall surface or window surface, and ε2 is the emissivity of the flat black bodies 21, 22, 23, 24.

[0017] FIG. 4 is a diagram showing temperature changes affected by radiant heat radiated from wall and window surfaces. The horizontal axis indicates time, and the vertical axis indicates temperature [°C]. In FIG. 4, a thick dashed black square (■) indicates the temperature of the thermocouple 31 (FIG. 1) affected by ceiling radiation radiated by the ceiling 201 (FIG. 3). A thin dashed black circle (●) indicates the temperature of the thermocouple 32 (FIG. 1) affected by east-side radiation radiated by the east wall 202. A thin dotted black diamond (◆) indicates the temperature of the thermocouple 33 (FIG. 1) affected by south-side radiation radiated by the south wall 203 and the south window glass 213. A thick solid black diamond (◆) indicates the temperature of the thermocouple 34 (FIG. 1) affected by north-side radiation radiated by the north wall 204 and the north window glass 214. A thin solid cross (×) indicates the upper surface temperature (desk temperature) of the mounting table 160.

[0018] The temperature of the thermocouple 34 (Fig. 1) affected by north radiation (thick solid line ◆) is the highest, followed by the thermocouple temperature due to ceiling radiation (■) or south radiation (thin dotted line ◆). The reason the temperature of the thermocouple 34 (Fig. 1) affected by north radiation (thick solid line ◆) is the highest is because the radiation heat measuring device 100 is positioned closer to the north (see Fig. 3). Also, the thermocouple temperature due to east radiation (thick dashed line ●) is the lowest. Note that the thermocouple temperatures due to each type of radiation are higher than the desk temperature (x).

[0019] As described above, the radiant heat measuring device 100 of this embodiment can measure the temperature affected by the radiant heat (radiant energy) from each wall surface on the indoor temperature (desk temperature (x)). The influence of this radiant heat means the temperature difference between the temperature measured by any one of the thermocouples 31, 32, 33, 34 and the temperature measured by the other thermocouples. The influence of this radiant heat also takes into account the distance between each wall surface and the flat black body 21, 22, 23, 24. Furthermore, by simultaneously measuring the temperatures of the thermocouples 31, 32, 33, 34, the measurer can qualitatively grasp temperature characteristics such as "the south window glass is hot" or "the high temperature of the ceiling surface does not decrease." The measurer can also grasp how much radiant heat the human body receives from each wall surface.

[0020] Second embodiment In the radiant heat measuring method of the first embodiment, the radiant heat measuring device 100 measures the temperature affected by the radiant heat radiated from a wall surface, a window surface, etc. In this embodiment, the effect of the radiant heat is measured in a state where a radiation shielding sheet (for example, an aluminum sheet with low emissivity) is attached to the ceiling, window surface, etc. in the same room.

[0021] Figures 5 and 6 are diagrams for comparing the thermocouple temperature due to ceiling radiation with the ceiling temperature. The thick dashed black square (■) indicates the temperature of thermocouple 31 (Figure 1) due to ceiling radiation, and the dot-dash black triangle (▲) indicates the ceiling temperature. Additionally, the thin solid cross (×) indicates the desk temperature. In particular, Figure 5 shows the temperature when there is no radiation shielding sheet, and Figure 6 shows the temperature when a radiation shielding sheet is installed on the ceiling.

[0022] When there is no radiation shielding sheet (Fig. 5), the temperature of thermocouple 31 (Fig. 1) due to ceiling radiation (■) is higher than the desk temperature (×). On the other hand, when there is a radiation shielding sheet (Fig. 6), the temperature of thermocouple 31 due to ceiling radiation (■) decreases and approaches the desk temperature (×).

[0023] Figures 7 and 8 are diagrams for comparing the thermocouple temperature due to south-side radiation and the south-side window temperature. The thin dotted black diamond (◆) indicates the temperature of thermocouple 33 (Figure 1) due to south-side radiation, and the black dashed-dotted square (■) indicates the south-side window temperature. Also, the thin solid cross (×) indicates the desk temperature. In particular, Figure 7 shows the temperature when there is no radiation shielding sheet, and Figure 8 shows the temperature when a radiation shielding sheet is installed on the south-side window.

[0024] When there is no radiation shielding sheet (Fig. 7), the temperature of thermocouple 33 due to south radiation (◆) is higher than the desk temperature (×) due to the influence of the south window temperature (■). On the other hand, when there is a radiation shielding sheet (Fig. 8), the south window temperature (■), which should be high, is affected by the radiation shielding sheet, and the temperature of thermocouple 33 due to south radiation (◆) approaches the desk temperature (×).

[0025] As described above, the radiant heat measuring method of this embodiment makes it possible to determine whether or not to install additional radiation shielding sheets on wall surfaces or window surfaces.

[0026] (Reference example) (1) The black ball measures the average radiation temperature by measuring the temperature inside the black ball, which receives radiant heat from all directions. Since it is the average radiation temperature, it is not possible to determine which wall surface the heat is radiating from. JIS B 7522 defines the black ball temperature as "the temperature (°C) at the center of a hollow black sphere with a diameter of 150 mm and an average emissivity of 0.95 (matte) in the environment around the human body." (2) Thermo cameras are effective in grasping temperature distribution. However, it is not possible to define the emissivity for each material. Therefore, emissivity is generally set to about ε = 0.95, and for materials with low emissivity, the temperature is displayed as low. (3) A radiation thermometer is a thermometer that focuses on a single sensor such as a thermopile to measure radiant heat. Therefore, radiation thermometers are effective for determining local surface temperatures. However, like thermal cameras, the emissivity is set uniformly. Therefore, it is necessary to change the emissivity each time for the target material. In addition, it is possible to find the emissivity that matches the surface temperature found by a thermocouple, making it easy to find the emissivity of a material (see JIS A 1423). (4) Thermocouples are the most accurate because they measure surface temperature directly, however they tend to be interfered with by the surrounding air temperature.

[0027] (Modification) The present invention is not limited to the above-described embodiment, and various modifications are possible, for example, as follows. (1) In the radiation heat measuring device 100 of each of the above embodiments, the meshes 11, 12, 13, 14 are made of resin black bodies, but they may be made of black anodized aluminum plates. When the flat black bodies 21, 22, 23, 24 are made of metal plates such as aluminum plates, they may be disposed on the surface of the metal plate on the inner surface side of the rectangular parallelepiped. (2) In the radiation heat measuring device 100 of each of the above embodiments, the meshes 11, 12, 13, and 14 are used as the surface materials constituting the housing, but a fence may also be used, since the fence has many air holes, just like the mesh.

[0028] (3) In the radiation heat measuring device 100 of each of the above embodiments, four of the six faces forming a cube are provided with meshes 11, 12, 13, and 14 having a large number of air holes, but only one face may be provided. In other words, the other faces (five faces including the bottom face and the face facing the west wall) may be made of flat plates (resin flat plates or metal flat plates) instead of mesh. In this case, since the ceiling face becomes hot, it is preferable to make the face facing the ceiling 201 into a mesh. Also, it is preferable to make two or more faces into a mesh to improve air flow. (4) In the radiant heat measurement method of each of the above embodiments, a mesh, flat black body, or thermocouple is not provided on the bottom surface or one of the side surfaces (west wall), but these may be provided on the one side surface (west wall) or on both the bottom surface and one of the side surfaces (west wall)). [Explanation of symbols]

[0029] 11, 12, 13, 14 Mesh (housing, surface material) 21,22,23,24 Planar blackbody 31, 32, 33, 34 Thermocouple 100 Radiation heat measuring device 150 Measurement circuit 201 Ceiling 202 East Wall 203 South Wall 204 North Wall 205 beds 213 South Window Glass 214 North Window Glass 222 Door 224 Air Conditioner

Claims

1. A housing having a plurality of surface members corresponding to a plurality of surfaces among six surfaces forming a rectangular parallelepiped; A planar black body disposed on the surface material; a temperature sensor for measuring the temperature of the planar blackbody; having At least one of the plurality of face materials has a ventilation hole through which air flows. A radiation heat measuring device characterized by:

2. At least one of the plurality of face materials is formed of a net, The planar black body is disposed in the center of the net.

2. The radiation heat measuring device according to claim 1 .

3. The temperature sensor is disposed on the surface of the flat black body, on the outer surface side of the surface material.

2. The radiation heat measuring device according to claim 1 .

4. The radiation heat measuring device according to any one of claims 1 to 3 is arranged in a room such that each surface material of the housing is approximately parallel to a wall surface of the room, and the temperatures of the plurality of planar black bodies are measured simultaneously by the plurality of temperature sensors. A method for measuring radiant heat.

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