JP7280595B2 - Performance change prediction system and program for vacuum insulation materials - Google Patents

Description

The present invention obtains measurement data from long-term internal pressure measurement of vacuum insulation materials used for exterior walls of houses and plants, etc., and uses the measurement data for a certain period to express long-term performance changes in thermal conductivity and internal pressure. A system and program that calculates an evaluation value and predicts changes in insulation performance after several years of vacuum insulation installed on the outer wall of a house or plant based on the performance evaluation value (hereinafter referred to as "insulation performance change prediction system, etc. ”). Specifically, the present invention relates to a vacuum insulation performance change prediction system suitable for notifying customers, construction companies, etc. of the current insulation performance and replacement timing of vacuum insulation materials by alerts or the like.

Vacuum insulation materials are widely used in various fields such as refrigerators, thermos flasks, outer walls of houses and plants, etc., as insulation materials with higher insulation performance than styrofoam. This vacuum insulation material is produced, for example, by covering a porous core material having many voids inside with a bag-shaped gas barrier film that encloses the core material, reducing the pressure, and heat-sealing the openings of the gas barrier film ( heat sealing), and an outer layer is provided on the outside of the gas barrier film.

In general, vacuum insulation materials installed on the outer walls of houses and plants deteriorate over time as they are used for a long period of time. The heat insulation performance is lowered due to the inflow of For this reason, there has been proposed a device or the like in which a temperature sensor, a vacuum sensor, or the like is provided in the vacuum insulation material to monitor the performance of the vacuum insulation material over a long period of time and detect changes in the performance of the vacuum insulation material. .

For example, in the vacuum insulation panel described in Japanese Patent No. 4641565 (Patent Document 1), a core material is covered with a gas barrier outer skin material, a temperature sensor unit capable of measuring the ambient temperature, and the measurement result of the temperature sensor unit are collected. A communication unit capable of wireless communication and a battery are arranged inside the outer skin material. In addition, the vacuum insulation panel described in Japanese Patent Application Laid-Open No. 2012-136254 (Patent Document 2) is a heat insulation panel in which a heat insulating material is covered with a gas barrier film and the inside is evacuated, at least a vacuum sensor inside the outer skin material, A communication unit capable of transmitting the vacuum data detected by the vacuum sensor to the outside and a battery are provided.

These conventional vacuum insulation panels (vacuum insulation panels) can measure the degree of vacuum of the vacuum insulation materials and the ambient temperature by built-in sensors, and transmit the measured data to external devices by wireless communication. The heat insulating performance of the vacuum heat insulating material can be monitored by the external device that receives the measurement data. As a result, a customer, a contractor, or the like who uses the external device can know the performance of the vacuum insulation material at the time of measurement by the sensor.

Japanese Patent No. 4641565 JP 2012-136254 A

However, in the monitoring of the vacuum insulation material according to the above-described conventional example, it is simply determined whether the insulation performance of the vacuum insulation material at the time of measurement has deteriorated based on various measurement values such as temperature and vacuum (internal pressure) obtained from the sensor. However, it is difficult to predict changes in the insulation performance of the vacuum insulation material after a few years by considering changes in measured values obtained from the vacuum insulation material in a time series manner.

Therefore, in the present invention, the measurement data is periodically acquired from the built-in sensor of the vacuum insulation material, stored in a storage device in chronological order together with the measurement date, and the internal pressure value (internal pressure value) is calculated from the stored measurement data. The difference between the latest internal pressure value and the past internal pressure value is calculated, and the measurement interval of the measurement data corresponding to those internal pressure values (for example, the date when the latest measurement data was accumulated and the past measurement data was accumulated) By dividing by the number of days, which is the difference from the day, to calculate the pressure gradient, which is an example of the performance evaluation value, the change in the insulation performance of the vacuum insulation material after several years or later based on the calculated pressure gradient It is possible to predict the replacement timing of the vacuum insulation material and present an alert regarding the current insulation performance to those who monitor the long-term change in the insulation performance of the vacuum insulation material (construction contractors, manufacturers, etc.). Provide a thermal insulation performance change prediction system.

As one embodiment of the thermal insulation performance change prediction system according to the present invention, it includes a core material, a gas barrier film covering the core material, and an outer layer provided outside the gas barrier film, and the inside is sealed under reduced pressure. A small wireless vacuum gauge provided inside the outer layer of the vacuum insulation material, the compact wireless vacuum gauge including at least a pressure sensor and a transmission unit for transmitting measurement data measured by the pressure sensor. a storage unit that stores measurement data;
An internal pressure value indicating the internal pressure of the vacuum insulation material at the time of measurement by the pressure sensor is obtained from the measurement data, and an internal pressure difference between the internal pressure value and a past internal pressure value representing the past internal pressure of the vacuum insulation material. and a pressure gradient calculation unit that obtains a pressure gradient value representing the amount of change in the internal pressure difference per unit time;
a performance determination unit that determines the thermal insulation performance of the vacuum insulation material after a specified period of time has elapsed based on the thermal conductivity converted from the pressure gradient value;
a notification unit that notifies according to the determination result of the performance determination unit;
The performance determination unit determines whether the thermal conductivity is equal to or higher than a predetermined thermal conductivity,
The notification unit is characterized in that, when the performance determination unit determines that the thermal conductivity is equal to or higher than the specified thermal conductivity, the notification unit issues a notification to prompt replacement of the vacuum heat insulating material.

A preferred embodiment of the thermal insulation performance change prediction system according to the present invention is characterized in that the pressure gradient value is calculated by Equation (1) described later.

A preferred embodiment of the thermal insulation performance change prediction system according to the present invention is characterized in that the thermal conductivity is calculated by Equation (2) described later.

A preferred embodiment of the thermal insulation performance change prediction system according to the present invention is characterized in that the value t representing the replacement timing in Equation (2) described later is the value of the previously specified specified period.

A preferable embodiment of the thermal insulation performance change prediction system according to the present invention is characterized in that the replacement time is calculated by Equation (3) described later.

A preferred embodiment of the thermal insulation performance change prediction system according to the present invention is characterized in that λ _cop in Equation (3), which will be described later, is the previously specified thermal conductivity value.

As a preferred embodiment of the thermal insulation performance change prediction system according to the present invention, the notification unit notifies the period or time until the thermal conductivity of the vacuum insulation material reaches the specified thermal conductivity. .

As a preferred embodiment of the thermal insulation performance change prediction system according to the present invention, the notification unit reaches the specified thermal conductivity when the performance determination unit determines that the thermal conductivity is less than the specified thermal conductivity. It is characterized by notifying the period or time until it is completed.

As a preferred embodiment of the thermal insulation performance change prediction system according to the present invention, the performance determination unit further includes a current value of the thermal conductivity λ _cop and one or more past values obtained in the past by the performance determination unit. Determines whether or not the correlation coefficient of is equal to or greater than a predetermined correlation coefficient,
The notification unit is characterized in that, when the performance determination unit determines that the correlation coefficient is less than the specified correlation coefficient, the notification unit issues a notification prompting replacement of the vacuum insulation material or a warning notification of an abnormality. do.

As a preferred embodiment of the thermal insulation performance change prediction system according to the present invention, the correlation coefficient is calculated by Equation (4) described later, where X is the current value of the thermal conductivity λ _cop and Y is the past value. characterized by being

An embodiment of the insulation performance change prediction program according to the present invention is characterized by causing a computer to function as the insulation performance change prediction system.

A thermal insulation performance change prediction system according to one embodiment of the present invention detects the difference between the latest internal pressure value and the past internal pressure value of the vacuum insulation material by periodical monitoring using the built-in sensor of the vacuum insulation material. Equipped with a pressure gradient calculation unit that calculates the pressure gradient by dividing the number of monitoring days from the latest to the latest. Prediction becomes possible. In addition, the insulation performance change prediction system according to one embodiment of the present invention provides an alert regarding the replacement timing of the vacuum insulation material and the current insulation performance based on the predicted change in insulation performance. It is also possible to present it to a person (construction contractor, manufacturer, etc.) who monitors changes in thermal insulation performance.

It is a figure which shows the system configuration example for monitoring a vacuum insulation material. FIG. 4 is a block diagram showing the component configuration of a small wireless vacuum gauge included in the vacuum insulation material to be monitored; It is a block diagram which shows the structural example of the hardware of the computer which functions as an insulation performance change prediction system. It is a block diagram showing an example of functional composition of a thermal insulation performance change prediction system concerning one embodiment of the present invention. It is a figure which shows an example of the display screen of an insulation performance change prediction system. 4 is a flow chart showing the flow of processing for converting an output value acquired from a pressure sensor in a compact wireless vacuum gauge into a pressure value; 4 is a graph showing the relationship between the pressure sensor in the small wireless vacuum gauge and the internal pressure of the vacuum insulator. 4 is a graph showing the relationship between the thermal conductivity of a vacuum heat insulating material containing a glass wool core material and the internal pressure of the vacuum heat insulating material. FIG. 10 is a graph in which the graphs shown in FIGS. 8 and 9 are superimposed; FIG. 10 is a flow chart showing the flow of processing for determining the heat insulating performance of the vacuum heat insulating material after a specified period has elapsed, based on the thermal conductivity converted from the pressure gradient value. 4 is a graph showing the relationship (pressure gradient) between the internal pressure of the vacuum heat insulating material and the period (days).

An embodiment of the present invention will be described below with reference to the drawings. In principle, the same members are denoted by the same reference numerals in all the drawings for describing the embodiments, and repeated description thereof will be omitted.

FIG. 1 is a diagram showing a configuration example of a system for monitoring vacuum insulation. The compact wireless vacuum gauge 10 is provided in the vacuum insulation material 20, and transmits measurement data for calculating an internal pressure value indicating the internal pressure of the vacuum insulation material 20 to the server 30 via a network N such as the Internet. be able to.

The compact wireless vacuum gauge 10 can transmit measurement data to a mobile terminal (external receiving unit) (not shown) by wireless communication, and the mobile terminal can transmit the measurement data to the server 30 via the network N. . Also, the compact wireless vacuum gauge 10 can be directly connected to a network via Wi-Fi or the like to transmit measurement data to the server 30 preset as a transmission destination of the measurement data. The terminal 40 is connected to the server 30 via the network N, and notifies ( Alerts), etc. can be received and displayed on the screen.

FIG. 2 is a block diagram showing the component configuration of a compact wireless vacuum gauge included in the vacuum insulation material according to one embodiment of the present invention. The compact wireless vacuum gauge 10 includes a pressure sensor 1, an operational amplifier 2, an A/D converter 3, a CPU/wireless transmission unit 4, a temperature/humidity sensor/internal clock 5, a charging unit 6, and a DC/DC converter 7. and a battery 8 .

A pressure sensor 1 measures the pressure inside the vacuum insulation material, and an operational amplifier 2 connected to the pressure sensor 1 can amplify an analog signal of the measured pressure value. The A/D converter 3 connected to the operational amplifier 2 converts the amplified analog signal into a digital signal, and the CPU/radio transmission unit 4 connected to the A/D converter 3 receives the digital signal, The signal can be transmitted as measurement data to an external receiving unit (not shown) by sub-giga band radio below 1 GHz or by 2.4 GHz band radio or by 5 GHz band radio.

The frequency band of the CPU/radio transmission unit 4 can be selected as long as it is a frequency band that allows radio transmission. The 920 MHz band uses the ISM band and consumes a large amount of power per transmission. However, compared to the 2.4 GHz band, the 920 MHz band is more diffractive, so it is possible to communicate around obstacles. is possible.

On the other hand, in the 2.4 GHz band communication method including BLE (Bluetooth Low Energy) communication, power consumption is small, but the reach of radio waves is about 5 cm from the surface of the outer layer of a general vacuum insulation material. It is difficult to measure when the vacuum insulation material is installed inside the wall, but it can be used when the wall thickness is thin or when the surface of the vacuum insulation material is exposed from the wall.

The external receiving unit records the measured voltage when the measured data is received, and can be converted from a known calibration value (voltage/pressure) to a pressure value, and the pressure value output in the conversion is, for example, It is calculated by a program running on the receiving unit (server).

The pressure sensor 1 can use a thermocouple type vacuum sensor formed by a micro-electro-mechanical system (MEMS). Also, the pressure sensor 1 may be a thermocouple type vacuum sensor made of MEMS.

The temperature/humidity sensor/internal clock 5 connected to the CPU/wireless transmission unit 4 can directly transmit a signal to the CPU through serial communication such as I2C communication. The CPU/wireless transmission unit 4 can wirelessly transmit a signal from the temperature/humidity sensor/internal clock 5 to an external reception unit. Even without the temperature and humidity sensor, the pressure sensor 1 can measure the pressure inside the vacuum insulation material. good. That is, a temperature and humidity sensor can be included in the compact wireless vacuum gauge 10 as needed, such as to check for water vapor pressure problems entering the interior of the vacuum insulation. Furthermore, the compact wireless vacuum gauge 10 can also include sensors for measuring various molecular species (carbon dioxide, carbon monoxide, oxygen, VOCs, etc.). That is, the compact wireless vacuum gauge 10 can further include at least one of a temperature sensor, a humidity sensor, sensors for measuring various molecular species, and an internal clock.

A battery 8 connected to the CPU and wireless transmission unit 4 can supply power to the CPU and wireless transmission unit 4 and other components (elements) electrically connected thereto. Also, the battery 8 is connected to the charging unit 6 via the DC/DC converter 7 , and the charging unit 6 can supply power for charging the battery 8 . The DC/DC converter 7 can convert the voltage obtained from the charging unit 6 into the voltage required for charging the battery 8 .

Note that the DC/DC converter 7 is essentially not essential for charging the battery 8 of the compact wireless vacuum gauge 10 . The DC/DC converter 7 is configured to minimize the effect of dielectric loss that may occur due to dielectric heating when charging is performed through the metallic gas barrier film of the vacuum heat insulating material. . In other words, when such dielectric heating is caused, it becomes difficult to supply the required power, so using the DC/DC converter 7 makes it possible to boost the voltage to the required level.

When a higher voltage is applied, heat generation on the surface of the vacuum heat insulating material increases, which may damage the gas barrier film made up of the resin and metal layers or dissolve the resin film. In such a case, the vacuum heat insulating material cannot maintain the vacuum, and the heat insulating property is greatly impaired. Therefore, driving the sensor via the DC/DC converter 7 is a more preferable configuration when operating inside the vacuum heat insulating material.

The charging unit 6 can employ a Peltier element or a coil for contactless power supply as a charging mechanism. When a Peltier element is used as the charging mechanism of the charging unit 6, power generated by the Seebeck effect can be supplied to the battery 8 via the DC/DC converter 7 by applying heat to the Peltier element. . For example, when a small lithium ion polymer (LiPo) battery of 85 mAh is adopted as the battery 8, the charging of the small LiPo battery is completed by applying heat of 80° C. to the Peltier element of the charging unit 6 for about 5 minutes. can do. If heat of 80° C. is applied for about 5 minutes, charging can be performed without causing damage to the vacuum insulation material.

The charging unit 6 can supply power generated by an electromagnetic induction method or a magnetic resonance method to the battery 8 via the DC/DC converter 7 when a coil for contactless power supply is used as the charging mechanism. For example, in the case of the electromagnetic induction method, the charging unit 6 includes a power receiving side coil, and the dielectric flux generated between the power transmitting side coil and the power receiving side coil included in the charger outside the vacuum insulation material is used. The generated power can be received by the charging unit 6 .

In the case of the electric field resonance method, the power receiving side coil is included in the power receiving side resonance circuit, and the power transmission side coil is included in the power transmission side resonance circuit. The vibration of the magnetic field generated by the current flowing through the transmitting coil included in the charger's power transmitting side resonance circuit is transmitted to the receiving side coil included in the power receiving side resonant circuit that resonates at the same frequency, causing magnetic field resonance. The charged power can be received by the charging unit 6 .

A small wireless vacuum gauge 10 is provided inside a vacuum insulation material sealed under reduced pressure. The vacuum insulation material includes a core material, a gas barrier film covering the core material, and an outer layer provided outside the gas barrier film. Preferably, it is contained inside the gas barrier film.

As described above, the compact wireless vacuum gauge 10 is provided with a charging unit including a charging mechanism capable of charging the battery without electrical connection to an external power source, so that the compact wireless vacuum gauge 10 is built in the vacuum insulation material. can continuously supply sufficient power to withstand long-term operation.

As the core material of the vacuum heat insulating material, those used in the vacuum heat insulating material field can be used without particular limitation. Specific examples that can be used include open-cell rigid polyurethane foam, inorganic fibers, organic fibers, inorganic powders, and aerogels. From the viewpoints of handling and heat insulation, sheet-shaped inorganic fibers are preferred. Examples of inorganic fibers include glass fibers, ceramic fibers such as alumina and silica, slag wool fibers, rock wool fibers, and the like. Among these, glass fiber is preferable from the viewpoint of heat insulation, moldability, and the like. In order to improve the heat resistance of the core material, a small amount of heat-resistant metal fibers such as stainless steel, chromium-nickel alloys, high-nickel alloys, and high-cobalt alloys can be mixed. Core materials are known and readily available on the market or can be prepared.

In the vacuum heat insulating material according to one embodiment of the present invention, the adsorbent may be enclosed in a bag-shaped gas barrier film together with the core material. The adsorbent is, for example, a substance that adsorbs gases such as nitrogen, oxygen, carbon dioxide, and/or moisture. Adsorbents include calcium oxide, silica gel, zeolite, activated carbon, barium oxide, barium-lithium alloys, and mixtures thereof. From the viewpoint of gas adsorption performance and productivity, calcium oxide is preferred. Adsorbents are known and readily available on the market or can be prepared.

The gas barrier film used in the present invention is not particularly limited as long as it is a film having gas barrier properties. More preferably, more than one resin film layer is laminated. The thickness of the gas barrier film is not particularly limited, but is usually 50-200 μm, preferably 60-180 μm.

The gas barrier layer is a layer impermeable to gas, and is used from the viewpoint of preventing a decrease in the degree of vacuum of the vacuum heat insulating material. Examples of the gas barrier layer include a metal foil and a vapor-deposited film obtained by forming a vapor-deposited film on a resin film. A vapor deposition film is obtained by forming a vapor deposition film on a substrate by a vapor deposition method, a sputtering method, or the like. From the viewpoint of gas barrier properties and economy, aluminum is preferably used for both the metal foil and the vapor deposition material.

Examples of the resin film that serves as a base material for vapor deposition films include aromatic polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT); polyolefin resins such as polyethylene, polypropylene, and olefin copolymers; Vinyl chloride resins such as vinyl chloride copolymers; polyamide resins such as nylon 6, nylon 66, metaxylylenediamine/adipic acid condensate; styrenes such as acrylonitrile/butadiene/styrene copolymers and acrylonitrile/styrene copolymers -based resin; acrylic resin such as polymethyl methacrylate, acrylic acid ester and methyl methacrylic acid ester copolymer, ethylene-vinyl alcohol copolymer, thermoplastic resin such as partially saponified polyvinyl alcohol and polyvinyl acetate, Films made from thermosetting resins such as phenolic resins and urea resins are used.

The thickness of the gas barrier layer is not particularly limited, but in the case of metal foil, it is 1 to 60 μm, preferably 5 to 30 μm. If the thickness is 1 μm or more, the strength of the metal foil is high, and the formation of pinholes and the like can be suppressed. In the case of a vapor deposited film, the gas barrier layer has a thickness of 10 to 60 μm, preferably 12 to 30 μm, of which the vapor deposited film has a thickness of 0.2 to 3.0 μm, preferably 0.5 to 2.0 μm. is. If the vapor-deposited film has a thickness of 0.2 μm or more, gas barrier properties can be exhibited, and if it is 3.0 μm or less, technical difficulty in forming the vapor-deposited film is not so great. Metal foils and vapor-deposited films used for the gas barrier layer are well known and can be easily obtained on the market or can be prepared.

The seal layer is a resin that can be fused by heating. There is no particular limitation as long as it is a heat-sealable resin. Specifically, films made of polyolefin resins such as polyethylene and polypropylene, polyacrylonitrile, PET, ethylene-vinyl alcohol copolymers, or mixtures thereof can be used. Polyethylene, polypropylene, and ethylene-vinyl alcohol copolymer are preferably used. The polyethylene preferably has a density of 0.90-0.98 g/cm ³ . Polypropylene preferably has a density of 0.85 to 0.95 g/cm ³ . The thickness of the sealing layer is not particularly limited, but is usually 10-100 μm, preferably 25-60 μm. Resins used in sealing layers are well known and readily available on the market or can be prepared.

The resin film layer is a layer optionally provided on the gas barrier layer for the purpose of protecting the gas barrier layer. As the resin film layer, aromatic polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT); polyolefin resins such as polyethylene, polypropylene, and olefin copolymers; polyvinyl chloride, vinyl chloride copolymers, and the like. vinyl chloride resins; polyamide resins such as nylon 6, nylon 66, metaxylylenediamine-adipic acid condensate; polyvinyl alcohol, acrylonitrile-butadiene-styrene copolymer, styrene-based resins such as acrylonitrile-styrene copolymer; Films made from thermoplastic resins such as acrylic resins such as polymethyl methacrylate, acrylate and methyl methacrylate copolymers, etc., and thermosetting resins such as phenol resins and urea resins are used. PET, nylon 6 or nylon 66 is preferred. Organic or inorganic fillers may be added to these resin films. These resins can be used alone or in combination of two or more. In order to further improve the gas barrier performance of the gas barrier film, the resin film layer is coated or laminated with a gas barrier resin obtained by polymerizing or copolymerizing a vinyl monomer such as vinylidene chloride, acrylonitrile, or vinyl alcohol. , the particles can also be mixed and dispersed in the resin film layer. Although the thickness of the resin film layer is not particularly limited, it is usually 5 to 40 μm, preferably 10 to 30 μm. The resins used in the resin film layer are well known and readily available commercially or can be prepared.

A gas barrier film is formed in a bag shape. The bag shape is a shape in which a core material and an adsorbent can be put. There are no particular restrictions on the process of forming the gas barrier film into a bag shape. For example, when the gas barrier film has a seal layer, two sheets of the gas barrier film are stacked so that the seal layers are in contact with each other, and the core material and adsorbent are inserted around the portion where the core material and adsorbent are placed. The gas barrier film may be formed into a bag shape by heat-sealing while leaving an opening for the gas barrier.

Paper and/or non-woven fabric can be laminated on the outer layer of the gas barrier film for vacuum insulation material used in the present invention. Paper is a product made by agglutinating plant fibers and other fibers. Both organic and inorganic fibers can be used as paper material. Organic fibers used as paper materials include, for example, plant-derived fibers and synthetic fibers, and inorganic fibers used as paper materials include, for example, minerals, metal fibers, synthetic fibers, and the like. Nonwovens are fibrous sheets, webs or batts having unidirectional or randomly oriented lines and interfiber bonds by alternating and/or fusion and/or adhesion. Both organic and inorganic fibers can be used as the nonwoven material.

Organic fibers used as materials for non-woven fabrics include natural fibers and chemical fibers. Natural fibers include cotton, wool, felt, hemp, pulp, silk, etc. Chemical fibers include rayon, polyamide, polyester, polypropylene, acrylic fibers, Examples include vinylon, aramid fiber, and acetate. Glass fibers, carbon fibers, mineral fibers, and the like are examples of inorganic fibers used as raw materials for nonwoven fabrics. Preferred materials are polyamide, polyester, polypropylene. Paper and nonwovens are well known and readily available on the market or can be prepared.

The thickness of the outer layer is 0.01 mm to 3 mm, preferably 0.03 to 0.5 mm. Although the basis weight of the outer layer is not particularly limited, it is preferably 10 to 200 g/m ² , more preferably 20 to 100 g/m ² .

The outer layer is adhered to the side of the gas barrier film that is not in contact with the core (outer side of the vacuum heat insulating material), for example, by lamination. Lamination methods include dry lamination, extrusion lamination, hot-melt lamination, wet lamination, and thermal lamination.

The shape of the vacuum heat insulating material is, for example, a plate shape. A plate shape means a thin and flat shape, and has two opposing surfaces and side peripheral surfaces connecting these two surfaces. The outer layer covers part of at least one side of the plate-shaped vacuum heat insulating material, and preferably covers the edge of the side facing the heat source in use in a frame shape. The outer layer preferably covers the side peripheral surfaces of the vacuum heat insulating material, and more preferably covers the entire surface (that is, both sides and the side peripheral surfaces) of the vacuum heat insulating material. Also, when a plurality of vacuum heat insulating materials are used in combination, it is advantageous to cover the side peripheral surface with an outer layer in order to prevent heat leakage at joints between the vacuum heat insulating materials.

FIG. 3 is a block diagram showing a configuration example of computer hardware that functions as a thermal insulation performance change prediction system. In the drawing, the reference numerals corresponding to the hardware of the server 30 are written without parentheses, and the reference numerals corresponding to the hardware of the terminal 40 are written with parentheses.

The server 30 illustratively includes a CPU (Central Processing Unit) 31, a memory 33 including a ROM (Read Only Memory), a RAM (Random Access Memory), etc., a bus 34, an input/output interface 35, and an input unit 36. , an output unit 37 , a storage unit 38 , and a communication unit 39 .

The CPU 31 executes various processes according to programs recorded in the memory 33 or programs loaded from the storage unit 38 to the memory 33 . The CPU 31 can execute, for example, a program for causing the server 30 to function as the thermal insulation performance change prediction system of the present invention. It is also possible to implement at least part of the functions of the thermal insulation performance change prediction system in the form of hardware such as an application specific integrated circuit (ASIC).

The memory 33 also stores data necessary for the CPU 31 to execute various processes. The CPU 31 and memory 33 are interconnected via a bus 34 . An input/output interface 35 is also connected to the bus 34 . An input unit 36 , an output unit 37 , a storage unit 38 and a communication unit 39 are connected to the input/output interface 35 .

The input unit 36 is composed of various buttons, a touch panel, a microphone, or the like, and inputs various kinds of information according to instruction operations of the administrator of the server 30 or the like. Note that the input unit 36 may be realized by an input device such as a keyboard and a mouse that is independent of the main body that accommodates other units of the server 30 .

The output unit 37 is composed of a display, a speaker, etc., and outputs image data and music data. The image data and music data output by the output unit 37 are output from a display, a speaker, or the like so that the player can recognize them as images or music.

The storage unit 38 is composed of a semiconductor memory such as a DRAM (Dynamic Random Access Memory) and stores various data.

The communication unit 39 implements communication with other devices. For example, the communication unit 39 communicates with the terminal 40 via the network N. FIG.

The server 30 is appropriately provided with a drive (not shown) as necessary. Removable media such as magnetic disks, optical disks, magneto-optical disks, or semiconductor memories are installed in the drives as appropriate. The removable media stores a program for executing the game and various data such as image data. Programs and various data such as image data read from the removable media by the drive are installed in the storage unit 38 as necessary.

Next, the hardware configuration of the terminal 40 will be described. Terminal 40, as shown in FIG. and have. Each of these units has the same functions as those of the same-named units provided in the above-described server 30 with different symbols. Therefore, redundant description is omitted. When the terminal 40 is configured as a portable device, each piece of hardware included in the terminal 40, the display, and the speaker may be realized as an integrated device.

(Functional configuration)
FIG. 4 is a block diagram showing an example of a functional configuration of a thermal insulation performance change prediction system according to one embodiment of the present invention. FIG. 4 is a block diagram showing a functional configuration for executing a process such as a thermal insulation performance change prediction process among the functional configurations of the server 30 and the terminal 40 shown in FIG.

Here, the thermal insulation performance change prediction processing refers to the time-series internal pressure value (internal pressure value) obtained by converting the measurement data repeatedly acquired at time intervals from the vacuum insulation material to be monitored. This is a process for predicting long-term changes in the insulation performance of the vacuum insulation material using an index (pressure gradient) based on changes. The specific contents of the processing will be described later with reference to the flowcharts shown in FIGS. 5 and 6. FIG.

When the server 30 executes a program that realizes the heat insulation performance change prediction process, as shown in FIG. In addition, in a partial storage area of the storage unit 38, a measurement data storage unit 381 for storing measurement data acquired from the vacuum insulation material to be monitored, and a value of the internal pressure of the vacuum insulation material (internal pressure value) and an internal pressure value storage unit 382 converted into a value).

Communication with the terminal 40 by the heat insulation performance change prediction process is performed using the communication unit 39 of the server 30 and the communication unit 49 of the terminal 40 . As shown in FIG. 1, there is a network N for realizing communication between the server 30 and the terminal 40, but illustration of this network N is omitted in FIG.

In the measurement data storage unit 381, the pressure sensor 1 (see FIG. 2) obtained from the small wireless vacuum gauge 10 provided for monitoring the internal state of the vacuum insulation material 20 as shown in FIG. Measurement data is stored in association with measurement time. The pressure gradient calculation unit 311 obtains an internal pressure value indicating the internal pressure of the vacuum heat insulating material 20 at the time of measurement by the pressure sensor 1 from the measurement data measured by the pressure sensor 1, and converts the obtained internal pressure value into the measurement data (and/or Alternatively, it can be stored in the internal pressure value storage unit 382 in association with the measurement time).

ただし、ΔPa は、前記圧力勾配値であり、Pa_c は計測時点での前記真空断熱材の前記内圧値であり、Pa_a は Pa_c よりも過去に計測された前記過去内圧値であり、Day は Pa_a の計測時点から Pa_c の計測時点までの測定間隔を表す日数である。 In addition, the pressure gradient calculation unit 311 refers to the internal pressure value storage unit 382, and compares the internal pressure value at a predetermined measurement time and the past internal pressure value representing the internal pressure value of the vacuum insulation material in the past. A difference is calculated to obtain a pressure gradient value representing the amount of change in the internal pressure difference per unit time. The pressure gradient value is calculated by the following formula (1).

However, ΔPa is the pressure gradient value, Pac is the internal pressure value of the vacuum insulation material at the time of measurement, _{Pa a is} the past internal pressure value measured earlier than _Pac , and Day is the number of days between the measurement of _Paa and the measurement of _Pac .

ただし、λ_cop は真空断熱材の中央部の熱伝導率であり、λ_sr は雰囲気圧力である Pa が 1Pa 以下の時の芯材の固体及び放射熱伝導率であり、λ_ga は乾燥空気の熱伝導率であり、P_1/2 は芯材の大気圧下での熱伝導率の値と、真空下（1Pa以下）での熱伝導率の値を足して２で割った熱伝導率の時の雰囲気圧力値、ｔ は、交換時期を表す値である。なお、交換時期を表す値 ｔ は、予め指定された指定期間の値とすることができる。 The performance determination unit 312 can determine the heat insulation performance of the vacuum heat insulating material after a specified period has elapsed based on the thermal conductivity converted from the pressure gradient value. Thermal conductivity is calculated by the following formula (2). Formula (2) requires obtaining λ _{sr ,} λ _ga , and P _1/2 in advance for each material used to manufacture the vacuum insulation material.

However, λ _cop is the thermal conductivity of the central part of the vacuum insulation material, λ _sr is the solid and radiant thermal conductivity of the core material when the atmospheric pressure Pa is 1 Pa or less, and λ _ga is the dry air P _1/2 is the thermal conductivity value obtained by adding the value of thermal conductivity under atmospheric pressure of the core material and the value of thermal conductivity under vacuum (1 Pa or less) and dividing by 2. The atmospheric pressure value at time, t, is a value representing the replacement time. Note that the value t representing the replacement timing can be a value for a specified period specified in advance.

As for the vacuum heat insulating material used in the present invention, it is desirable to understand the relationship between the thermal conductivity and the internal pressure according to Equation (2) before incorporating the sensor into the product. As a method of measurement, the thermal conductivity of the vacuum insulation material incorporating the sensor is measured based on the heat flow meter method (JIS-1412 Part II), and the pressure at that time is used to calculate the relational expression between thermal conductivity and pressure (2). is there a way to get

ただし、ｔ は、交換時期を表す値であり、λ_cop は真空断熱材の中央部の熱伝導率であり、λ_sr は雰囲気圧力である Pa が 1Pa 以下の時の芯材の固体及び放射熱伝導率であり、λ_ga は乾燥空気の熱伝導率であり、P_1/2 は芯材の大気圧下での熱伝導率の値と、真空下（1Pa以下）での熱伝導率の値を足して２で割った熱伝導率の時の雰囲気圧力値である。なお、 λ_cop は、予め指定された指定熱伝導率の値とすることができる。 The replacement time is calculated by the following formula (3).

However, t is a value that represents the replacement time, λ _cop is the thermal conductivity of the central part of the vacuum insulation material, and λ _sr is the atmospheric pressure Pa, which is the solid and radiant heat of the core material when Pa is 1 Pa or less. λ _ga is the thermal conductivity of dry air, P _1/2 is the thermal conductivity value of the core material under atmospheric pressure and the thermal conductivity value under vacuum (1 Pa or less) is the atmospheric pressure value at the time of thermal conductivity obtained by adding and dividing by 2. Note that λ _cop can be a value of a specified thermal conductivity specified in advance.

The notification unit 313 can notify the period or time until the thermal conductivity of the vacuum heat insulating material reaches a specified thermal conductivity specified in advance. In addition, when the performance determination unit 312 determines that the thermal conductivity of the vacuum insulation material is less than the specified thermal conductivity, the notification unit 313 can also notify the period or time until the specified thermal conductivity is reached. . Furthermore, when the performance determination unit 312 determines that the thermal conductivity of the vacuum insulation material exceeds the specified thermal conductivity, the notification unit 313
Alerts can be notified. For example, the notification unit 313 informs the output unit 47 such as the monitor of the terminal 40 via the communication unit 39 according to the determination result of the performance determination unit 312 that the thermal conductivity of the vacuum insulation material reaches the specified thermal conductivity. It is possible to display the period or time until the end of the period as a prediction result, display an alert notifying of deterioration of the insulation performance, and the like.

The performance determination unit 312 further determines that the correlation coefficient between the current value of the thermal conductivity λ _cop calculated by the above-described formula (2) and one or more past values obtained in the past by the performance determination unit 312 is It can be determined whether or not the correlation coefficient is equal to or greater than a specified correlation coefficient specified in advance. The correlation coefficient is calculated by the following formula (4), where X is the current value of the thermal conductivity λ _cop and Y is the past value.

When the performance determination unit 312 determines that the correlation coefficient is less than a predetermined correlation coefficient, the notification unit 313 can issue a notification prompting replacement of the vacuum insulation material or a warning notification of an abnormality. .

The terminal 40 can display a display screen as shown in FIG. FIG. 5 is a diagram showing an example of a display screen of the insulation performance change prediction system. For example, in the calibration result substitution column, various parameters of the pressure sensor 1 of the small wireless vacuum gauge 10 (To: sensor output value at atmospheric pressure, Tmax: sensor output value in vacuum state, P _1/2 : sensor output value In addition, various parameters of the core material (λsr: thermal conductivity of dry air, λga: thermal conductivity under atmospheric pressure, P _1/2 : under vacuum (1 Pa or less ) can be received by adding the thermal conductivity values and dividing by two. In this way, the value of the calibration result of the pressure sensor and the core material can be set in advance.

In the threshold input field in the display screen shown in FIG. 5, it is possible to receive the input of the manufacturing date of the vacuum insulation material, and the input of the thermal conductivity inside the vacuum insulation material and the service life as the threshold. The terminal 40 can display a graph or the like on the display screen as a long-term performance prediction result and determination, based on the prediction result of the thermal insulation performance change calculated by the server 30 . If the prediction result does not exceed the thermal conductivity and the number of years specified in advance as thresholds, the judgment is displayed as good (o), and in addition, the replacement time (for example, after the third year) can be displayed.

FIG. 6 is a flow chart showing the flow of processing for converting the output value obtained from the pressure sensor in the compact wireless vacuum gauge into a pressure value. The processing is executed by the pressure gradient calculation unit 311 of the server 30 . First, the measurement data measured by the pressure sensor 1 (see FIG. 2) acquired from the compact wireless vacuum gauge 10 and accumulated in the measurement data storage unit 381 of the server 30 is obtained (step S100). Next, the parameters of the core material are obtained (step S101). The parameters of the core material can be input by the user through the display screen shown in FIG. Finally, the core material parameters and measurement data are converted into pressure values (S102).

The conversion from the measured data to the pressure value is, for example, various parameters of the pressure sensor 1 input by the user via the display screen shown in FIG. 5 (To: sensor output value at atmospheric pressure, Tmax: By substituting the sensor output value, P _1/2 : the pressure when the sensor output value is halved) into the theoretical formula y = Tmax/(1+x/(P _1/2 ))-To, the conversion is can do. x in the theoretical calculation formula is the internal pressure (Pa), and y is the output value of the measurement data of the pressure sensor 1 of the small wireless vacuum gauge 10 . FIG. 7 shows the results plotted on a graph with the internal pressure (Pa) on the x-axis and the output value of the pressure sensor 1 (micro vacuum sensor output value) on the y-axis.

Various parameters of the core material (λsr: thermal conductivity of dry air, λga: thermal conductivity under atmospheric pressure, P _1/2 : under vacuum (1 Pa or less) can be converted by substituting into the theoretical formula y = λsr + λga/(1+(P _1/2 )/x) x in the theoretical formula is the internal pressure (Pa ), and y is the thermal conductivity (mW/mK) of the core material (glass wool) of the vacuum insulation material 20. With the x-axis as the internal pressure (Pa) and the y-axis as the thermal conductivity of the core material, the graph is shown in Figure 8. Figure 9 is a graph in which the graphs shown in Figures 7 and 8 are superimposed.

FIG. 10 is a flow chart showing the flow of processing for determining the heat insulating performance of the vacuum heat insulating material after a specified period has elapsed, based on the thermal conductivity converted from the pressure gradient value. In step S110, the pressure gradient calculation unit 311 of the server 30 calculates ΔPa (internal pressure−past (initial) internal pressure/number of days of measurement) from the data accumulated in the storage unit 38 (measurement data storage unit 381, internal pressure value storage unit 382). calculate. A formula for calculating ΔPa is based on the above-described formula (1).

In step S111, the performance determination unit 312 of the server 30 calculates long-term performance for a specified period based on the relational expression between internal pressure and thermal conductivity. Specifically, based on the above-described formulas (2) to (4), the replacement timing of the vacuum heat insulating material and the thermal conductivity inside the vacuum heat insulating material are calculated. In step S112, the performance determination unit 312 determines whether or not the calculated result exceeds the thermal conductivity (specified thermal conductivity) specified by the user as a threshold via the display screen shown in FIG. . If the specified thermal conductivity is exceeded (“Yes” in S112), the notification unit 313 notifies the user to replace the vacuum insulation material (S113), and if the specified thermal conductivity is not exceeded (“No” in S112), The notification unit 313 can display the predicted replacement time on the screen of the terminal 40 (output unit 47). Prediction of the time to replace the vacuum heat insulating material can be determined, for example, based on the correlation coefficient between the current value and the past value of the pressure gradient value (Formulas (3) and (4) described above).

A vacuum insulation material equipped with a micro vacuum sensor was allowed to stand in the environment shown in the table below, and the long-term performance (change in thermal conductivity over time) was measured and compared with the performance converted from the internal pressure.

Various parameters of the core material (λsr: Solid and radiant thermal conductivity of the core material when the atmospheric pressure Pa is 1 Pa or less, λga: Thermal conductivity under atmospheric pressure, P _1/2 : Under vacuum (1 Pa or less ) and divided by 2, the atmospheric pressure value at the time of thermal conductivity) is as shown in the table below.

The thermal conductivity λ _cop (also referred to as “calculated thermal conductivity”) calculated based on the above formula (2) is obtained, and the value (current value) of the calculated thermal conductivity λ _cop and the value obtained in the past A correlation coefficient with a value (past value) was calculated based on Equation (4) described above. The results are shown in the table below. On the 190th day, a hole was made in the vacuum insulation material with a needle hole, and the hole was closed with a curing tape to intentionally cause a decrease in performance.

FIG. 11 is a graph showing the relationship (pressure gradient) between the internal pressure of the vacuum heat insulating material and the period (days). Such a graph can be displayed on the display screen shown in FIG. 5 as the long-term performance prediction result. As can be seen from the graph shown in FIG. 11, the internal pressure basically increases at a constant rate over time. If the performance drops significantly, the correlation coefficient drops significantly as shown in the table above, so an alert can be issued under the following conditions. (1) Display an alert when the performance estimated from the past four pressure measurement results exceeds the performance (age and thermal conductivity) specified by the user. (2) If the correlation coefficient is less than 0.7 and it is estimated that there is a problem with product performance, an alert is displayed.

As for (1), a notification is displayed in the process of the product's performance naturally changing, saying that "the performance will be 〇mW/mK after 〇years." Alerts can be displayed. On the other hand, if the performance suddenly changes as in (2), it is assumed that there is some kind of problem with the product. It will be possible to provide from the prediction system.

With the above configuration, the thermal insulation performance change prediction system according to one embodiment of the present invention predicts changes in the thermal insulation performance of the vacuum insulation material after several years or later based on the calculated pressure gradient. In addition, based on predicted changes in insulation performance, alerts regarding the replacement timing and current insulation performance of vacuum insulation materials can be sent to those who monitor long-term changes in insulation performance of vacuum insulation materials (construction contractors). , manufacturers, etc.).

INDUSTRIAL APPLICABILITY The vacuum insulation material according to the present invention can be used for the outer walls of houses, plants, etc., in order to efficiently utilize thermal energy. In particular, it can be used for long-term operation and performance prediction of the vacuum insulation material by measuring the insulation performance after construction of the vacuum insulation material.

1 pressure sensor 2 operational amplifier 3 A/D converter 4 CPU/wireless transmission unit 5 temperature/humidity sensor/internal clock 6 charging unit 7 DC/DC converter 8 battery 10 small wireless vacuum gauge 20 vacuum insulation material 30 server 31 CPU
311 pressure gradient calculation unit 312 performance determination unit 313 notification unit 33 memory 34 bus 35 input/output interface 36 input unit 37 output unit 38 storage unit 381 measurement data storage unit 382 internal pressure value storage unit 39 communication unit 40 terminal 41 CPU
411 browser program 43 memory 44 bus 45 input/output interface 46 input unit 47 output unit 48 storage unit 49 communication unit N network

Claims (8)

A compact wireless vacuum provided inside the outer layer of a vacuum insulation material that includes a core material, a gas barrier film covering the core material, and an outer layer provided outside the gas barrier film, the inside of which is vacuum-sealed. a storage unit for storing measurement data obtained from a compact wireless vacuum gauge, which includes at least a pressure sensor and a transmission unit for transmitting measurement data measured by the pressure sensor;
An internal pressure value indicating the internal pressure of the vacuum insulation material at the time of measurement by the pressure sensor is obtained from the measurement data, and an internal pressure difference between the internal pressure value and a past internal pressure value representing the past internal pressure of the vacuum insulation material. and a pressure gradient calculation unit that obtains a pressure gradient value representing the amount of change in the internal pressure difference per unit time;
a performance determination unit that determines the thermal insulation performance of the vacuum insulation material after a specified period of time has elapsed based on the thermal conductivity converted from the pressure gradient value;
a notification unit that notifies according to the determination result of the performance determination unit;
The performance determination unit determines whether the thermal conductivity is equal to or higher than a predetermined thermal conductivity,
The thermal insulation performance change prediction system, wherein the notification unit issues a notification to prompt replacement of the vacuum insulation material when the performance determination unit determines that the thermal conductivity is equal to or higher than the specified thermal conductivity. 2. The thermal insulation performance change prediction system according to claim 1, wherein the pressure gradient value is calculated by the following formula (1).

However, ΔPa is the pressure gradient value, Pac is the internal pressure value of the vacuum insulation material at the time of measurement, _{Pa a is} the past internal pressure value measured earlier than _Pac , and Day is the number of days between the measurement of _Paa and the measurement of _Pac . 3. The thermal insulation performance change prediction system according to claim 2, wherein the thermal conductivity is calculated by the following formula (2).

where λ _cop is the thermal conductivity of the central part of the vacuum insulation, λ _sr is the solid and radiant thermal conductivity of the core material, λ _ga is the thermal conductivity of dry air, and P _1/2 is Add the thermal conductivity value of the core material under atmospheric pressure and the value of thermal conductivity under vacuum (1 Pa or less) and divide by 2. Atmospheric pressure value at the time of thermal conductivity, t is the replacement time and the value t representing the replacement timing is the value of the previously specified specified period . The thermal insulation performance according to any one of claims 1 to 3 , wherein the notification unit notifies the period or time until the thermal conductivity of the vacuum insulation material reaches the specified thermal conductivity. Change prediction system. The notification unit notifies the period or time until the specified thermal conductivity is reached when the performance determination unit determines that the thermal conductivity is less than the specified thermal conductivity. Item 5. The thermal insulation performance change prediction system according to item 4 . The performance determination unit further determines that a correlation coefficient between the current value of the thermal conductivity λ _cop and one or more past values obtained in the past by the performance determination unit is equal to or greater than a predetermined correlation coefficient. and determine whether or not
The notification unit is characterized in that, when the performance determination unit determines that the correlation coefficient is less than the specified correlation coefficient, the notification unit issues a notification prompting replacement of the vacuum insulation material or a warning notification of an abnormality. The thermal insulation performance change prediction system according to any one of claims 1 to 5 . 7. The thermal insulation performance change according to claim 6 , wherein the correlation coefficient is calculated by the following formula (4), where X is the current value of the thermal conductivity λ _cop and Y is the past value. prediction system.

A thermal insulation performance change prediction program that causes a computer to function as the thermal insulation performance change prediction system according to any one of claims 1 to 7 .

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