JP2019168137A - Heat storage material temperature detection device and heat storage device - Google Patents

Abstract

To provide a heat storage material temperature detection device that can detect melting of a latent heat storage material.SOLUTION: A heat storage material temperature detection device according to an embodiment is a heat storage material temperature detection device for detecting a melting state of a latent heat storage material housed in a container, and comprises a temperature sensor and determination means. The temperature sensor is arranged in a lower part of the container housing the latent heat storage material, and measures a temperature of the latent heat storage material. The determination means determines the melting state of the latent heat storage material on the basis of the temperature of the latent heat storage material measured by the temperature sensor.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a heat storage material temperature detection device and a heat storage device.

  2. Description of the Related Art A heat storage device that uses supercooling of a latent heat storage material capable of phase change is known. This heat storage device applies radiant heat to the latent heat storage material in a supercooled state, stores the heat, and when a heat release is requested, releases the supercooled state and changes the phase of the latent heat storage material from liquid to solid. The latent heat released along with it is used.

  It is called “nucleation” to release the supercooled state of the latent heat storage material in the liquid phase after being supercooled and to change the phase of the latent heat storage material from liquid to solid. When the nucleation operation is performed while the latent heat storage material is in the liquid phase, crystal nuclei are formed in the latent heat storage material that is supercooled and in the liquid phase, and crystallization starts from that point.

  In recent years, there has been a demand for a heat storage device from the viewpoint of efficient use of energy, and a highly reliable heat storage device has been demanded. Applications of the heat storage device include applications in which solar heat during the day is used as heating at night, heating assistance, and unsteady heat utilization.

  The subcooling latent heat storage material used in the heat storage device does not become a supercooled liquid unless the latent heat storage material is melted, and there is a problem that heat cannot be extracted when crystallization heat is generated from the residual crystal nuclei and extraction is desired.

  In order to solve these problems, a means for melting the latent heat storage material and confirming that it is in a molten state is necessary. Therefore, the melting of the latent heat storage material is generally detected by laser scattering and spectroscopic detection. However, these methods have various problems such as an increase in apparatus volume, an increase in mounting area, and a high cost.

JP 2007-285549 A JP 2007-333294 A

  The problem to be solved by the present invention is to provide a heat storage material temperature detection device and a heat storage device that can stably detect melting of the latent heat storage material.

  The heat storage material temperature detection device of the embodiment is a heat storage material temperature detection device that detects the melting state of the latent heat storage material housed in the container, and includes a temperature sensor and a determination unit. A temperature sensor is arrange | positioned at the low part of the container which accommodates a latent heat storage material, and measures the temperature of the said latent heat storage material. The determination means determines the melting state of the latent heat storage material based on the temperature measured by the temperature sensor of the latent heat storage material.

Schematic of a thermal storage apparatus provided with the thermal storage material temperature detection apparatus which concerns on 1st Embodiment. The schematic which inclined the heat storage apparatus provided with the heat storage material temperature detection apparatus which concerns on 1st Embodiment. The figure which has arrange | positioned one temperature sensor of the thermal storage material temperature detection apparatus which concerns on 1st Embodiment in the low part of the container. The figure which has arrange | positioned multiple temperature sensors of the thermal storage material temperature detection apparatus which concerns on 1st Embodiment in the low part of the container. The heat storage material temperature detection apparatus which concerns on 1st Embodiment incorporates the temperature sensor, and is the figure arrange | positioned in the low part of the container. The step figure which determines melting of the latent heat storage material of the determination means with which the thermal storage material temperature detection apparatus which concerns on 1st Embodiment is provided. The flowchart which determines the melting point of the latent heat storage material of the determination means with which the thermal storage material temperature detection apparatus which concerns on 1st Embodiment is provided. The figure which shows the melting point of the latent heat storage material of the determination means with which the thermal storage material temperature detection apparatus which concerns on 1st Embodiment is provided. Schematic which has arrange | positioned the thermal storage material temperature detection apparatus which concerns on 2nd Embodiment in the container. The conceptual diagram which shows the high part, the middle part, and the low part in 2nd Embodiment. The figure which shows the melting point in the high part of the latent heat storage material, the middle part, and the low part in the thermal storage material temperature detection apparatus which concerns on 2nd Embodiment. The figure which has arrange | positioned two or more temperature sensors of the thermal storage material temperature detection apparatus which concerns on 2nd Embodiment in the high part of the container, the middle part, and the low part. The figure which has arrange | positioned the temperature sensor of the thermal storage material temperature detection apparatus which concerns on 2nd Embodiment to the high part and the low part of a container one each, or to the middle part and the low part. The flowchart which determines the melting point of the latent heat storage material of the determination means with which the thermal storage material temperature detection apparatus which concerns on 2nd Embodiment is provided. The graph which showed the point which determined the latent heat storage material temperature change and melting point in Example 1. FIG. The graph which showed the point which determined the latent heat storage material temperature change and melting point in Example 2. FIG. The graph which showed the point which determined the latent heat storage material temperature change and melting point in Example 3. FIG. The graph which showed the point which determined the latent heat storage material temperature change and melting point in Example 4. FIG. The graph which showed the point which determined the latent heat storage material temperature change and melting point in Example 5. FIG. The graph which showed the point which determined the latent heat storage material temperature change and melting point in the comparative example 1. FIG. The graph which showed the point which determined the latent heat storage material temperature change and melting point in the comparative example 2. FIG. The graph which showed the point which determined the latent heat storage material temperature change and melting point in the comparative example 3. FIG.

  Hereinafter, embodiments will be described with reference to the drawings. In addition, the same code | symbol shall be attached | subjected to a common structure through embodiment, and the overlapping description is abbreviate | omitted.

(First embodiment)
FIG. 1 is a schematic diagram of a heat storage device 20 including a heat storage material temperature detection device 10 according to the first embodiment. The heat storage device 20 includes a heat storage material temperature detection device 10, a heat storage unit 21, and a control unit 22. The heat storage unit 21 is configured integrally with a container 211 for storing a latent heat storage material (not shown), a heat collecting plate 212, and a heat insulating material 213, and includes a nucleation means 214 therein. The heat storage material temperature detection apparatus 10 according to the present embodiment is based on the temperature sensor 11 that is disposed in the lower part of the container 211 that stores the latent heat storage material and measures the temperature of the latent heat storage material, and the temperature measured by the temperature sensor 11. Determination means 12 for determining the melting state of the latent heat storage material. The container 211 has a heat storage surface on which the heat collecting plate 212 and the heat insulating material 213 are provided, and another surface on which the heat insulating material 213 is provided. The temperature sensor 11 is disposed outside the container 211 and at a lower portion of the container 211 and between a surface other than the heat storage surface and the heat insulating material 213. The temperature of the latent heat storage material is transmitted to the temperature sensor 11 through the container 211.

  The control unit 22 includes a power supply unit and a control circuit (not shown). The control unit 22 forms a unit, for example, and is provided, for example, on the outside (outer surface) of the heat storage unit 21. The control unit 22 may be provided separately from the heat storage unit 21. Further, it may be connected to or incorporated in a system for controlling a solar power generator, an air conditioner or the like as shown in an application example described later. The power supply unit is connected to the nucleation means 214. The control unit 22 and the nucleation means 214 are not shown except for FIG.

  The heat storage material temperature detection device 10 can be installed both indoors and outdoors.

  In addition, in this embodiment, a low part shows a low part (low part) in the gravity direction of the container 211 in the state by which the thermal storage apparatus is arrange | positioned. Therefore, when the arrangement of the container 211 is changed, the lower part may be changed by changing the direction of gravity in accordance with the change in the arrangement.

  Here, the lower part of the container 211 will be described in detail. The container 211 can be variously arranged depending on the position of the heat source. Moreover, the container 211 can also take various shapes according to a use. Here, the case where the container 211 is a substantially rectangular parallelepiped will be described as an example.

  When this container 211 is placed on the ground with the heat collecting plate 212 facing the heat source, the surface close to the ground is the bottom surface, the surface facing the bottom surface is the top surface, and the other surfaces are the side surfaces.

  FIG. 1 is a schematic diagram of a heat storage device 20 including the heat storage material temperature detection device 10 according to the first embodiment, and is also a diagram in a state where the bottom surface of the heat storage unit 21 is parallel to the ground, that is, in a flat state. is there. Thus, in FIG. 1, it arrange | positions so that the upper surface of the container 211 and a heat source may oppose. Therefore, the lower part when the container 211 is placed flat, that is, parallel to the ground is the bottom part. For this reason, in the present embodiment, the temperature sensor 11 is disposed on the bottom surface.

  Next, FIG. 2 is the schematic which inclined the heat storage apparatus 20 provided with the heat storage material temperature detection apparatus 10 which concerns on 1st Embodiment. Inclination means that the angle (inclination angle) formed by the heat storage unit 21 and the ground is greater than 0 degrees and equal to or less than 90 degrees. Inclining so that the inclination angle is 90 degrees refers to, for example, a case where it is arranged so as to be attached to a window. The low portion when the container 211 is disposed at an inclination as shown in FIG. 2 indicates a portion close to the ground on the bottom surface, such as a portion surrounded by a dotted line in FIG. And the temperature sensor 11 is arrange | positioned in this part.

  In addition, the lower portion in the case where the container 211 is circular, spherical, elliptical, or the like refers to the side opposite to the side close to the heat source and the side closer to the ground on the opposite side.

  Although the low part of the container 211 may refer to a surface or a part, it indicates a part close to the ground on the bottom surface or the bottom surface described above. 3, 4, 5, 9, 10 </ b> C, 12, and 13 are views when the container 211 is viewed from the bottom surface, and the lower side of the figure is a low portion. In FIG. 3 and subsequent figures, the heat collecting plate 212 and the heat insulating material 213 are not shown because the drawing becomes complicated. Note that the definition of the low part is not related to the thickness, area, and volume of the container.

  The temperature of the latent heat storage material is detected by the temperature sensor 11 via the container 211, and the detected temperature is transmitted to the determination unit 12 that determines melting of the latent heat storage material. The temperature sensor 11 and the determination means 12 are connected and communicated by at least one of wired and wireless.

  From the viewpoint of convection and gravity, the latent heat storage material tends to become high and melt easily when the temperature of the high portion of the container 211 is collected. On the other hand, the latent heat storage material temperature in the lower part of the container 211 is kept low, and the crystallized product accumulates in the lower part as a semi-molten crystallized product due to gravity, so that it becomes more difficult to melt. Therefore, the lower part of the container 211 is in a range where the latent heat storage material hardly reaches the melting temperature.

  Furthermore, the latent heat storage material may change greatly from latent heat behavior (crystallized product is melted) with almost no temperature change near the melting point to sensible heat behavior (crystallized product to melt) where the temperature suddenly rises. . If that time is taken as the melting point, it is possible to determine that the latent heat storage material has been melted through the container 211 by capturing this melting point. In the latent heat storage material, since the temperature behavior occurs most slowly in the lower part of the container 211, the temperature sensor 11 is installed in the lower part of the container 211, and the determination unit 12 is provided for determining when the temperature is melted. The melting of the latent heat storage material in the entire interior of the container 211 can be determined.

  Therefore, the temperature sensor 11 disposed in the lower portion of the container 211 intermittently measures the temperature of the latent heat storage material, and based on the temperature information, the determination means 12 melts the latent heat storage material with respect to the time of the latent heat storage material. By calculating the temperature change (that is, the slope), the melting point can be determined with high accuracy. The determination of the melting point will be described later in detail.

  FIG. 3 is a diagram in which one temperature sensor 11 of the heat storage material temperature detection device 10 according to the first embodiment is arranged in the lower part of the container 211. FIG. 4 is a diagram in which a plurality of temperature sensors 11 of the heat storage material temperature detection device 10 according to the first embodiment are arranged in the lower part of the container 211. As shown in FIGS. 3 and 4, when the temperature sensor 11 is arranged in the lower part of the container 211, one or more temperature sensors 11 may be arranged. By arranging a plurality, it is more preferable because a temperature change in the lower part can be detected more accurately.

  Here, the heat storage material temperature detection device 10 will be described in detail. The heat storage material temperature detection device 10 includes the temperature sensor 11 and the determination unit 12 that determines melting of the latent heat storage material as described above. Therefore, the heat storage material temperature detection device 10 may be an independent device, or a latent heat storage device that includes a temperature sensor 11 and a determination unit 12 in a user device such as a user's personal computer, a smartphone, or a mobile terminal. The material temperature detection device 10 may be used.

  When the heat storage material temperature detection apparatus 10 exists independently, the heat storage material temperature detection apparatus 10 can also be provided with a power supply. This power supply can be operated directly by the user, or remotely operated by a remote controller or the like. The operation may be started in conjunction with the start of heat collection.

  The heat storage material temperature detection device 10 and the temperature sensor 11 may be provided on a one-to-one basis as shown in FIGS. 3 and 4A, or a plurality of heat storage material temperature detection devices 10 may be provided for one heat storage material temperature detection device 10 as shown in FIG. 4B. A temperature sensor 11 can also be provided. When the heat storage material temperature detection device 10 and the temperature sensor 11 are on a one-to-one basis, when the temperature sensor 11 is attached to the plurality of containers 211, it is possible to reduce the risk of failure. Moreover, when attaching the several temperature sensor 11 with respect to the one heat storage material temperature detection apparatus 10, the information of the several temperature sensor 11 can also be managed by the one heat storage material temperature detection apparatus 10. FIG.

  The determination means 12 provided in the heat storage material temperature detection device 10 will be described later.

  Here, each member of the heat storage material temperature detection device 10 will be described in detail.

(Temperature sensor)
A thermocouple or the like can be used for the temperature sensor 11, but the shape, length, thickness, and the like are not particularly limited to match each container shape. For example, a temperature sensor equivalent to a temperature sensor built in a thermocouple, a smartphone, or a mobile phone, or a temperature sensor built in a battery pack can be used.

  FIG. 5 is a diagram in which the heat storage material temperature detection device 10 according to the first embodiment includes the temperature sensor 11 and is disposed in the lower part of the container 211. Thus, the heat storage material temperature detection device 10 may incorporate the temperature sensor 11. Also in this case, the heat storage material temperature detection device 10 can include a plurality of temperature sensors 11.

  Next, the determination unit 12 will be described.

(Judgment means)
The determination means 12 is programmed and incorporated in the device. The device incorporating the determination unit 12 may incorporate the determination unit 12 from the beginning, or may be downloaded via the Internet or the like. Moreover, you may provide the determination means 12 in user's apparatuses, such as a computer, a smart phone, and a portable terminal. Also in this case, the programmed determination means 12 can be downloaded through the Internet or the like. The determination means 12 and the temperature sensor 11 are connected wirelessly or by wire.

  FIG. 6 is a step diagram for determining the melting of the latent heat storage material of the determination means 12 included in the heat storage material temperature detection device 10 according to the first embodiment. Thus, the determination means 12 can determine the melting of the latent heat storage material by the steps shown in FIG. 6 based on the temperature information obtained from the temperature sensor 11 disposed in the lower part of the container 211.

  Obtain temperature information of the latent heat storage material measured by the temperature sensor 11 at regular intervals (step 1), then calculate the slope of the temperature change using the temperature obtained in step 1 (step 2), then step The melting of the latent heat storage material is determined based on the point at which the slope due to the temperature change obtained in 2 has changed for the second time (step 3).

  FIG. 7 is a flowchart for determining the melting point 30 of the latent heat storage material of the determination means 12 included in the heat storage material temperature detection device 10 according to the first embodiment, and FIG. 8 is the heat storage material temperature detection according to the first embodiment. It is a figure which shows the melting point of the latent heat storage material of the determination means 12 with which the apparatus 10 is provided. The steps will be described in detail with reference to FIGS. 7 and 8. When the latent heat storage material is exposed to heat, the temperature rises until the latent heat storage material itself is heated to a certain temperature (first slope). Next, when the latent heat storage material reaches a certain temperature, it takes a latent heat behavior with almost no temperature change, so the gradient of the temperature change of the latent heat storage material becomes a gentler gradient than the first gradient (second gradient). . Finally, when the latent heat storage material changes from the latent heat behavior to the sensible heat behavior, the temperature of the latent heat storage material increases, so that the inclination becomes larger than the second inclination (third inclination). The point indicating the melting of the latent heat storage material in Step 3 (melting point 30) is shown in FIG.

  That is, the change in the slope due to the temperature change in Step 3 is the first change (first change) that changes from the first slope to the second slope, and the change from the second slope to the third slope. This is the second change (second change). The determination means 12 determines this second change, thereby determining the melting of the latent heat storage material. The measurement of the change in the temperature of the latent heat storage material with time is continuous measurement or measurement at every elapse of a fixed time. The measurement interval in the case of measuring every certain time elapses is appropriately set, for example, by measuring every minute by using a latent heat storage material or a heat source. The magnitudes of the first and third inclinations do not matter.

  Further, by connecting the determination means 12 to the nucleation means 214, the determination means 12 can be automatically provided with a program such as nucleation and state maintenance after the melting determination.

  The heat storage material temperature detection device 10 may be directly connected to a device such as a personal computer, a smartphone, or a mobile terminal by radio or wire. By connecting in such a manner, the data obtained by the heat storage material temperature detection device 10 (for example, the temperature change of the latent heat storage material and the melting point) is stored in the computer, smartphone, portable terminal, etc. of the user at the connection destination, It can also be used by adding analysis, feedback, and learning functions, and raising the melting judgment system.

(Heat storage part)
The heat storage unit 21 includes a container 211 for storing a latent heat storage material, a heat collecting plate 212, and a heat insulating material 213. The container 211 may take various shapes such as rectangular (horizontal, vertical), cubic (dice, thin, thick), circle, ellipse, sphere, heart, and so on. Examples include bags, laminate packs, metal containers, and hot water bottles.

  When the weight of the latent heat storage material is large, the heat generation amount increases, but the heat of fusion increases, so the melting time tends to be longer. In general, depending on whether the heat source is placed on one surface of the container 211 or arranged in a multifaceted manner, the latent heat storage material is more easily melted when the wall portion of the container 211 is thinner and the area is smaller.

  On the other hand, if the wall portion of the container 211 is thick, it is difficult to melt. This is because the heat conductivity of the latent heat storage material itself is low, so that the efficiency of heat conduction through the container 211 decreases as the wall portion of the container 211 increases in thickness, and the latent heat storage material becomes difficult to melt. In addition, the larger the area, the more difficult the heat is transferred to the center of the container 211, so the latent heat storage material is less likely to melt.

  The container 211 contains a latent heat storage material and a nucleation means 214 inside. As the container 211, a resin container, a metal container, a metal / resin composite container, and a bag made of a film of these materials (for example, an aluminum laminate material) can be used. It is preferable to use a member that can follow the volume change accompanying the solidification / melting of the latent heat storage material for the container 211.

  The nucleation means 214 functions to solidify (crystallize) the latent heat storage material in a supercooled state, with the latent heat storage material in contact with a part thereof. By providing the nucleation means 214, for example, the switch can be arbitrarily switched on after sunset to promote nucleation, and the radiant heat from this device can warm up. Specific nucleation methods include inserting two electrodes and applying a voltage between the electrodes, applying ultrasonic waves, changing the wettability (contact angle), a plate spring and an actuator with irregularities. A method of moving the leaf spring with an actuator, a method of applying a voltage to the thermoelectric element to quench the electrode extremely, a method of introducing crystal nuclei from the crystal nucleus storage container 211, and generating nuclei can be used.

  In order to collect heat efficiently, it is preferable to arrange the heat storage unit 21 so that the surface on which the heat collecting plate 212 is arranged has the best heat absorption. The heat storage unit 21 may be provided with support legs so that the arrangement can be changed as appropriate. For example, when sunlight is used as a heat source, from the viewpoint of solar heat collection efficiency, the heat storage unit 21 is standing (at a right angle) or inclined (at a right angle with respect to the maximum solar altitude) with respect to the solar altitude. Is preferred. That is, it is preferable that the inclination angle is greater than 0 degree and 90 degrees or less. For the heat collecting plate 212, for example, a metal such as aluminum or copper can be used.

  As the heat insulating material 213, a material having low heat conductivity and high heat resistance can be used. For example, glass wool, bead method polystyrene / extruded polystyrene foam (styrene foam) can be used.

  The heat source used for collecting heat is not limited as long as it generates radiant heat. For example, the sunlight mentioned above, a ceramic heater, etc. are mentioned. Use of sunlight is preferable because it does not cost necessary to generate heat.

  As the latent heat storage material, it is preferable to use a latent heat storage material having a melting point in the range of room temperature (20 ° C.) to 100 ° C. and having supercooling. A latent heat storage material having supercooling is a substance that does not solidify even at a temperature below the melting point and exists in a liquid and metastable state. For example, sodium acetate such as sodium acetate trihydrate or sulfuric acid such as sodium sulfate hydrate. Soda can be used. When the heat storage temperature is high, it is desirable to use sodium acetate trihydrate as the latent heat storage material. The general physical properties of sodium acetate trihydrate are a melting point of 58 ° C. and a latent heat of 264 kJ / kg.

  As shown in FIG. 3, the heat storage material temperature detection device 10 can also be provided with a display unit 23 that can display the temperature status of the latent heat storage material and the user to notify the melting of the latent heat storage material. .

(Display section)
The display unit 23 is electrically connected to the heat storage material temperature detection device 10. For this reason, the heat storage material temperature detection device 10 can be connected and communicated wirelessly or by wire to be independent, or may be directly provided in the heat storage material temperature detection device 10. A display, an LED lamp, or the like can be used for the display unit 23, but the display method is not particularly limited. It is more preferable if temperature display (color and numerical value display) can be performed. That the display unit 23 exists independently may use the above-described display or LED lamp, or the heat storage material temperature detection device 10 transmits a signal such as a temperature change of the latent heat storage material, and other devices, for example, use It is good also as a display part 23 by making a person's personal computer, a smart phone, and a portable terminal receive. By providing the display unit 23, it is confirmed whether the temperature measurement supercooled state is maintained continuously or discontinuously. That is, it can be confirmed whether or not the latent heat storage material can be nucleated. Furthermore, it is more preferable if a display and a signal capable of nucleation can be output.

  Here, the operation of the latent heat material temperature detection device according to the present embodiment will be described.

1. The temperature sensor 11 is disposed in the lower part of the container 211 containing the latent heat storage material. At this time, it arrange | positions so that the heat collecting plate 212 can absorb heat efficiently with respect to a heat source.

2. Turn on the heat storage material temperature detection processing device.

3. Prior to use, the latent heat storage material in the container 211 is heated in advance to a temperature equal to or higher than the melting point (heat (temperature) input). As a result, the latent heat storage material is dissolved to be in a liquid phase. Moreover, since the latent heat storage material is a latent heat storage material that can be supercooled, even if the latent heat storage material becomes below the melting point after completion of heat input, the liquid phase state is maintained without solidifying (becomes a supercooled state). ). In this state, the latent heat storage material continues to store latent heat.

4). The temperature sensor 11 is activated at the time of heat collection, that is, when radiant heat is applied to the latent heat storage material container 211, and records temperature change with time (vs. time) of the lower part of the container 211.

5. The determination means 12 receives this temperature change with time, and from the latent heat behavior near the melting point of the latent heat storage material (the crystallized product is melted: almost no temperature change), the sensible heat behavior (melted from the crystallized product: the temperature suddenly increases). Is detected), the melting of the latent heat storage material is determined.

6). When the determination unit 12 determines melting, the display unit 23 notifies the user of melting of the latent heat storage material. Furthermore, the determination means 12 may be provided with a program that continues to maintain melting to maintain melting.

  In addition, 2. Turning on the heat storage material temperature detection processing apparatus is appropriately omitted when it is not necessary to turn on the power, such as when the user's device is provided with the temperature sensor 11 and the determination means 12.

  The latent heat material temperature detection device according to the present embodiment can measure the temperature change of the latent heat storage material with time by arranging the temperature sensor 11 in the lower part of the container 211 containing the latent heat storage material. Furthermore, by including a determination unit 12 that determines melting of the latent heat storage material based on the temperature of the latent heat storage material measured by the temperature sensor 11, the latent heat storage material of the latent heat storage material inside the container 211 from the outside of the container 211. Can be determined. For this reason, crystallization heat can be prevented from the residual crystal nuclei that exist because the latent heat storage material is incompletely melted, so that heat can be extracted from the latent heat storage material when necessary.

(Second Embodiment)
A description common to the first embodiment is omitted.

  FIG. 9 is a schematic view in which the heat storage material temperature detection device 10 according to the second embodiment is arranged in a container 211. In the heat storage material temperature detection device 10 according to the second embodiment, the temperature sensor 11 can be arranged in the high portion, the middle portion, and the low portion outside the container 211. The low part is as described in the first embodiment. FIG. 10 is a conceptual diagram showing a high part, a middle part, and a low part in the second embodiment. Here, the high portion and the middle portion will be described with reference to FIGS. 10A, 10B, and 10C.

  As shown in FIG. 10A, the high portion when the container 211 is laid flat is the upper surface or the upper surface side of the side surface, that is, the portion far from the ground. The middle part in this case is between the high part and the low part.

  Next, as shown in FIG. 10B, the high portion when the container 211 is disposed at an inclination is the one far from the ground at the bottom. That is, the high portion is the opposite side of the low portion on the bottom surface. Also in this case, the middle part is between the high part and the low part. When tilted in this way, the same applies to the high portion and the middle portion when the container 211 is viewed from the bottom as shown in FIG. 10C.

  In addition, when the container 211 is circular, spherical, elliptical, or the like, the high portion is the side opposite to the side close to the heat source and the side farther from the ground on the opposite side. In addition, whatever the shape of the container 211, the middle part is between the high part and the low part.

  In order to determine the melting of the latent heat storage material, the melting state can be confirmed in stages by arranging the high part, the middle part, and the temperature sensor 11 in addition to the low part of the container 211 containing the latent heat storage material. . As described above, the temperature of the latent heat storage material decreases as it goes to the lower portion of the container 211 due to convection or gravity. Therefore, as shown in FIG. 9, when the temperature change of the latent heat storage material when the temperature sensor 11 is arranged in the high part, the middle part, and the low part of the container 211 is shown, the temperature sensor 11 detects the temperature of the container 211 at a certain time. The temperature of each part becomes high part> middle part> low part. Therefore, as shown in FIG. 11, in the heat storage material temperature detection device 10 according to the second embodiment, the melting point 30 in the high, middle, and low parts of the latent heat storage material is shown. That is, the change in sensible heat behavior from latent heat also occurs in the order of the high part, the middle part, and the low part.

  By arranging in this way, it is possible to improve the accuracy of determination of melting of the latent heat storage material and the accuracy of stepwise confirmation of the melting state.

  FIG. 12 is a diagram in which a plurality of temperature sensors 11 of the heat storage material temperature detection device 10 according to the second embodiment are arranged in the high, middle, and low parts of the container. In this way, a plurality of temperature sensors 11 may be arranged, or one temperature sensor 11 may be arranged in each of the high part, the middle part, and the low part as shown in FIG. It is preferable to arrange a plurality of temperature sensors 11 as shown in FIG. 12 because the accuracy can be improved and the risk of failure of the temperature sensors 11 can be reduced. In FIG. 12, since the figure becomes complicated, a line connecting the determination unit 12 and the temperature sensor 11 is partially omitted.

  Moreover, FIG. 13 is the figure which has arrange | positioned the temperature sensor 11 of the thermal storage material temperature detection apparatus 10 which concerns on 2nd Embodiment one each at the high part of a container, the low part, or one part in the middle part and the low part. As shown in FIG. 13A and FIG. 13B, the temperature sensor 11 may be arranged only in the high part and the low part, or only in the middle part and the low part. In these cases as well, the behavior of the temperature change of the latent heat storage material is as described above, so that the location of the latent heat material temperature detection device and the container 211 can be changed as appropriate in addition to the low part according to the installation location of the container 211. .

  The determination means 12 determines the melting of the high, middle, and low latent heat storage materials in the same manner as described in the first embodiment. The flowchart which determines the melting point 30 of the latent heat storage material of the determination means 12 with which the thermal storage material temperature detection apparatus 10 which concerns on 2nd Embodiment is provided in FIG. 14 is shown.

  Here, operation | movement of the thermal storage material temperature detection apparatus 10 which concerns on this embodiment is demonstrated.

  The operations from 1 to 3 are the same as those in the first embodiment, and will be described from 4.

4). The heat storage material temperature detection device 10 is activated from the time of heat collection, that is, when radiant heat is applied to the container 211, and records the temperature change with time (vs. time) of the high, middle, and low parts of the container 211.

5. The determination means 12 receives the temperature aging of the high part, the middle part, and the low part, and captures the time (second change) at which each part changes from the latent heat behavior near the melting point of the latent heat storage material to the sensible heat behavior. The melting of the latent heat storage material at that portion is determined.

6). If the determination means 12 determines melting of the low part, the display unit 23 notifies the user of melting of the latent heat storage material. Furthermore, the determination means 12 may be provided with a program that continues to maintain melting to maintain melting.

  Here, the case where the temperature detectors are arranged in all of the high part, the middle part, and the low part is shown, but the same operation is performed in the case of only other high part and low part, only the middle part and low part, and the like.

  The heat storage material temperature detection device 10 according to the present embodiment adds the temperature sensor 11 to the lower part of the container 211 and arranges the temperature sensor 11 in at least one of the high part and the middle part, thereby changing the temperature change of the latent heat storage material over time. Can be measured. Furthermore, by providing the determination means 12 that can determine the melting of the latent heat storage material from the temperature change, the melting of the latent heat storage material inside the container 211 can be determined from the outside of the container 211. For this reason, crystallization heat generation can be prevented from the residual crystal nuclei that exist because of incomplete melting, so that heat can be taken out from the latent heat storage material when necessary. The accuracy of the stepwise confirmation can be improved.

(Application examples)
In the application example, an apparatus including the heat storage material temperature detection device 10 according to the first or second embodiment will be described.

<Solar cell>
In order to reduce the solar cell temperature during the day, a solar cell having a heat storage device including a container of a heat storage material arranged so as to be in thermal contact with the back surface side of the solar cell has been proposed. In a solar battery cell equipped with this heat storage device, the heat storage material may be completely melted during the day to reach a temperature higher than the melting point. Therefore, it is possible to determine the melting of the heat storage material by providing the temperature sensor 11 provided in the heat storage material temperature detection device 10 according to the first or second embodiment in the lower part of the container, and long-term heat storage, supercooling The liquid retention time can be sufficiently maintained. Thereby, since the solar cell temperature during the day can be lowered, the temperature of the solar cell can be kept at a high temperature and the power generation amount can be prevented from being lowered.

<Air conditioner>
An air conditioner including a heat storage device is used in combination with a heat exchange object. This heat storage device absorbs and stores the heat generated by the heat exchange object, and releases heat to the heat exchange object when the temperature of the heat exchange object decreases, so that heat can be absorbed and released stably. There wasn't. Then, in the air conditioner provided with the heat storage device, the heat storage material temperature detection device 10 according to the first or second embodiment is provided in the lower part of the container of the heat storage material provided in the heat storage device, so that heat is generated when necessary. It can be taken out from the latent heat storage material. Therefore, the air conditioner can always stably absorb and store the heat generated by the heat exchange object, and can release the heat to the heat exchange object when the temperature of the heat exchange object decreases. Efficiency can be improved.

<Image forming apparatus>
In the conventional image forming apparatus, it is necessary to quickly heat an object to be printed in the fixing operation. However, temperature unevenness may occur in the heating roller. Also, in order to equalize the temperature of the printing object, the heat of the printing object is absorbed by a roller filled with a heat storage material. The fixing unit cannot be cooled unless the output paper enters the fixing unit again by double-sided printing. Since the image forming apparatus having such a structure includes the heat storage material temperature detection device 10 according to the first or second embodiment, heat can be taken out from the latent heat material when necessary, thereby preventing temperature unevenness, and Since the cooling can be performed in a timely manner, an image forming apparatus with reduced power consumption can be obtained.

<Cooling system for transmission system for TV broadcasting>
Conventional cooling systems for television broadcasting transmission systems use circulating cooling water to cool, but the cooling water temperature may decrease due to environmental factors, which may affect the television broadcasting transmission system. It was. Although measures such as providing a temperature control valve for preventing the water temperature from lowering have been taken, the measures have increased the size and cost of the equipment. For this reason, in order to prevent the water temperature fall of cooling water, it is proposed to provide a heat storage device, and it is required that heat can be taken out from the latent heat storage material provided in the heat storage device when necessary. Therefore, with respect to the transmission system for television broadcasting provided with the heat storage device, the heat storage material temperature detection device 10 according to the first or second embodiment is provided to extract heat from the latent heat storage material when necessary. Can do. Therefore, it is possible to provide a transmission system that is space-saving and inexpensive and that can prevent a decrease in water temperature when the transmitter is activated.

<Battery module>
A secondary battery having a heat storage device including a container containing a latent heat storage material can keep the secondary battery warm in winter and cold regions. However, if measures are taken to insulate the latent heat storage material from the surrounding environment as a countermeasure for winter and cold regions, the possibility that the battery temperature will rise excessively in a high temperature environment such as summer is increased. Therefore, by providing the secondary battery having the heat storage device including the container containing the latent heat storage material with the heat storage material temperature detection device 10 according to the first or second embodiment, heat can be extracted from the latent heat material when necessary. In addition, it is possible to provide a battery module that can improve startability in a low temperature environment and can suppress a decrease in reliability due to excessive rise in battery temperature in a high temperature environment.

  About the apparatus demonstrated above, the point which was inadequate only by having provided the conventional latent-heat storage material is operated more efficiently by providing the thermal storage material temperature detection apparatus 10 which concerns on 1st or 2nd embodiment. I understand that.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited to a following example.

(Example)
Example 1
The heat storage device was placed upright at an inclination angle of 90 degrees. One temperature sensor was placed in the lower part of the container of the heat storage unit, and the heat storage material temperature detection processing device was turned on. The latent heat storage material in the container was previously heated to a temperature equal to or higher than the melting point. The temperature sensor was activated from the time of heat collection, and the temperature aging (vs. time) of the lower part of the container was recorded. The determination means received the temperature change with time of the latent heat storage material, and the melting of the latent heat storage material was determined. When the determination means determines melting, the display unit notifies the user of melting of the latent heat storage material.

  The temperature of the latent heat storage material was measured every second. Determination of melting of the latent heat storage material was performed by the determination means determining the second change in which the latent heat storage material changes from the latent heat behavior to the sensible heat behavior. FIG. 15 is a graph showing points at which the heat storage material temperature change and melting point in Example 1 were determined. The measurement conditions and results of Examples 1 to 5 and Comparative Examples 1 to 3 are summarized in Table 1.

  Judgment whether the latent heat storage material was not naturally crystallized was performed as follows.

<Natural crystallization judgment>
After the judgment means judged melting, it was confirmed whether the supercooled state (liquid phase state) was maintained at room temperature (15, 20, 25 ° C.) (1 day), that is, it was not spontaneously crystallized. (N = 2: Two heat storage material-containing containers subjected to melting determination under the same conditions).

  If the liquid in the container containing the latent heat storage material is not spontaneously nucleated and crystallized, and there are no residual crystal nuclei having a size larger than the critical diameter, it can be determined as melting. The case where the supercooled state (liquid phase state) was maintained was evaluated as ◯, and the case where it was not maintained was evaluated as ×.

  Similarly, Examples 2 to 6 and Comparative Examples 1 to 3 to be described later were judged as to whether they were naturally crystallized.

(Example 2)
The measurement was conducted in the same manner as in Example 1 except that the heat storage device was inclined and placed so that the heat collecting plate was 90 degrees with respect to the highest solar altitude (azimuth angle of about 180 degrees). FIG. 16 is a graph showing the points at which the temperature change and melting point of the latent heat storage material in Example 2 were determined.

Example 3
Measurement was performed under the same conditions as in Example 1 except that three temperature sensors were arranged in the lower part. FIG. 17 is a graph showing points at which the temperature change and melting point of the latent heat storage material in Example 3 were determined.

Example 4
The measurement was performed in the same manner as in Example 1 except that the temperature sensors were arranged one by one in the middle and the lower part of the container. FIG. 18 is a graph showing points at which the latent heat storage material temperature change and melting point in Example 4 were determined.

(Example 5)
Measurement was performed in the same manner as in Example 1 except that the temperature sensors were arranged in the high, middle, and low parts. FIG. 19 is a graph showing points at which the latent heat storage material temperature change and melting point in Example 5 were determined.

(Comparative Example 1)
The measurement was performed in the same manner as in Example 1 except that a temperature sensor was arranged at the upper part of the container containing the latent heat storage material. FIG. 20 is a graph showing points at which the temperature change and melting point of the latent heat storage material in Comparative Example 1 were determined.

(Comparative Example 2)
Measurement was performed in the same manner as in Example 1 except that a temperature sensor was arranged in the middle of the container containing the latent heat storage material. FIG. 21 is a graph showing the points at which the latent heat storage material temperature change and melting point in Comparative Example 2 were determined.

(Comparative Example 3)
The measurement was performed in the same manner as in Example 1 except that temperature sensors were arranged at the high and middle portions of the container containing the latent heat storage material. FIG. 22 is a graph showing points at which the temperature change and melting point of the latent heat storage material in Comparative Example 3 were determined.

  From Table 1, the melting could be confirmed in Examples 1 to 6. On the other hand, in Comparative Example 1, there were residual crystals, which were in a semi-solid phase (semi-liquid phase). That is, since the latent heat storage material was not in a supercooled state (liquid phase state), the latent heat storage material was not melted. In Comparative Examples 2 and 3, the supercooled state (liquid phase state) was not maintained after standing at room temperature for 1 day, and crystallization was generated. This is because there was crystal nucleus residue in the latent heat storage material, and it can be seen that the latent heat storage material was not melted.

  Based on the above, the temperature sensor that is disposed in the lower part of the container that stores the latent heat storage material and measures the temperature of the latent heat storage material, and the determination unit that determines the melting state of the latent heat storage material using the temperature are provided. It has been shown that the temperature detection device according to the first or second embodiment is a device for determining melting of an excellent latent heat storage material.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Thermal storage material temperature detection apparatus, 11 ... Temperature sensor, 12 ... Determination means, 20 ... Thermal storage apparatus, 21 ... Thermal storage part, 22 ... Control part, 211 ... Container 212 ... Heat collecting plate, 213 ... Heat insulating material, 214 ... Nucleation means, 23 ... Display part, 30 ... Melting point.

Claims (6)

A heat storage material temperature detection device for detecting a melting state of a latent heat storage material stored in a container,
A temperature sensor disposed at a lower portion of the container and measuring a temperature of the latent heat storage material;
Determination means for determining the melting state of the latent heat storage material based on the temperature measured by the temperature sensor;
A heat storage material temperature detection device.   The determination unit determines that the latent heat storage material has melted when a gradient of a temperature change when measuring a temperature change with the temperature sensor changes from substantially zero to a positive gradient. The heat storage material temperature detection apparatus according to 1.   The heat storage material temperature detection device according to claim 1 or 2, wherein another temperature sensor is disposed in at least one of a high portion and a middle portion of the container.   The heat storage material temperature detection apparatus according to any one of claims 1 to 3, further comprising a display unit that displays a state of the latent heat storage material. The heat storage material temperature detection device according to any one of claims 1 to 4,
A heat storage unit comprising a container for storing the latent heat storage material and a nucleation means for releasing the supercooled state of the latent heat storage material;
A heat storage device comprising:   The heat storage device according to claim 5, further comprising a control unit that controls the nucleation unit.

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