JP2015118012A - Specific heat-measuring device and specific heat-measuring method of test body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To calculate an apparent specific heat and a heat accumulation amount of test bodies of various types during temperature rise and during temperature decrease.SOLUTION: A specific heat-measuring device 20 includes: heating plates 22 which sandwich a test body 21 to increase and decrease a temperature of the test body; and heat flow meters 23 adhered between the test body 21 and the heating plates 22. The test body 21 has a thermocouple 26 adhered between two pieces of a test body piece 21a. These are stored inside a constant temperature and humidity room 25. The heating plate 22 is connected to a constant temperature water tank 28 via piping 27. A circulation liquid is heated or cooled inside the constant temperature water tank 28 and circulated to the heating plate 22. An atmospheric temperature of the constant temperature and humidity room 25 is controlled to be the same as the temperature of the circulation liquid inside the constant temperature tank 28. An apparent specific heat of the test body 21 is calculated based on the temperature of the test body 21 measured by the thermocouple 26 and the heat flow rate measured by a heat flowmeter 23.

Description

  The present invention relates to a specific heat measuring device and a specific heat measuring method for a test body, which are designed to measure and calculate the apparent specific heat of a test body, such as a latent heat storage body and other materials.

  In recent years, global warming has progressed globally, and energy saving and suppression of global warming have been promoted by reducing combustion of fossil fuels and exhaust heat to reduce carbon dioxide emissions. The use of solar heat, which is a renewable energy, to reduce carbon dioxide emissions is important in each field. For example, in the field of buildings, in order to reduce energy consumption, heat insulation is arranged on the ceiling, floor, walls, etc., and the absorption and release of latent heat is efficiently controlled to promote the energy saving effect. It has been.

  A latent heat storage material capable of storing and releasing a large amount of heat by phase change has a high energy saving effect and is used in various fields. In particular, in the field of buildings such as buildings and houses, a latent heat storage material is one means of using solar heat, and is known as a material that saves energy for air conditioning and promotes energy saving effects. For example, in the heat storage building material described in Patent Document 1, a base material that becomes a wall material or flooring of a building and a heat storage sheet containing a latent heat storage material are bonded together and used as a building material.

When using latent heat storage materials and other materials as building materials for homes, etc., measure in advance what kind of heat storage performance and heat dissipation performance each type of material has, and how to use it in which location in the home to save energy It is necessary to consider whether it can be effectively demonstrated.
Therefore, for example, a specific heat measuring device 1 shown in FIG. 7 is known as a method for measuring and calculating the apparent specific heat and latent heat amount of various building materials and latent heat storage materials. This specific heat measuring device 1 uses the principle of an adiabatic calorimeter used for measuring the specific heat of a general building material. A latent heat storage material is used as a test body 2 and processed in advance in the center of the test body 2. A junction point of the thermocouple 3 is attached in the formed hole, and the heater 4 is brought into close contact with the outer surface of the test body 2.

  Then, an internal container 5 containing the test body 2 and the heater 4, a heat insulating container 6 installed on the outside thereof, and an external container 7 installed on the outside thereof are further provided. Is installed. The protective heater 8 controls the heating of the space between the heat insulating container 6 and the inner container 5 so as to be the same temperature as the inner space of the inner container 5, and measures the temperature of this space by the differential thermocouple 9 to protect the heater. By performing feedback control of the output of 8 with the heat insulation control device 10, the heat in the inner container 5 is prevented from flowing out to the outside. The specific heat measurement apparatus 1 measures the specific heat in advance using a material with a known specific heat, and calculates the heat capacity of the specific heat measurement apparatus 1 as a calibration heat quantity.

  In the specific heat measurement method using the specific heat measurement device 1, the test body 2 is heated by applying a constant power to the heater 4, and the temperature of the test body 2 is changed from a temperature state lower than the phase change band of the test body 2 to a high temperature state. Control to raise gradually. The heater 4 was heated and controlled by the DC power supply device 11, and the temperature change of the test body 2 measured by the thermocouple 3 was output to the data logger 12, and the apparent specific heat was calculated by the following equation (2).

  Here, the calorific value of the heater 4 is Q (W), the mass of the test body 2 is M (g), the temperature at which the test body 2 rises is Δθ (K), and the time required for the temperature rise of Δθ is Δt (s) The calibration heat quantity is M ′ · c ′ (J / K), and the apparent specific heat c (J / (g · K)) is obtained by the following equation (2). From the apparent specific heat c of the obtained test body 2, the amount of latent heat stored by the phase change can be calculated. The specific heat refers to the amount of heat required to raise the temperature of the material by 1 ° C. as a value per unit of material, and the apparent specific heat refers to a value obtained by adding the amount of latent heat to this specific heat. .

JP 2001-173118 A

  However, the specific heat measuring apparatus 1 using the heater 4 and the protective heater 8 described above can measure the apparent specific heat in the region where the temperature of the test body 2 increases and the phase changes, but the temperature of the test body 2 decreases. In the region where the phase changes, since the temperature cannot be adjusted by the heater 4 and the protective heater 8 that control the heating temperature, there is a drawback that the apparent specific heat cannot be measured. On the other hand, in many building materials including latent heat storage materials, latent heat storage materials are often mixed with other general building materials, not only the change in heat absorption when the temperature rises, but also the amount of heat released when the temperature drops. Change is also an important factor. Therefore, if the apparent specific heat and heat storage amount due to the phase change at the time of temperature drop cannot be measured, there is a drawback that the heat absorption characteristics and heat radiation characteristics of building materials and various materials including the latent heat storage material cannot be grasped.

  The present invention has been made in view of such circumstances, and provides a specific heat measurement device and a specific heat measurement method for a test specimen that can measure the apparent specific heat at the time of temperature rise and temperature drop of various specimens. The purpose is to do.

A specific heat measuring apparatus for a test body according to the present invention includes a test body, a heating member having a fluid for raising and lowering the temperature of the test body, a heat flow meter disposed between the test body and the heating member, and the test body. And a thermocouple that measures the temperature of the specimen, and the apparent specific heat of the specimen is calculated based on the temperature of the specimen measured by the thermocouple and the heat flow rate measured by the heat flow meter. .
The specific heat measuring device for a test body according to the present invention includes a fluid capable of raising and lowering the temperature in the heating member, so that the temperature of the heating member can be raised and lowered by the fluid and transmitted to the test body through a heat flow meter. It is possible to store the heat by changing the phase by increasing the temperature of the specimen, and to dissipate the heat by changing the phase by lowering the temperature of the specimen, so the temperature and heat flow of the specimen measured with a thermocouple Based on the heat flow measured by the meter, it is possible to measure and calculate the apparent specific heat of the specimen when the temperature rises and when the temperature falls.

In addition, a constant temperature fluid supply means for raising and lowering the temperature of the fluid circulated through the heating member is provided, and the constant temperature fluid supply means includes a heating means for raising the fluid over the temperature before and after the phase change, and a phase change of the fluid. It is preferable to provide cooling means for lowering the temperature before and after the temperature.
When the temperature rises, the temperature of the fluid is raised by the heating means of the constant temperature fluid supply means, supplied to the heating member and circulated, so that the temperature of the heating member can be raised and transmitted to the test body. The temperature of the fluid is lowered by the cooling means of the constant temperature fluid supply means, supplied to the heating member and circulated, so that the temperature of the heating member can be lowered and transmitted to the specimen.

Moreover, it is preferable to provide a constant temperature and humidity chamber that accommodates the test body, the heating member, and the heat flow meter and controls the internal atmosphere temperature to be equal to the temperature of the fluid.
The test body, heating member, and heat flow meter are housed in a constant temperature and humidity chamber, and the internal atmosphere temperature is controlled to be equal to the temperature of the fluid. Can communicate to.

Moreover, it is preferable that a test body consists of a several test body piece which pinches | interposes a thermocouple.
By dividing the test body into a plurality of test body pieces and putting them in close contact with a thermocouple, the center temperature can be measured with the thermocouple without processing the test body.

Moreover, it is preferable to calculate the apparent specific heat in the step of raising the specimen by raising the temperature of the specimen before and after the phase change by the constant temperature fluid supply means.
By increasing the temperature of the fluid circulated to the heating member by the constant temperature fluid supply means, the temperature of the test body transmitted from the heating member via the heat flow meter rises, and the heat flow becomes maximum in the phase change region of the test body, The apparent specific heat in the ascending process of the specimen can be measured based on the measured value of the temperature of the specimen and the temperature of the heat flow meter by the thermocouple.

In addition, it is preferable to calculate the apparent specific heat in the lowering process of the specimen by lowering the temperature of the specimen before and after the phase change by the constant temperature fluid supply means.
By lowering the temperature of the fluid circulated to the heating member by the constant temperature fluid supply means, the temperature of the test body transmitted from the heating member via the heat flow meter is lowered, and the heat flow is minimized in the phase change region of the test body, The apparent specific heat in the descending process of the test body can be measured based on the measured value of the temperature of the test body and the temperature of the heat flow meter by the thermocouple.

但し、ｃ：見かけの比熱（J／（ｇ・Ｋ））、ｑ：熱流量（Ｗ/ｍ^２ ）、Ａ：試験体の面積、Ｍ：試験体の質量（ｇ）、Δθ：試験体の上昇または降下する温度値（Ｋ）、Δｔ：試験体がΔθの温度上昇または降下に要する時間。 In addition, the apparent specific heat of the specimen can be calculated by the following equation (1).

Where c: apparent specific heat (J / (g · K)), q: heat flow rate (W / m ² ), A: area of specimen, M: mass (g) of specimen, Δθ: of specimen Temperature value to rise or fall (K), Δt: Time required for the specimen to rise or fall by Δθ.

Further, the test body may be a latent heat storage material.
If the test body is a latent heat storage material, the latent heat can be stored during the phase change in the temperature increasing process, and the latent heat stored during the phase change in the decreasing process can be released.

The specific heat measurement method for a test specimen according to the present invention is a method for measuring the temperature of a test specimen before and after a phase change by increasing the temperature of the specimen by a fluid flowing through the heating member in the temperature raising step. Measure the heat flow transferred to the body,
In the temperature lowering step, the temperature of the test body is lowered by the fluid flowing through the heating member to measure the temperature of the test body before and after the phase change, and the heat flow transferred from the heating member to the test body is measured,
Based on the measured temperature and heat flow of the specimen, the apparent specific heat of the specimen at the time of temperature rise and fall is calculated.
According to the specific heat measuring method of the test body according to the present invention, the temperature of the heating member that transfers heat to the test body is raised and lowered, and based on the measured temperature and heat flow of the test body, respectively. The apparent specific heat of the test body in the temperature raising process and the temperature lowering process can be calculated. Further, the latent heat storage amount can be calculated by integrating the apparent specific heat.

但し、ｃ：見かけの比熱（J／（ｇ・Ｋ）、ｑ：熱流量（Ｗ/ｍ^２ ）、Ａ：試験体の面積、Ｍ：試験体の質量（ｇ）、Δθ：試験体の上昇または降下する温度値（Ｋ）、Δｔ：試験体がΔθの温度上昇または降下に要する時間。 In addition, the apparent specific heat of the specimen can be calculated by the following equation (1).

However, c: Apparent specific heat (J / (g · K), q: Heat flow rate (W / m ² ), A: Area of specimen, M: Mass (g) of specimen, Δθ: Increase of specimen Or temperature value (K) which falls, (DELTA) t: Time which a test body requires for temperature rise or fall of (DELTA) (theta).

  According to the specific heat measuring device and the specific heat measuring method according to the present invention, by raising and lowering the temperature of the heating member with a fluid, it is possible to increase and decrease the temperature in the region before and after the phase change of the test specimen. It is possible to calculate the apparent specific heat and heat storage amount of the test body in the temperature raising process and the temperature lowering process, and to inspect the heat storage and heat dissipation characteristics of the test body.

It is a figure which shows the principal part structure of the apparent specific heat measuring apparatus by embodiment of this invention. It is a front view which shows the state which attached the thermocouple to the inner surface of one test piece. It is a graph which shows the measured value of the test body center temperature measured with the specific heat measuring apparatus in embodiment of this invention, a heating plate temperature, and the heat flow from a heating plate to a test body. It is a graph which shows the relationship between the test body center temperature and the apparent specific heat in the temperature decreasing process of the test body center temperature shown in FIG. It is a graph which shows the test body center temperature and heater temperature at the time of the temperature rise in the conventional specific heat measuring apparatus. It is a graph which shows the apparent specific heat by the conventional measuring apparatus at the time of a temperature rise, and the apparent specific heat by the measuring apparatus of embodiment. It is a figure which shows the principal part structure of the apparent specific heat measuring apparatus by a prior art example.

Hereinafter, an apparent specific heat measuring device and a specific heat measuring method according to an embodiment of the present invention will be described with reference to FIGS.
The apparent specific heat measuring apparatus 20 according to the present embodiment heats and cools the test body 21 on the outer surfaces 21b on both sides of the test body 21, for example, which is a measurement target as shown in FIG. A heating plate 22 is provided as a heating member to be generated. For example, sheet-like heat flow meters 23 are disposed in close contact with each other between the outer surfaces 21 b of the test body 21 and the respective heating plates 22. The heat flow meter 23 transmits a heat flow from the heating plate 22 to the test body 21, thereby measuring a temperature difference generated on both surfaces of the heat flow meter 23 as a heat flow rate to the test body 21. The test body 21, the pair of heating plates 22, and the pair of heat flow meters 23 constitute a test apparatus 24, and the test apparatus 24 is installed in a constant temperature and humidity chamber 25 sealed with a housing.

  The test body 21 is composed of, for example, two test body pieces 21a having a plate shape of the same shape and the same size, and a thermocouple 26 for measuring the temperature of the inner surface 21c is closely attached between the test body pieces 21a. ing. The thermocouple 26 is set at three points of the center of the inner surface 21c and the two outer surfaces 21b that are in contact with each other, and two points are measured at each point to obtain an average value as a measured value. In the inner surface 21c of the test piece 21a shown in FIG. 2, the junction points 26a and 26b of the thermocouple 26 are installed at two points at a position slightly deviated from the center. Thereby, the temperature in the center of the test body 21 can be measured by an average value of two points. Further, by bonding two test piece pieces 21a as the test piece 21, the center temperature can be measured without drilling the test piece 21.

  For the test body 21, for example, a test piece 21a was formed by filling a plastic container with a heat storage material mainly composed of sodium sulfate decahydrate and forming it into a plate-shaped building material. As the test body 21, paraffin can be microencapsulated and mixed with other materials. Or it is not limited to these latent heat storage materials, You may employ | adopt other materials, for example, the plywood used for building materials, a gypsum board, etc.

  Further, the pair of heating plates 22 are connected to a constant temperature water tank 28 installed outside the constant temperature and humidity chamber 25 through a pipe 27. For example, water is stored as a circulating fluid that is a fluid in the constant temperature water tank 28, and is circulated between the heating plate 22 via a pipe 27. In addition, the constant temperature water tank 28 is provided with a heater as a heating means and a refrigerator (not shown) as a cooling means in order to raise or lower the temperature of the circulating fluid, and when the temperature rises and falls The temperature of the heating plate 22 is managed to be adjustable. In the heating plate 22, for example, a pipe 27 is curved in a meandering state, and a circulating liquid having a predetermined temperature is circulated to control the temperature of the heating plate 22 uniformly.

Further, for example, an air conditioner (not shown) is installed in the constant temperature and humidity chamber 25 as a temperature adjusting means, and the temperature in the constant temperature and humidity chamber 25 is controlled by the control unit 29 so as to coincide with the temperature in the constant temperature water tank 28. Yes. Thus, the heat of the heating plate 22 is controlled to be transmitted to the test body 21 without being transmitted to the air in the constant temperature and humidity chamber 25.
In addition, the measured value of the temperature of the test body 21 by the thermocouple 26 and the measured value of the heat flow rate from the heating plate 22 to the test body 21 by the heat flow meter 23 are transmitted to the data logger 30 via the wiring, and apparent The specific heat c is calculated by the following equation (1). Moreover, the heat storage amount of the test body 21 can be calculated by integrating the apparent specific heat c with temperature.

但し、ｃ：試験体２１の見かけの比熱（J／（ｇ・Ｋ））、ｑ：熱流計２３で測定した熱流量（Ｗ/ｍ^２ ）、Ａ：試験体２１の面積、Ｍ：試験体２１の質量（ｇ）、Δθ：試験体２１の上昇または降下する温度値（Ｋ）、Δｔ：試験体２１がΔθの温度上昇または降下に要する時間。

However, c: Apparent specific heat (J / (g · K)) of the test body 21, q: Heat flow rate (W / m ² ) measured by the heat flow meter 23, A: Area of the test body 21, M: Test body 21 mass (g), Δθ: temperature value (K) at which the specimen 21 rises or falls, Δt: time required for the specimen 21 to rise or fall at Δθ.

The apparent specific heat measuring device 20 according to the present embodiment has the above-described configuration, and an apparent specific heat measuring method will be described next.
First, as the test body 21, for example, two test body pieces 21 a filled with sodium sulfate decahydrate specified in Table 1 below in a plastic container are brought into close contact with each other with the inner surface 21 c sandwiched between the thermocouples 26. The heating plates 22 are brought into close contact with 21 b through the heat flow meter 23. Then, the test apparatus 24 including the test body 21 is enclosed in a constant temperature and humidity chamber 25, and the test apparatus 24 including the test body 21 is cured near 0 ° C. lower than the phase change temperature before the test. Stabilize.

Then, the circulating fluid heated in the constant temperature water tank 28 is circulated in the heating plate 22 in the constant temperature and humidity chamber 25 through the pipe 27 to raise the temperature of the heating plate 22 and in the constant temperature and humidity chamber 25. Is controlled to the same temperature as the circulating fluid in the constant temperature bath 28. As a result, the temperature of the heating plate 22 is controlled to be substantially the same as the temperature of the constant temperature water bath 28 and the temperature of the constant temperature and humidity chamber 25.
In the temperature raising step, in order to raise the temperature of the test body 21 at a constant speed, the temperature of the constant temperature water tank 28 is raised at a constant speed, the temperature of the heating plate 22 is raised via the pipe 27, and the heat flow meter 23 is used. Is transmitted to the test body 21. Then, the temperature of the test apparatus 24 including the test body 21 is gradually increased, and is increased until the temperature of the test body 21 reaches 60 ° C., for example, exceeding the phase change temperature within the range of 20 ° C. to 30 ° C. It was.

Next, in the temperature lowering step, for example, the test device 24 is cured at around 60 ° C., the temperature of the circulating fluid in the constant temperature water tank 28 is lowered by a refrigerator, and the circulating fluid whose temperature has been lowered is conveyed to the heating plate 22 through the pipe 27. The temperature of the heating plate 22 is lowered. At the same time, the temperature in the constant temperature and humidity chamber 25 is lowered by an air conditioner so as to be substantially the same as the temperature of the circulating fluid in the constant temperature water tank 28, and the temperature of the heating plate 22 is transmitted to the test body 21 via the heat flow meter 23. The
And the temperature of the test body 21 transmitted via the heating plate 22 falls gradually from 60 degreeC by lowering | hanging the atmospheric temperature of the constant temperature water tank 28 and the constant temperature and humidity chamber 25 gradually, and the range of 20 to 30 degreeC The temperature of the test body 21 was lowered to 0 ° C. beyond the temperature in the phase change region.

  According to the specific heat measuring method by the specific heat measuring apparatus 20 of the present embodiment, the temperature of the center of the test body 21 is measured by the thermocouple 26 at predetermined time intervals in the temperature raising step and the temperature lowering step, and the temperature of the heating plate 22 is measured. The heat flow from the heating plate 22 to the test body 21 was measured with a heat flow meter 23. As a result, the result shown in FIG. 3 was obtained.

In FIG. 3, the “heating plate temperature”, which is the temperature of the heating plate 22, rises uniformly from 0 ° C. to 60 ° C. in the temperature raising process, and after curing at around 60 ° C., to 0 ° C. It descended uniformly. The “test body center temperature”, which is the center temperature of the test body 21, shows a tendency that the slope gradually changes in the phase change region of 20 ° C. to 30 ° C. in the temperature raising step. Even in the temperature lowering process, the “center temperature of the specimen” changes with a uniform downward slope, and heat generation from the specimen 21 is observed near 30 ° C. in the phase change region. As a result, the line shape of the graph was different from that of the temperature raising step.
Regarding the “test body center temperature” shown in FIG. 3, the hump-like heat generation portion in the temperature lowering process is a unique phenomenon only seen in the test body 2 employed in the present embodiment, but the temperature drop including the hump-like heat generation portion is included. When the amount of heat was integrated based on the average value of the temperature data of the process, data indicating the relationship between the average value of the test specimen center temperature and the apparent specific heat shown in FIG. 4 was obtained.
The apparent specific heat in the temperature lowering step of FIG. 4 has a peak of 45 J / gK when the center temperature of the specimen is around 25 ° C., and corresponds to the hump portion shown in FIG. The test body 2 in the present embodiment exhibits completely different characteristics when the temperature is raised and when the temperature is lowered, and such a result is considered to result from the blending of the latent heat storage material used.

  Further, the “heat flow rate” measured by the heat flow meter 23 increases as the difference between the “heating plate temperature” and the “test body center temperature” increases, and the center temperature of the test body 21 ranges from 20 ° C. to 30 ° C. It became the maximum in the phase change region. In the temperature lowering process, the difference between the “heat flow rate” and the “test body center temperature” is the maximum in the phase change region where the center temperature of the test body 21 is 20 ° C. to 30 ° C., and the “heat flow rate” is the minimum. became.

On the other hand, in the specific heat measuring method by the specific heat measuring apparatus 1 of the prior art shown in FIG. 7, the same specimen as the specimen 21 according to the present embodiment is used as the specimen 2, and two specimen pieces are thermocoupled. Measurement was conducted with 3 being in close contact with each other. This specific heat measurement method was performed by the same measurement method as described in the section of the prior art.
That is, the temperature of the space between the inner container 5 and the heat insulating container 6 was controlled to be the same by the protective heater 8 so that the heating temperature of the heater 4 was transmitted to the test body 2 without loss. Then, the temperature of the protective heater 8 and the temperature of the heater 4 are raised from the curing state of 0 ° C., the temperature of the test body 2 is raised through the phase change region, and the temperature is raised to about 60 ° C.

  FIG. 5 shows the time change between the “test body center temperature” measured by the thermocouple 3 and the “heater temperature” which is the temperature of the heater 4. The “test body center temperature” has a gentle gradient between 20 ° C. and 30 ° C., and it is recognized that heat storage due to phase change occurs in the test body 2. Although the electric power applied to the heater 4 is constant, the temperature is pulled by the latent heat storage effect of the test body 2, so that the “heater temperature” also changes along the “test body center temperature”.

  And the specific heat measurement method by the specific heat measurement device 20 according to the embodiment is B, and the specific heat measurement method by the conventional specific heat measurement device 1 is A, and the temperature measurement value in the temperature raising process of the “test body center temperature” is stable. FIG. 6 is a graph showing the result of calculating the apparent specific heat obtained by dividing the temperature increase (Δθ) every 1K in the range of 5 ° to 55 ° C. that can be regarded as 5 ° C. to 55 ° C. according to the above equations (1) and (2). As shown.

In the conventional specific heat measurement method A shown in FIG. 6 and the specific heat measurement method B of the embodiment, the apparent specific heat is somewhat different in relation to the temperature, but both occur in the range of 20 ° C. to 30 ° C. The tendency of the change also shows a similar curve characteristic. Moreover, the specific heats of the test bodies 2 and 21 are substantially the same in the regions on both sides excluding the phase displacement region in the range of 20 ° C. to 30 ° C.
Therefore, the change in the apparent specific heat of the “specimen center temperature” in the specific heat measurement apparatus 20 according to the present embodiment exhibits substantially the same curve characteristics as the change in the apparent specific heat by the conventional specific heat measurement apparatus 1 whose evaluation has been determined. It can be recognized that the specific heat measuring apparatus 20 and the specific heat measuring method B according to the present embodiment exhibit correct characteristics.

Next, the amount of heat stored in the test body 21 can be calculated by integrating the apparent specific heat of the test body 21 obtained by the equation (1) with temperature. The latent heat storage amount can be calculated by subtracting the sensible heat component from this heat storage amount.
Further, as a trial, the average value of the apparent specific heat in the range where the “test body center temperature” is in the range of 5 ° C. to 15 ° C. is set as a representative value of the specific heat of the test bodies 2 and 21 by sensible heat, and the phase displacement region is 20 ° C. The apparent specific heat in the range of ˜30 ° C. was calculated from the formulas (1) and (2), and the heat storage amount of the test bodies 2 and 21 and the latent heat storage amount of the test bodies 2 and 21 were calculated. Further, the apparent volume specific heat, the amount of stored heat, and the amount of stored latent heat were also calculated, and the calculation results are shown in Table 2.

As described above, according to the specific heat measurement apparatus 20 according to the present embodiment, the apparent specific heat with respect to the temperature in the temperature raising step exhibits the same numerical value and change characteristics as the apparent specific heat of the conventional specific heat measurement apparatus 1, and thus the apparent specific heat. It is recognized that the specific heat can be calculated accurately.
Moreover, in this embodiment, without using the heater 4 or the protective heater 8 as the heating means, the heating and cooling of the circulating fluid circulating to the heating plate 22 in the constant temperature water tank 28 is freely controlled to control the temperature increase and the temperature decrease. Therefore, the apparent specific heat in the temperature raising step in FIG. 6 and the apparent specific heat in the temperature lowering step (see FIG. 4) that could not be measured conventionally can be measured and calculated, and the apparent specific heat can be measured and calculated for any specimen 21. .

Moreover, the center temperature can be measured as the test body 21 by simply bonding the two test body pieces 21a across the junction of the thermocouple 26 without drilling the center. Therefore, apparent specific heat and latent heat storage amount can be easily measured and calculated not only for latent heat storage materials but also for general materials such as plywood and gypsum board.
In addition, since the test apparatus 24 including the test body 21 is installed in the constant temperature and humidity chamber 25 and the internal atmosphere temperature is controlled to be the same as the temperature of the circulating fluid in the constant temperature water tank 28, The measurement deviation due to the heat escape from the heat and the heat capacity of the test device 24 can be corrected, and the temperature of the heating plate 22 can be prevented from escaping to the outside and can be transmitted to the test body 21, so that a measurement error hardly occurs.
In addition, since the constant temperature and humidity chamber 25 is provided and the ambient temperature around the test device 24 can be controlled almost the same as the temperature of the circulating fluid, the heat insulating container 6 provided in the conventional specific heat measuring device 1 is not necessary, Simpler configuration and higher measurement accuracy.

In the above-described embodiment, the test apparatus 24 including the test body 21 is accommodated in the constant temperature and humidity chamber 25, and the atmospheric temperature is controlled to be the same as the temperature of the circulating liquid in the constant temperature water tank 28. The ambient temperature around the test device 24 may be controlled to the same temperature as the circulating liquid in the constant temperature water tank 28 by using an air conditioner, a heater, or the like without providing the air conditioner 25.
Further, water is used as a circulating fluid for circulating the constant temperature water tank 28, the pipe 27, and the heating plate 22. However, any fluid that can increase and decrease the temperature by heating means such as a heater and can transfer heat to the heating plate 22 is used. Liquids other than water, gases, and the like may be used.
The constant temperature water tank 28 constitutes a constant temperature fluid supply means.
Moreover, although the two test piece 21a was bonded as the test piece 21 across the junction of the thermocouple, the test piece 21a may be composed of three or more pieces.

20 Specific Heat Measuring Device 21 Specimen 21a Specimen Piece 22 Heating Plate 23 Heat Flow Meter 25 Constant Temperature and Humidity Chamber 26 Thermocouple 27 Pipe 28 Constant Temperature Water Tank 30 Data Logger

Claims (10)

A specimen,
A heating member having a fluid that transfers heat to the specimen to raise and lower the temperature of the specimen;
A heat flow meter provided between the test body and the heating member;
A thermocouple for measuring the temperature of the specimen,
A specific heat measurement apparatus for a test specimen, wherein the apparent specific heat of the test specimen is calculated based on the temperature of the specimen measured by the thermocouple and the heat flow rate measured by the heat flow meter.   There is provided a constant temperature fluid supply means for increasing and decreasing the temperature of the fluid circulated through the heating member, and the constant temperature fluid supply means includes a heating means for increasing the fluid over the temperature before and after the phase change, and a phase change of the fluid. The specific heat measuring device for a test specimen according to claim 1, further comprising cooling means for lowering the temperature before and after the temperature.   3. The specific heat measuring device for a test body according to claim 1, further comprising a constant temperature and humidity chamber that accommodates the test body, a heating member, and a heat flow meter and controls an internal atmosphere temperature to be equal to a temperature of the fluid. .   The specific heat measuring apparatus for a test body according to any one of claims 1 to 3, wherein the test body includes a plurality of test body pieces sandwiching the thermocouple.   5. The apparent specific heat in the temperature raising step of the test body is calculated by increasing the temperature of the test body before and after the phase change by the constant temperature fluid supply means. The specific heat measuring device of the test body described in the paragraph.   6. The apparent specific heat in the temperature lowering step of the test body is calculated by lowering the temperature of the test body before and after the phase change by the constant temperature fluid supply means. The specific heat measuring device of the test body described in 1. The specific heat measuring device of the test body according to any one of claims 1 to 6, wherein an apparent specific heat of the test body is measured by the following equation (1).

However, c: Apparent specific heat (J / (g · K), q: Heat flow rate (W / m ² ), A: Area of specimen, M: Mass (g) of specimen, Δθ: Increase of specimen Or temperature value (K) which falls, (DELTA) t: Time which a test body requires for temperature rise or fall of (DELTA) (theta).   The specific heat measuring apparatus for a test body according to any one of claims 1 to 7, wherein the test body is a latent heat storage material. In the temperature raising step, the temperature of the test body is increased by the fluid flowing through the heating member to measure the temperature of the test body before and after the phase change, and is transmitted from the heating member to the test body via the heat flow meter. Measure the heat flow
In the temperature lowering step, the temperature of the test body is lowered by the fluid flowing through the heating member to measure the temperature of the test body before and after the phase change, and is transmitted from the heating member to the test body through a heat flow meter. Measured heat flow,
A specific heat measurement method for a specimen, wherein an apparent specific heat of the specimen at the time of temperature rise and drop is calculated based on the measured temperature and heat flow of the specimen. The specific heat measurement method of the test body described in claim 9, wherein the apparent specific heat of the test body is calculated by the following equation (1).

However, c: Apparent specific heat (J / (g · K), q: Heat flow rate (W / m ² ), A: Area of specimen, M: Mass (g) of specimen, Δθ: Increase of specimen Or temperature value (K) which falls, (DELTA) t: Time which a test body requires for temperature rise or fall of (DELTA) (theta).

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