JP2006145446A - Thermal conductivity measuring device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal conductivity measuring device capable of measuring contact thermal resistance Rc and thermal conductivity k<SB>u</SB>with sufficient accuracy by realizing an ideal one-dimensional thermal conduction along the z direction alone through prevention for heat leakage from the peripheries of a rod and an object to be measured. <P>SOLUTION: In the thermal conductivity measuring device, after an object 23 to be measured is interleaved between a rod 21 on a heating side and a rod 22 on a cooling side, by flowing heat quantity inward or outward through the rod 21 on the heating side, the object 23 to be measured, and the rod 22 on the cooling side, thermal conductivity of the object 23 to be measured or contact thermal resistance between the rods 21 and 22 and the object 23 to be measured can be measured, a plurality of compensating heaters 32 are deployed on the periphery of the rod 21 on the heating side, the rod 22 on the cooling side, and the object 23 to be measured and the heating value of the compensating heaters 32 is controlled so as to equalize the temperature of each compensating heaters 32 and the temperatures of the rod 21 on the heating side, the rod 22 on the cooling side, and the object 23 to be measured at the same height as the temperature measuring point of the each aforementioned compensate heater 32. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In this invention, a measurement object is sandwiched between a heating side rod and a cooling side rod, and heat is transmitted through the heating side rod, the measurement object and the cooling side rod, and the thermal conductivity of the measurement object or the rod and the measurement object are measured. The present invention relates to a thermal conductivity measuring device for measuring contact thermal resistance between a body and a method for measuring thermal conductivity.

FIG. S. It is a block diagram of the thermal conductivity measuring device disclosed in the paper Themal Conductance of Multilayered Metalic Sheets (AIAA26th Thermophysics Conference, June 24-26, 1991 / Honolulu Hawaii) published by Frether et al. In the measuring apparatus of FIG. 8, a heating side rod 21 and a cooling side rod 22 having a known thermal conductivity k _rot are previously provided above and below the measured object 23, and the uppermost portion of the heating side rod 21 is heated by the heating block 11. The lowermost part of the cooling side rod 22 is cooled by the cooling block 12. Holes are provided in the heating side rod 21 and the cooling side rod 22 at predetermined intervals for measuring the temperature distribution, and temperature measuring sensors 41 and 42 constituted by thermocouples are embedded in the holes. ing. In addition, an additional force device 15 for controlling the contact surface pressure between the rods 21 and 22 and the measured object 23 is disposed above the heating block 11, and a load cell 13 is installed for measuring the contact surface pressure. Has been.

  The measurement principle of contact thermal resistance using the thermal conductivity measuring device of FIG. 8 is as follows. Here, the cross-sectional areas of the two rods 21 and 22 and the measured object 23 are the same, but the cross-sectional shape is not limited.

  The heat flux q flowing from the heating block 11 into the heating side rod 21, passing through the measured object 23, flowing out from the cooling side rod 22, and flowing into the cooling water passing through the cooling block 12 is expressed by the following (Equation 1). Can be obtained from

Here, q ₁ : heat flux (W / m ² ) flowing from the heating side rod 21 into the measured object 23,
q _{2 is} the heat flux (W / m ² ) flowing into the cooling side rod 22 from the measured object 23 and is given by the following (Expression 2) and (Expression 3).

Therefore, the contact thermal resistance R _c between the two rods 21 and 22 is obtained by (Equation 4) from the measured temperature gradient of the two rods 21 and 22.

Further, the contact thermal resistance R _c depends on the contact pressure between the two rods 21 and 22 and the measured object 23. Therefore, using the additional force device 15 and the load cell 13, the temperature gradient is measured for each predetermined pressure value while varying the contact pressure between the two rods 21, 22 and the measured object 23, and the contact heat is measured. The resistance _Rc is obtained.

Then, if you want to see the thermal conductivity k _u of the object to be measured 23, buried temperature measurement sensor consists of a thermocouple into a hole provided in the object to be measured 23 with a thickness z-axis direction, the object to be measured A temperature gradient in the z-axis direction of 23 is measured. At this time, the heat flux q passing through the measurement object 23 is defined by (Equation 5).

Therefore, the thermal conductivity k _u of the measured object 23 is obtained by (Equation 6) using the temperature gradient of the measured object 23.

Incidentally, when calculating the thermal conductivity k _u of the object to be measured 23, the temperature gradient in the case where the z-axis direction of the thickness of the object to be measured 23 can not embedded thermocouple little holes, z-axis direction of the object to be measured 23 May be obtained by ΔT in (Equation 4) (temperature difference obtained from the extrapolated line of each temperature gradient in the two rods) and substituted into (Equation 6).

  As described above, if the thermal conductivity measuring device of FIG. 8 is used, it is possible to measure contact thermal resistance and thermal conductivity.

  Conventionally, as a temperature predicting device for cocrete, a cylindrical heat insulating tank provided with a peripheral wall that forms a concrete placement space inside and holds four surrounding surfaces in a heat-insulated state, and is placed in this heat insulating tank. A temperature detector for detecting the history temperature of the concrete, a casing for covering both openings of the heat insulation tank and forming a temperature control space therein, and a control means for controlling the temperature in the casing (For example, Patent Document 1).

L. S. "Themal Conductance of Multilayered Metalic Sheets" by Frether et al. (AIAA26th Thermophysics Conference, June 24-26, 1991 / Honolulu Hawaii) JP 63-117249 A (Claim 1, FIG. 1)

Turning now in the non-patent document (Expression 4) and (6), the accuracy of the measured value of the thermal contact resistance R _c and the thermal conductivity k _u is the temperature of the rod 21, 22 or the object to be measured 23 It can be seen that this greatly affects the accuracy of the gradient measurement. Therefore, at the time of measurement, the rod 21 and 22 or the object to be measured 23 is measured from the rod 21 so that the temperature in the cross section with the z axis as the normal is uniform and the temperature gradient is measured as an ideal linear line. It is desirable to realize heat conduction only in the z-axis direction to the body 23 and the rod 22. 8 may be installed in a vacuum environment to prevent heat leakage from the rods 21 and 22 and the measured object 23 in directions other than the z-axis. It takes a lot of labor.

In addition, there is a method in which the outer circumferences of the rods 21 and 22 and the measured object 23 are covered with a heat insulating material, and the temperature distribution of the rods 21 and 22 and the measured object 23 when actually using the method is shown in FIG. Shown in In FIG. 9, the horizontal axis indicates the temperature measurement point of the rod or the object to be measured, and the vertical axis indicates the temperature. The plot is an actual measurement value, and the straight line is an approximate straight line based on the actual measurement value. At this time, even if one-dimensional heat conduction only in the z-axis direction is realized, heat leakage through the heat insulating material exists, so that the temperature gradient of the rods 21 and 22 or the measured object 23 is actually as shown in FIG. It is not an ideal linear straight line. This causes the accuracy deterioration of the thermal conductivity k _u represented by the thermal contact resistance R _c and is expressed by (Equation 4) (Equation 6).

  In Patent Document 1, the temperature in the cross section with the z-axis of the concrete as the normal is uniform and the temperature gradient is an ideal linear line, that is, the temperature in the concrete at the same position and the temperature in the casing. It is not disclosed that the heater is controlled so that the temperatures are the same.

The present invention has been made to solve the above-described conventional problems, and does not require much labor, prevents heat leakage from the outer periphery of the rod and the object to be measured, and is ideal only in the z-axis direction. achieve specific one-dimensional heat conduction, and an object thereof is to provide a thermal conductivity measuring device can be accurately measured thermal contact resistance Rc and thermal conductivity k _u.

  A thermal conductivity measuring apparatus according to the present invention includes a heating side rod and a cooling side rod that sandwich a measured object therebetween, and allows heat to flow from a side that does not contact the measured object of the heating side rod, Calculate the amount of heat input to the measured object by letting the heat flow out from the side not contacting the measured object of the cooling side rod through the measured object and the cooling side rod, and measuring the temperature gradient in both rods. A thermal conductivity measuring device for measuring a thermal conductivity of a measured object or a contact thermal resistance between the rod and the measured object from a measured amount of heat and a temperature gradient of the measured object, comprising a heating side rod, a cooling side rod, A plurality of compensation heaters are arranged on the outer circumference of the object to be measured, and the temperature of each compensation heater and the temperature of the heating side rod, the cooling side rod, and the object to be measured at the same height as the temperature measurement point of each compensation heater are To be equal, Wherein the heating value of amortization heater is controlled.

  Further, the thermal conductivity measuring device according to the present invention includes a heating side rod and a cooling side rod for sandwiching a measured object therebetween, and allows the amount of heat to flow from the side not contacting the measured object of the heating side rod. The amount of heat input to the measured object is calculated by letting the heat flow out from the side not contacting the measured object of the cooling side rod through the rod, measured object and cooling side rod, and measuring the temperature gradient in both rods. , A thermal conductivity measuring device for measuring the thermal conductivity of the measured object or the contact thermal resistance between the rod and the measured object from the calculated heat quantity and the temperature gradient of the measured object, the heating side rod and the cooling side A plurality of compensation heaters are arranged on the outer periphery of the rod, so that the temperature of each compensation heater is equal to the temperature of the heating side rod and the cooling side rod at the same height as the temperature measurement point of each compensation heater. Compensation Wherein the heating value of the motor is controlled.

  Further, the method for measuring the thermal conductivity according to the present invention includes a step of sandwiching the measurement object between the heating side rod and the cooling side rod, and the temperature of the outer circumference of the heating side rod, the cooling side rod and the measurement object. The heating side rod positioned at the same height, the cooling side rod and the step of controlling to be equal to the temperature of the measured object itself, and the amount of heat flowing from the side of the heated side rod not contacting the measured object, The amount of heat input to the measured object is calculated by letting the heat flow out from the side not contacting the measured object of the cooling side rod through the rod, measured object and cooling side rod, and measuring the temperature gradient in both rods. And measuring the thermal conductivity of the measured object or the contact thermal resistance between the rod and the measured object from the calculated heat quantity and the temperature gradient of the measured object.

  In addition, the method for measuring thermal conductivity according to the present invention includes the step of sandwiching the object to be measured between the heating side rod and the cooling side rod, and the temperatures of the outer circumferences of the heating side rod and the cooling side rod at the same level. A step of controlling the heating side rod and the cooling side rod itself to be equal to the temperature of the heating side rod, and a heat amount from the side of the heating side rod that does not come into contact with the measured body, Calculate the amount of heat input to the measured object by measuring the temperature gradient in both rods by letting the heat flow out from the side of the cooling side rod that does not come into contact with the measured object through the rod. And measuring the thermal conductivity of the object to be measured or the contact thermal resistance between the rod and the object to be measured from the temperature gradient.

  According to the thermal conductivity measuring device of the present invention, a plurality of compensation heaters are arranged on the outer circumference of the heating side rod, the cooling side rod, and the measured object, respectively, the temperature of each compensation heater, the temperature measurement point of each compensation heater, Since the heating value of the compensation heater is controlled so that the temperature of the heating side rod, cooling side rod, and measured object at the same height is equal, the surroundings from the heating side rod, cooling side rod, or measured object The amount of heat leaked in the direction can be reduced, and the amount of heat that has flowed in can be transmitted in a one-dimensional manner from the heating rod to the cooling rod through the object to be measured. Rise.

  According to the thermal conductivity measuring device of the present invention, a plurality of compensation heaters are arranged on the outer circumferences of the heating side rod and the cooling side rod, respectively, and the temperature of each compensation heater is the same as the temperature measurement point of each compensation heater. The amount of heat generated by the compensation heater is controlled so that the temperature of the heating side rod and cooling side rod at the same level is controlled, so the amount of heat leakage from the heating side rod and cooling side rod to the surrounding direction is reduced. Since the amount of heat that has flowed in can be transmitted one-dimensionally from the heating side rod to the cooling rod through the measured object, the accuracy of the measured value of the thermal conductivity of the measured object increases.

  Further, according to the method of measuring thermal conductivity of the present invention, the heating side rod, the cooling side rod, and the measured object are positioned at the same height as the temperature of the outer circumference of the heating side rod, the cooling side rod, and the measured object. Since the temperature is controlled to be equal to its own temperature, the amount of heat leakage from the heating side rod, cooling side rod or measured object to the surrounding direction can be reduced, and the amount of inflowed heat is cooled from the heated side rod through the measured object. Since it can be transmitted to the rod in one dimension, the accuracy of the measured value of the thermal conductivity of the object to be measured is increased.

  Further, according to the method of measuring the thermal conductivity of the present invention, the temperature of the outer circumference of the heating side rod and the cooling side rod is made equal to the temperature of the heating side rod and the cooling side rod itself located at the same height. Since it is controlled, the amount of heat leakage from the heating side rod and the cooling side rod to the surrounding direction can be reduced, and the amount of heat that flows in can be transmitted in a one-dimensional manner from the heating side rod to the cooling rod through the object to be measured. The accuracy of the measured value of the thermal conductivity of the object to be measured is increased.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

Embodiment 1 FIG.
1 is an overall configuration diagram showing a thermal conductivity measuring apparatus according to Embodiment 1 of the present invention. In the figure, the object to be measured 23 is sandwiched between two rods 21 and 22, and when viewed in the z-axis direction, the upper rod of the object to be measured 23 is the heating side rod 21, and the lower rod is the cooling side rod 22. To do. The heating side rod 21 and the cooling side rod 22 are provided with a plurality of holes in the z-axis direction, and each hole is composed of a thermocouple for measuring the z-axis direction temperature distribution in the rod. Rod temperature measuring sensors 41 and 42 are inserted. The measured object 23 is also provided with a plurality of holes in the z-axis direction, and the measured object is composed of a thermocouple for measuring the z-axis direction temperature distribution inside the measured object. A body temperature measurement sensor 43 is inserted.

  A heating block 11 in which the heater 10 is inserted is disposed on the opposite side of the surface of the heating side rod 21 that contacts the measured object 23. Further, on the opposite side of the surface of the cooling side rod 22 that contacts the object to be measured 23, the cooling block 12 in which the refrigerant flows is arranged. Although FIG. 1 shows the heater 10 inserted in the heating block 11, the heater 10 may have any configuration such as a ceramic heater. Moreover, although it demonstrated that the refrigerant | coolant was passing through the inside of the cooling block 12, you may use cooling devices, such as a heat sink and a Peltier device.

  An additional force device 15 for varying the contact surface pressure between the rods 21 and 22 and the measured object 23 is disposed on the heating block 11. In FIG. 1, a slide-type pressurization device that operates by a screw mechanism is shown as the additional force device 15, but a pressurization device having another configuration may be used. In addition, 15a is a rod of the additional force device 15, and 15b is a spring. A load cell 13 is installed for measuring the contact surface pressure that is changed by the applied force device 15. In this case, a heat insulating support member 14 is disposed between the heating block 11 and the load cell 13 so that the temperature of the load cell 13 does not reach the high temperature due to the heat transmitted from the heating block 11.

  A compensation heater 32 supported by a compensation heater flange 31 is disposed on the outer circumference of the heating side rod 21, the cooling side rod 22, and the object to be measured 23. FIG. 2 is an enlarged view showing the configuration of the heating side rod 21. The cooling side rod 22 and the measured object 23 are also configured in the same manner as in FIG.

  In FIG. 2, the compensation heater flange 31 is disposed so as to cover the entire outer periphery of the heating side rod 21 and is formed of a heat insulating member. In this example, a cylindrical heat insulating resin molded product covering the outer periphery of the heating side rod 21 is used as the compensation heater flange 31. A plurality of compensation heaters 32 (32a, 32b, 32c, 32d, 32e) are provided at predetermined intervals (preferably equal intervals) of the compensation heater flange 31 in the z-axis direction. In this case, the gap 34 between the compensation heater 32 and the heating side rod 21 is made as small as possible so that they do not contact each other.

  The compensation heater flange 31 is provided with a hole, and a compensation heater temperature measuring sensor comprising a thermocouple for measuring the temperature of each compensation heater 32 (32a, 32b, 32c, 32d, 32e) is provided in the hole. 33 (33a, 33b, 33c, 33d, 33e) is embedded. Each compensation heater temperature measurement sensor 33 (33a, 33b, 33c, 33d, 33e) is positioned at the same height in the z-axis direction as the rod temperature measurement sensor 41 (41a, 41b, 41c, 41d, 41e) described above. It is arranged.

  The compensation heater temperature detection unit 101 receives a signal from the compensation heater temperature measurement sensor 33 (33a, 33b, 33c, 33d, 33e), and determines the temperature of each compensation heater 32 (32a, 32b, 32c, 32d, 32e). Plays the role of calculating. The rod (measurement object) temperature detection unit 102 inputs signals from the rod temperature measurement sensors 41 (41a, 41b, 41c, 41d, 41e), 42 or the measurement object temperature measurement sensor 43, and the rods 21, 22 or It plays the role of calculating the temperature in the z-axis direction of the measured object 23. The compensation heater temperature control unit 103 includes the temperature of each compensation heater calculated by the compensation heater temperature detection unit 101 and the temperature in the z-axis direction of the rod or the measurement target calculated by the rod (measurement target) temperature detection unit 102. And the heating value of each compensation heater 32 (32a, 32b, 32c, 32d, 32e) is controlled so as to match.

  Further, as shown in FIG. 1, two displacement measurement plates 61a and 61b are provided so as to sandwich the measurement target 23 so that the thickness of the measurement target 23 can be measured, and the two displacement measurement plates 61a, A contact-type displacement meter 62 for measuring the distance between 61b is provided. The contact displacement meter 62 is supported by a displacement meter flange 63 so as to be positioned between the displacement measuring plates 61a and 61b.

Next, the operation of the thermal conductivity measuring apparatus according to Embodiment 1 of the present invention will be described. The amount of heat of the heating block 11 heated by the heater 10 is transmitted in the direction of lower temperature, that is, in the negative direction of the heating side rod 21, the measured object 23, the cooling side rod 22, and the cooling block 12 and the z axis. To go. By measuring the temperature gradients (∂T ₁ / ∂z) and (∂T ₂ / ∂z) of the two rods 21 and 22 sandwiching the measurement target 23, the measurement target represented by (Expression 1) The heat flux q flowing into and out of the body 23 can be measured. Then, the contact thermal resistance R _c or the thermal conductivity k _u of the measured object is obtained by the following (Formula 4) or (Formula 6) as described above.

  Next, temperature control of the compensation heater 32, which is a feature of the present embodiment, will be described based on the configuration diagram of the heating side rod 21 in FIG. The temperature of the compensation heater 32 (32a, 32b, 32c, 32d, 32e) is sequentially measured by the compensation heater temperature measurement sensor 33 (33a, 33b, 33c, 33d, 33e) and calculated by the compensation heater temperature detection unit 101. . On the other hand, the temperature of the rod 21 at the same position in the z-axis direction as the compensation heater temperature measurement sensor 33 (33a, 33b, 33c, 33d, 33e) is the rod temperature measurement sensor 41 (41a, 41b, 41c, 41d, 41e). Are sequentially measured and calculated by the rod (measurement object) temperature detection unit 102. The compensation heater temperature control unit 103 calculates the temperature of each compensation heater calculated by the compensation heater temperature detection unit 101 and the temperature in the z-axis direction of the rod calculated by the rod (measurement object) temperature detection unit 102. Energization control is performed on the compensation heater input line 36 so as to match, and the temperature of the compensation heater 32 (32a, 32b, 32c, 32d, 32e) is controlled.

As shown in FIG. 2, for example, five rod temperature measuring sensors 41 for measuring the temperature in the heating side rod 21 are provided, and the same height in the z-axis direction is compensated so as to correspond to the sensors 41. For example, five compensation heater temperature measurement sensors 33 for measuring the temperature of the heater 32 are also provided on the compensation heater flange 31. If the temperature of all of these compensation heaters 32 can be controlled to be equal to the temperature in the heating side rod 21 at the same height, the heat in the rod cross section with the z axis in the heating side rod 21 as the normal line. The movement is lost, the heat moves only in the z-axis direction, and the temperature gradient (∂T ₁ / ∂z) of the rod is also an ideal linear line.

Further, if the number of the compensation heaters 32 is arranged so as to be equal to or more than the total number of the temperature measuring sensors 41 of the heating side rod 21, the compensation heater 32 can be finely controlled. (∂T ₁ / ∂z) is also a more accurate primary line.

However, if heat transfer by natural convection exists between the compensation heater 32 and the rod 21, heat transfer occurs within the rod 21 within the rod cross section with the z axis as the normal. For this reason, the heat transmitted through the inside of the rod 21 by heat conduction is not only in the z-axis direction, the temperature in the same rod cross section with the z-axis as the normal is not uniform, and the temperature gradient (∂T ₁ / ∂z) is also It is no longer an ideal linear line. Therefore, in order to prevent heat transfer due to natural convection, the gap 34 between the rod 21 and the compensation heater 32 should be as small as possible. On the other hand, when the rod 21 and the compensation heater 32 are brought into contact with each other, heat transfer due to heat conduction may occur between the rod 21 and the compensation heater 32, and thus the contact should not be made. Therefore, it is desirable that the gap 34 be as small as possible so that the rod 21 and the compensation heater 32 are not brought into contact with each other.

  Further, in the arrangement of the compensation heaters 32 (32a, 32b, 32c, 32d, 32e), in order to avoid heat transfer due to a temperature difference between adjacent compensation heaters, the adjacent compensation heaters 32 are not in close contact with each other and a gap 35 is provided. Is preferable. Moreover, in order to avoid the heat transfer transmitted by heat conduction through the compensation heater flange 31, it is desirable that the compensation heater flange 31 is formed of a heat insulating member.

Although the above description is about the heating side rod 21, this can be similarly applied to the cooling side rod 22 and the measured object 23. In this way, since the temperature gradient in the Z-axis direction of the heating side rod 21, the cooling side rod 22, and the measured object 23 can be an ideal linear line, it is expressed by (Expression 4) and (Expression 6). It is possible to accurately measure the contact thermal resistance R _c and the thermal conductivity _ku of the object to be measured.

Moreover, when the to-be-measured body 23 becomes high temperature, the case where the thickness of itself changes may be considered. The change in the thickness of the measurement target 23 affects the temperature gradient (∂T ₃ / ∂z) of the measurement target 23. Therefore, if the thickness of the measured object 23 can be measured sequentially, there is an advantage that the temperature gradient (∂T ₃ / ∂z) of the measured object 23 can be corrected sequentially. Therefore, two displacement measurement plates 61a and 61b are arranged so as to sandwich the measurement target 23 so that the thickness of the measurement target 23 can be measured, and a contact-type displacement measurement meter is disposed between the displacement measurement plates 61a and 61b. 62 is installed. That is, by measuring the displacement of the two displacement measuring plates 61a and 61b positioned up and down by the contact-type displacement measuring instrument 62, the thickness of the measured object 23 is measured, and the temperature gradient (∂T ₃ / ∂z) is sequentially corrected.

As described above, according to the present embodiment, a plurality of compensation heaters 32 are arranged on the outer circumferences of the heating side rod 21, the cooling side rod 22, and the measured object 23, and the temperature of each compensation heater 32 and each compensation heater 32 are arranged. Since the heating value of the compensation heater 32 is controlled so that the temperature of the heating side rod 21, the cooling side rod 22 and the measured object 23 at the same height as the temperature measurement point 32 is equal, the heating side rod 21, the amount of heat leakage from the cooling side rod 22 and the measured object 23 in the peripheral direction can be reduced, and the amount of heat that flows in can be transmitted in a one-dimensional manner from the heating side rod 21 to the cooling rod 22 through the measured object 23. it can. As a result, it is possible to improve the accuracy of measurement of the thermal contact resistance R _c or thermal conductivity k _u of rod and object to be measured.

  Further, the number of the compensation heaters 32 is arranged so as to be equal to or more than the total temperature measurement points of the rod or the object to be measured, and each compensation heater 32 is independently controlled. The amount of heat leakage from the body to the surrounding direction can be suppressed, and heat can be transferred from the rod to the object to be measured in one dimension, so that the accuracy of the measured value of the thermal conductivity of the object to be measured can be increased. .

  Further, since the compensation heater 32 is fixed on the flange 31 that covers the outer periphery of the rod or the object to be measured and the adjacent compensation heaters 32 are not in contact with each other, the amount of heat transfer between the adjacent compensation heaters 32 is small. Since the flange 31 prevents heat leakage due to natural convection from the rod or the outer periphery of the measured object, the amount of heat input to the compensation heater 32 can be reduced.

  Further, the flange 31 is constituted by a heat insulating member that covers the outer periphery of the rod or the measured object leaving a gap, and the compensation heater is disposed on the rod side or measured object side on the heat insulating member. Therefore, the amount of heat generated from the compensation heater can be reduced. In addition, since the heat insulating member prevents heat leakage due to natural convection from the outer circumference of the rod or measured object, the amount of heat leakage from the rod or measured object to the surrounding direction can be suppressed, and heat is measured from the rod. Since it can be transmitted to the body in one dimension, the accuracy of the measured value of the thermal conductivity of the object to be measured is increased.

Embodiment 2. FIG.
FIG. 3 is an overall configuration diagram showing a thermal conductivity measuring apparatus according to Embodiment 2 of the present invention.

  In the first embodiment, the cooling block 12, the cooling side rod 22, the measured object 23, the heating side rod 21, and the heating block 11 are laminated in the positive direction from below the z axis. For this reason, heat insulation from the side of the heating block 11 that is in contact with the heating side rod 21 is insulated so that heat from the heating side block 11 flows in the negative direction of the z-axis and the temperature of the load cell 13 does not rise. It was necessary to interpose a support member 14 having a positive characteristic.

  In the second embodiment, as shown in FIG. 3, the heating block 11, the heating side rod 21, the measured object 23, the cooling side rod 22, and the cooling block 12 are stacked in the positive direction from below the z axis. The load cell 13 is arranged above the cooling block 12. According to this configuration, the distance between the load cell 13 and the heating block 11 increases and the thermal resistance also increases, so that heat does not flow toward the load cell 13 and the temperature of the load cell 13 does not rise. Therefore, the heat insulating support member 14 described in the first embodiment is not necessary, and the configuration of the thermal conductivity measuring device 1 is simplified.

  In the present embodiment, it goes without saying that the same compensation heater as that of the first embodiment is arranged on the outer periphery of the heating side rod 21, the cooling side rod 22 and the measured object 23.

Embodiment 3 FIG.
4 and 5 are configuration diagrams showing a rod of a thermal conductivity measuring device according to Embodiment 3 of the present invention. 4 and 5 show enlarged views of the heating side rod as a representative example, but the same applies to the cooling side rod and the object to be measured, and the same applies to the following description.

In the first embodiment, it has been stated that it is better to shrink as much as possible so that the gap 34 between the heating side rod 21 and the compensation heater 32 is not brought into contact. This is because if this gap 34 is large, natural convection occurs in the space 38 formed by the heating side rod 21 and the compensation heater 32 due to the temperature difference in the z-axis direction on the side surface of the heating side rod 21, and this natural convection heat. Due to the transmission, the temperature in the rod cross section with the z axis of the heating side rod 21 as the normal is not uniform, and heat transfer occurs. That is, since the heat transmitted through the heat conduction rod 21 by heat conduction is not only in the z-axis direction, the temperature gradient (∂T ₁ / ∂z) is not an ideal linear line.

  However, in practice, it is difficult to reduce the gap 34 as much as possible so as not to contact the gap 34. Therefore, in the present embodiment, as shown in FIG. 4, a gap support member 37 is provided so as to obtain an optimum gap 34. Similar to the compensation heater 32, the gap support member 37 is supported by the compensation heater flange 31. The tip of the gap support member 37 is in contact with the heating side rod 21 to support the heating side rod 21. Further, the gap support member 37 is formed of a heat insulating member so that heat from the heating side rod 21 is not transmitted to the gap support member 37. Further, since the space 38 formed by the compensation heater 32 and the heating side rod 21 is divided into small portions in the z-axis direction by the gap support member 37, the temperature difference between the maximum temperature and the minimum temperature in each divided space. Therefore, there is an advantage that the occurrence of natural convection heat transfer depending on the temperature difference can be suppressed.

  In addition, by setting the gap support member 37 to an appropriate length, the gap 34 can be easily set to an optimum value.

Therefore, the temperature in the rod cross section with the z axis in the heating side rod 21 as the normal is uniform, there is no heat transfer in this plane, and the heat moves only in the z axis direction. Therefore, as a result of the temperature gradient (∂T ₁ / ∂z) in the rod also becoming an ideal linear line, the contact thermal resistance R _c represented by the equations (4) and (6), the heat conduction of the measured object The rate k _u can be measured with high accuracy.

  In addition, since the gap support member 37 having heat insulation is disposed between the adjacent auxiliary heaters 32, heat conduction due to a temperature difference between the auxiliary heaters 32 can be prevented, and therefore the input amount to the compensation heater 32 is also small. The control of the compensation heater 32 is simplified.

  On the other hand, FIG. 5 shows a configuration in which a fin-like natural convection prevention plate 39 is installed in the gap 34 between the heating side rod 21 and the compensation heater 32. The natural convection prevention plate 39 has a fin 51 protruding from the compensation heater 32 side to the heating side rod 21 side, and the tip of the fin 51 contacts the heating side rod 21 to support the heating side rod 21. Further, the natural convection prevention plate 39 has a heat insulating property so that the heat from the heating side rod 21 is not transmitted to the natural convection prevention plate 39.

The fins 51 of the natural convection prevention plate 39 are also divided in order to divide the space 38 formed by the compensation heater 32 and the heating side rod 21 in the z-axis direction, similarly to the gap support member 37 in FIG. Since the temperature difference between the maximum temperature and the minimum temperature in each space is also reduced, the occurrence of natural convection heat transfer depending on the temperature difference can be suppressed. Therefore, there is no heat transfer in the rod cross section with the z axis in the heating side rod 21 as a normal line, and heat moves only in the z axis direction. As a result, since the temperature gradient (∂T ₁ / ∂z) in the rod also becomes an ideal linear line, the contact thermal resistance R _c represented by the equations (4) and (6) and the heat of the measured object The conductivity k _u can be measured with high accuracy.

  In the present embodiment, it goes without saying that the same compensation heater as that of the first embodiment is arranged on the outer periphery of the heating side rod 21, the cooling side rod 22 and the measured object 23.

Embodiment 4 FIG.
FIG. 6 is an overall configuration diagram showing a thermal conductivity measuring apparatus according to Embodiment 4 of the present invention. In the present embodiment, a compensation heating block 16 is provided between the cooling side rod 22 and the cooling block 12.

  When the thermal conductivity of the measured object 23 is temperature dependent, it is necessary to set the measured object 23 to an optimum temperature condition. In the first embodiment, the measured object 23 has a configuration in which it is sandwiched and stacked between the heating side rod 21 and the cooling side rod 22, and when the temperature of the measured object 23 is desired to be high, the temperature of the heating side rod 21. However, it is necessary to raise the temperature further, and workability deteriorates.

  Therefore, in the present embodiment, the compensation heating block 16 is provided between the cooling side rod 22 and the cooling block 12, and the temperature of the cooling side rod 22 is raised by raising the compensation heating block 16 to a predetermined temperature. Thereby, the temperature of the measured object 23 can be increased without increasing the amount of heat from the heating block 11 so much, and there is an advantage that workability is improved.

  As described above, according to the present embodiment, the heating amount Q1 is loaded from the side of the heating side rod 21 that does not contact the measured body 23, and the heating side Q2 generates heat from the side that does not contact the measured body 23 of the cooling side rod 22. Since the amount Q2 (Q1> Q2) is loaded, the rod 21 can be prevented from reaching a high temperature and the workability can be improved even when measuring the thermal conductivity having temperature dependency.

  In the present embodiment, it goes without saying that the same compensation heater as that of the first embodiment is arranged on the outer periphery of the heating side rod 21, the cooling side rod 22 and the measured object 23.

Embodiment 5. FIG.
FIG. 7 is an overall configuration diagram showing a thermal conductivity measuring device according to Embodiment 5 of the present invention.

  In the first embodiment, in order to measure the thickness of the measured object 23, the two displacement measuring plates 61a and 61b are arranged above and below the measured object 23, and the contact-type displacement measuring instrument 62 is arranged therebetween. It was. However, since the contact-type displacement meter 62 is in direct contact with the two displacement measuring plates 61a and 61b, there is a possibility that the thickness of the measured object 23 is affected.

  Therefore, the present embodiment is characterized in that the laser displacement meter 64 is used instead of the contact displacement meter 62. That is, the laser displacement meter 64 emits laser light 65 toward the two displacement measurement plates 61a and 61b, and the laser displacement meter 64 reflects the laser light 65 reflected by the two displacement measurement plates 61a and 61b. Receive. Then, by measuring the time difference of the received laser beam 65, the displacement of the two displacement measuring plates 61a and 61b, that is, the thickness of the measured object 23 is measured.

  As described above, according to the fifth embodiment, the distance between the two displacement measurement plates 61a and 61b can be measured in a non-contact manner, so that the thickness of the measured object 23 is not affected. The thickness of the measuring body 23 can be measured.

  In the present embodiment, it goes without saying that the same compensation heater as that of the first embodiment is arranged on the outer periphery of the heating side rod 21, the cooling side rod 22 and the measured object 23.

Embodiment 6 FIG.
In the above embodiment, the measurement object 23 is provided with a plurality of holes in the z-axis direction, and the measurement object is constituted by a thermocouple for measuring the temperature distribution in the z-axis direction inside the measurement object in the hole. The body temperature measuring sensor 43 is inserted. However, when there is almost no thickness in the z-axis direction of the measured object 23, or when a temperature sensor such as a thermocouple cannot be attached to the measured object 23, the z in the heating side rod 21 and the cooling side rod 22 is increased. Rod temperature measurement sensors 41 and 42 for measuring the axial temperature distribution are attached, and a plurality of compensation heaters 32 are arranged on the outer circumferences of the heating side rod 21 and the cooling side rod 22 to determine the temperature of the compensation heater 32 and the compensation heater. The amount of heat generated by the compensation heater 32 may be controlled so that the temperatures of the heating side rod 21 and the cooling side rod 22 at the same height as the temperature measurement point 32 are equal. In this case, when calculating the thermal conductivity k _u of the object to be measured 23, each of the temperature gradient [Delta] T (the two rods shown in the temperature gradient of the z-axis direction of the object to be measured 23 (Equation 4) (Temperature difference obtained from the extrapolation line) and substituting it into (Equation 6).

  As described above, according to the present embodiment, a plurality of compensation heaters 32 are arranged on the outer periphery of the heating side rod 21 and the cooling side rod 22, and the temperature of each compensation heater 32 and the temperature measurement point of each compensation heater 32. Since the amount of heat generated by the compensation heater 32 is controlled so that the temperatures of the heating side rod 21 and the cooling side rod 22 at the same height are equal to each other, from the heating side rod 21 and the cooling side rod 22 to the peripheral direction. The amount of heat flowing in can be transmitted in a one-dimensional manner from the heating side rod 21 to the cooling rod 22 through the measured object 23, so that the measured value of the thermal conductivity of the measured object 23 can be reduced. Increases accuracy.

It is a whole block diagram which shows the thermal conductivity measuring apparatus by Embodiment 1 of this invention. It is an enlarged view which shows the structure of the heating side rod of the thermal conductivity measuring apparatus of Embodiment 1 of this invention. It is a whole block diagram which shows the heat conductivity measuring apparatus by Embodiment 2 of this invention. It is a block diagram which shows the rod of the thermal conductivity measuring apparatus by Embodiment 3 of this invention. It is a block diagram which shows the rod of the thermal conductivity measuring apparatus by Embodiment 3 of this invention. It is a whole block diagram which shows the heat conductivity measuring apparatus by Embodiment 4 of this invention. It is a whole block diagram which shows the heat conductivity measuring apparatus by Embodiment 5 of this invention. It is a block diagram of the thermal conductivity measuring apparatus disclosed by the paper Themal Conductance of Multilayered Metalic Sheets. It is a figure which shows the temperature distribution of the rod and to-be-measured body of the thermal conductivity measuring apparatus of FIG.

Explanation of symbols

1 thermal conductivity measuring device, 10 heater, 11 heating block, 12 cooling block,
13 load cell, 14 support member, 15 additional force device, 21 heating side rod,
22 Cooling side rod, 23 DUT, 31 Compensation heater flange,
32 Compensation heater, 33 Compensation heater temperature measurement sensor,
41, 42 Rod temperature measuring sensor, 43 Measuring object temperature measuring sensor,
61a, 61b displacement measurement plate, 62 contact displacement measurement plate,
101 Compensation heater temperature detection unit, 102 Rod (measurement object) temperature detection unit,
103 Compensation heater temperature control part.

Claims (14)

A heating side rod and a cooling side rod sandwiching the measurement object are provided, and heat is supplied from a side of the heating side rod that does not contact the measurement object, and the heating side rod, the measurement object, and the cooling side Calculate the amount of heat input to the measured object by flowing the heat amount from the side of the cooling side rod that does not come into contact with the measured object through the rod, and measuring the temperature gradient in the rods. And a thermal conductivity measuring device for measuring a thermal conductivity of the measured object or a contact thermal resistance between the rod and the measured object from a temperature gradient of the measured object,
A plurality of compensation heaters are arranged on the outer circumference of the heating side rod, the cooling side rod, and the measured object, respectively, and the heating at the same height as the temperature of each compensation heater and the temperature measurement point of each compensation heater. The heat conductivity measuring device, wherein the heat generation amount of the compensation heater is controlled so that the temperature of the side rod, the cooling side rod, and the measured object is equal. A heating side rod and a cooling side rod sandwiching the measurement object are provided, and heat is supplied from a side of the heating side rod that does not contact the measurement object, and the heating side rod, the measurement object, and the cooling side Calculate the amount of heat input to the measured object by flowing the heat amount from the side of the cooling side rod that does not come into contact with the measured object through the rod, and measuring the temperature gradient in the rods. And a thermal conductivity measuring device for measuring the thermal conductivity of the measured object or the contact thermal resistance between the rod and the measured object from the temperature gradient of the measured object, the heating side rod and the A plurality of compensation heaters are arranged on the outer periphery of the cooling side rod,
The amount of heat generated by the compensation heater is controlled so that the temperature of each compensation heater is equal to the temperature of the heating side rod and the cooling side rod at the same height as the temperature measurement point of each compensation heater. A thermal conductivity measuring device characterized by comprising: The number of installed compensation heaters is arranged so as to be equal to or more than the total temperature measurement points of the rod or the object to be measured, and each of the compensation heaters is independently controlled. The thermal conductivity measuring device according to claim 1 or 2. The compensation heater is fixed on a flange that covers the outer periphery of the rod or the measured object leaving a gap, and the adjacent compensation heaters are not in contact with each other. The thermal conductivity measuring device according to claim 2. The flange is constituted by a heat insulating member that covers the outer periphery of the rod or the measured object leaving a gap, and the compensation heater is disposed on the rod side or the measured object side on the heat insulating member. The thermal conductivity measuring device according to claim 4, wherein The thermal conductivity measuring device according to claim 4 or 5, wherein a clearance supporting member that contacts the outer peripheral surface of the rod or the object to be measured is disposed on the flange. 5. A natural convection prevention plate having fins in contact with the outer peripheral surface of the rod or the measured object is disposed in a gap between the flange and the outer periphery of the rod or the measured object. Or the thermal conductivity measuring apparatus of Claim 5. 2. An additional force device for varying a contact surface pressure between the rod and the object to be measured and a pressure sensor for measuring the contact surface pressure are provided. Item 3. The thermal conductivity measuring device according to Item 2. The thermal conductivity measuring device according to claim 8, wherein the pressure sensor is disposed on the cooling side rod side. 3. The temperature of the measurement object is controlled by applying a heat amount from a side of the measurement object that does not contact the cooling rod by a compensation heating block. Thermal conductivity measuring device. The thermal conductivity measuring device according to claim 1, further comprising a displacement measuring instrument for measuring the thickness of the object to be measured. The thermal conductivity measuring apparatus according to claim 9, wherein the displacement measuring instrument is a non-contact type displacement measuring instrument. Sandwiching the object to be measured between the heating side rod and the cooling side rod;
Control the temperature of the outer circumference of the heating side rod, the cooling side rod and the object to be measured to be equal to the temperature of the heating side rod, the cooling side rod and the object to be measured located at the same height. And a step of allowing heat to flow in from the side of the heating side rod that does not contact the object to be measured, and contacting the object to be measured of the cooling side rod through the heating side rod, the object to be measured, and the cooling side rod. The amount of heat is allowed to flow out from the non-conducting side, and the amount of heat input to the measured body is calculated by measuring the temperature gradient in the rods, and the measured amount of the measured body is calculated from the calculated amount of heat and the temperature gradient of the measured body. A method for measuring thermal conductivity, comprising a step of measuring thermal conductivity or contact thermal resistance between the rod and the object to be measured. Sandwiching the object to be measured between the heating side rod and the cooling side rod;
Controlling the temperature of the outer circumference of the heating side rod and the cooling side rod to be equal to the temperature of the heating side rod and the cooling side rod itself located at the same height;
The amount of heat is introduced from the side of the heating side rod that does not come into contact with the object to be measured, and passes through the heating side rod, the object to be measured, and the cooling side rod, and from the side of the cooling side rod that does not contact the object to be measured. The amount of heat is flowed out and the amount of heat input to the object to be measured is calculated by measuring the temperature gradient in both the rods. From the calculated amount of heat and the temperature gradient of the object to be measured, the thermal conductivity of the object to be measured or And a step of measuring a contact thermal resistance between the rod and the object to be measured.

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