JPH05119003A - Method for measuring temperature conductivity - Google Patents
Method for measuring temperature conductivityInfo
- Publication number
- JPH05119003A JPH05119003A JP3304034A JP30403491A JPH05119003A JP H05119003 A JPH05119003 A JP H05119003A JP 3304034 A JP3304034 A JP 3304034A JP 30403491 A JP30403491 A JP 30403491A JP H05119003 A JPH05119003 A JP H05119003A
- Authority
- JP
- Japan
- Prior art keywords
- temperature
- substance
- temperature difference
- thermal conductivity
- measuring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims description 39
- 238000010438 heat treatment Methods 0.000 claims abstract description 87
- 239000000126 substance Substances 0.000 claims abstract description 66
- 230000000704 physical effect Effects 0.000 claims description 26
- 238000011088 calibration curve Methods 0.000 claims description 19
- 230000020169 heat generation Effects 0.000 claims description 8
- 238000005259 measurement Methods 0.000 abstract description 35
- 238000001816 cooling Methods 0.000 abstract description 15
- 239000000498 cooling water Substances 0.000 abstract description 4
- 230000000977 initiatory effect Effects 0.000 abstract 2
- 230000008859 change Effects 0.000 description 30
- 239000000463 material Substances 0.000 description 26
- 239000012530 fluid Substances 0.000 description 20
- 238000012546 transfer Methods 0.000 description 11
- 239000000203 mixture Substances 0.000 description 10
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 8
- 239000008157 edible vegetable oil Substances 0.000 description 8
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 7
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 6
- 239000006185 dispersion Substances 0.000 description 6
- 239000008280 blood Substances 0.000 description 5
- 210000004369 blood Anatomy 0.000 description 5
- 238000002474 experimental method Methods 0.000 description 5
- 239000003921 oil Substances 0.000 description 5
- 235000013305 food Nutrition 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- 229920001817 Agar Polymers 0.000 description 3
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 3
- 239000008272 agar Substances 0.000 description 3
- 230000015271 coagulation Effects 0.000 description 3
- 238000005345 coagulation Methods 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 238000009792 diffusion process Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 239000000701 coagulant Substances 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000004806 packaging method and process Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 230000000638 stimulation Effects 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 108010010803 Gelatin Proteins 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 240000008415 Lactuca sativa Species 0.000 description 1
- 108010094028 Prothrombin Proteins 0.000 description 1
- 102100027378 Prothrombin Human genes 0.000 description 1
- 108090000190 Thrombin Proteins 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000004925 denaturation Methods 0.000 description 1
- 230000036425 denaturation Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000855 fermentation Methods 0.000 description 1
- 230000004151 fermentation Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 235000013611 frozen food Nutrition 0.000 description 1
- 239000000499 gel Substances 0.000 description 1
- 239000008273 gelatin Substances 0.000 description 1
- 229920000159 gelatin Polymers 0.000 description 1
- 235000019322 gelatine Nutrition 0.000 description 1
- 235000011852 gelatine desserts Nutrition 0.000 description 1
- 239000010438 granite Substances 0.000 description 1
- 235000015243 ice cream Nutrition 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 239000008267 milk Substances 0.000 description 1
- 210000004080 milk Anatomy 0.000 description 1
- 235000013336 milk Nutrition 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000005022 packaging material Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000006072 paste Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 229940039716 prothrombin Drugs 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 235000012045 salad Nutrition 0.000 description 1
- 230000001932 seasonal effect Effects 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 239000013076 target substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000010257 thawing Methods 0.000 description 1
- 229960004072 thrombin Drugs 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Measuring Temperature Or Quantity Of Heat (AREA)
- Investigating Or Analyzing Materials Using Thermal Means (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、物質と熱的に接触する
発熱体が発熱するとき該発熱体から各々異なる距離にあ
る測温素子もしくは該発熱体温度と該発熱体から一定距
離にある測温素子の温度の差が発熱開始から変化し、そ
の差が一定時間経過後は一定の幅を示すような物質にお
ける物質の物性値である温度伝導率を測定する方法に関
し、該温度伝導率の計測により被測定物質の材質特性を
知り、食品や工業製品の冷却、加熱における形状や条
件、及び包装形態、包装材質の設定や、冷却、加熱装置
の設計などに利用されるものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature measuring element located at a different distance from the heating element when the heating element in thermal contact with a substance generates heat or a temperature of the heating element and a fixed distance from the heating element. A method for measuring the thermal conductivity, which is the physical property value of a substance in which the difference in temperature of the temperature measuring element changes from the start of heat generation, and the difference shows a constant width after a certain period of time, By measuring the material properties of the substance to be measured by measuring, the shape and conditions of cooling and heating of foods and industrial products, the packaging form and packaging material, and the design of cooling and heating devices are used.
【０００２】[0002]
【従来の技術】従来、非定常細線法により流体の熱伝導
率を計測する手段として、 「流体の熱伝導率の高精度測定に関する研究」長坂雄
次、長島昭、日本機械学論文集４７巻４１７号（昭５６
−５）８２１−８２９頁 「流体の熱伝導率の高精度測定に関する研究」長坂雄
次、長島昭、日本機械学論文集４７巻４１９号（昭５６
−７）１３２３−１３３１頁がある。これらの文献によ
ると非定常細線法により流体の熱伝導率、温度伝導率が
計測可能であり、更に実験による追試確認も可能である
ことが記載されている。これらの方法は、流体と熱的に
接触する素子の発熱開始からの温度変化を計測し、その
温度が対数時間軸に対して直線的に変化する非定常状態
における温度勾配を計測する手段である。ここで、熱伝
導率は物質の物性を現す値の一つであり、物質の熱伝導
率を知ることは物質の熱の性質の一つを把握可能とし、
身近には耐火材の設計や、食品の熱変性の把握などに役
立てられている。また、細線を利用した流体の物性の測
定法として、本出願人が先に開示した 特開昭５９−２１７１６２号「乳凝固の測定方法」の
ように、流体の粘性変化を判定するために細線の温度変
化を指標としたものがある。この発明は流体の粘性とい
う物性を実測値として計測するものではなく、粘性とい
う物性が変化することを細線の定常状態における温度変
化から把握するものである。更に、このような粘性変化
と細線温度の定常状態における変化を利用するものとし
て、本出願人が先に開示した 特開昭６０−１５２９４３号「液体及び半固体状物質
の物性変化の測定方法」がある。この発明は、非定常状
態において熱伝導率の測定が可能な方法を利用すること
によって、流体の物性の一つである動粘性率の変化を計
測することが可能であることを主体としている。即ち、
動粘性率は流体の粘度を密度で割った値であるが、熱伝
達率が熱伝導率と関係しており、動粘性率の変化が熱伝
達率を介して熱伝導率の変化により把握可能であるとい
う理論に基づくものである。なお、この発明は動粘性率
を実測値として求めるものではなく、その変化の有無を
把握しようとするものである。更に、本出願人が先に開
示した 特開平１−２２７０６２号「血液等の粘性変化の測定
方法」は、流体である血液が刺激されてから凝固するま
での医学的に重要な時間であるプロトロンビン時間やト
ロンビン時間の計測に細線技術を応用した発明である。
この発明により、血液の刺激から凝固までの時間を血液
の粘性変化から高精度に計測できることを明かにしてい
る。また、この発明は流体（血液）の物性変化である粘
性変化を細線の定常状態における温度変化や該温度変化
から把握可能な他の物性変化から把握して時間計測する
ことを主体としており、このことからも流体の物性を知
ることの重要性が理解される。なお、従来の測温素子の
機能を有する発熱体を内蔵するセンサーに関して、例え
ば特開昭６４−４４８３８号のような具体例がある。流
体の細線加熱法による従来技術では、以上のように非定
常状態における温度変化から物性の一部である熱伝導率
を実測値として得られること、また、定常状態の温度変
化から物性である粘性の変化の有無を知ることが可能で
あることが明らかになっている。その他、 「熱計測技術」荒木伸幸（日本機械学会編、朝倉書店
発行、１０７頁）には熱的接触を利用した温度伝導率を
計測する方法が記載されており、また、 「レーザーパルス法による熱常数の測定」難波進他二
名（応用物理、第３６巻、第８号、１９６７、６６１〜
６６５頁）にはレーザーパルスによる熱拡散率の測定に
ついて検討されている。この資料では、瞬間熱源が照射
されてから試料の反対面における温度が最大値の１／２
に達するまでに要する時間と熱拡散率の関係について報
告されている。2. Description of the Related Art Conventionally, as a means for measuring the thermal conductivity of a fluid by the unsteady thin wire method, "Research on high-precision measurement of thermal conductivity of fluid" Yuji Nagasaka, Akira Nagashima, Vol. Issue (Sho 56
-5) pp. 821-829 "Study on high precision measurement of thermal conductivity of fluids" Yuji Nagasaka, Akira Nagashima, Vol.
-7) There are pages 1323-1331. According to these documents, it is described that the thermal conductivity and the thermal conductivity of the fluid can be measured by the unsteady thin wire method, and the additional test can be confirmed by experiments. These methods are means for measuring a temperature change from the start of heat generation of an element that is in thermal contact with a fluid and measuring a temperature gradient in an unsteady state in which the temperature changes linearly with respect to a logarithmic time axis. .. Here, the thermal conductivity is one of the values that express the physical properties of a substance, and knowing the thermal conductivity of a substance makes it possible to grasp one of the heat properties of the substance,
It is useful for designing refractory materials and understanding the thermal denaturation of foods. Further, as a method for measuring physical properties of a fluid using a thin wire, a thin wire for determining a viscosity change of the fluid is disclosed in Japanese Patent Laid-Open No. 59-217162 “Measurement method for milk coagulation” previously disclosed by the present applicant. There is one that uses the temperature change of as an index. This invention does not measure the physical property of the fluid viscosity as an actual measurement value, but grasps the change of the physical property of viscosity from the temperature change in the steady state of the thin line. Furthermore, in order to utilize such a change in viscosity and a change in thin wire temperature in a steady state, Japanese Patent Application Laid-Open No. 60-152943 “Method for measuring change in physical properties of liquid and semi-solid substances” disclosed by the present applicant. There is. The present invention is mainly based on the fact that it is possible to measure a change in the kinematic viscosity, which is one of the physical properties of a fluid, by using a method capable of measuring the thermal conductivity in an unsteady state. That is,
The kinematic viscosity is the value obtained by dividing the viscosity of the fluid by the density, but the heat transfer coefficient is related to the heat conductivity, and the change in the kinematic viscosity can be grasped by the change in the heat conductivity via the heat transfer coefficient. It is based on the theory that It should be noted that the present invention does not seek the kinematic viscosity as a measured value, but tries to grasp the presence or absence of a change. Furthermore, Japanese Patent Application Laid-Open No. 1-227062 “Method of measuring viscosity change of blood etc.” disclosed by the present applicant is prothrombin which is a medically important time from stimulation of blood which is a fluid to coagulation. It is an invention that applies the thin wire technique to the measurement of time and thrombin time.
According to the present invention, it is made clear that the time from blood stimulation to coagulation can be measured with high accuracy from blood viscosity change. Further, the present invention is mainly based on grasping a viscosity change, which is a physical property change of a fluid (blood), from a temperature change in a steady state of a thin wire and other physical property changes which can be grasped from the temperature change, and measuring the time. From this, it is understood that it is important to know the physical properties of the fluid. Incidentally, regarding a sensor having a built-in heating element having a function of a conventional temperature measuring element, there is a specific example as disclosed in JP-A-64-44838. In the conventional technology using the thin wire heating method for fluids, the thermal conductivity, which is a part of the physical properties, can be obtained as an actual measurement value from the temperature change in the unsteady state as described above, and the viscosity that is the physical property can be obtained from the temperature change in the steady state. It has become clear that it is possible to know whether or not the change has occurred. In addition, "Thermal measurement technology" Nobuyuki Araki (edited by The Japan Society of Mechanical Engineers, published by Asakura Shoten, p. 107) describes a method for measuring thermal conductivity using thermal contact. "Measurement of heat constant" Susumu Namba and 2 others (Applied Physics, Volume 36, No. 8, 1967, 661-)
(Pp. 665) discusses the measurement of thermal diffusivity by laser pulses. In this document, the temperature on the opposite surface of the sample after irradiation with the instantaneous heat source is 1/2 of the maximum value.
The relationship between the time required to reach the temperature and the thermal diffusivity is reported.
【０００３】[0003]
【発明が解決しようとする課題】例えば特公平２−３１
９３２号に示されるように、従来の細線加熱法において
もその指標値の変化から流体の粘性変化の状態を把握す
ることが行われている。しかし、各種産業分野において
流体の状態変化を計測する場合には、粘性変化の状態を
把握すれば良いというだけにとどまらず、実質的な物性
値を求め、その物性値に基づいて工程を制御することが
必要とされる場合もある。そのような場合は動粘性率、
粘性値、熱伝導率、温度伝導率などの物性値を時間をか
けて数値として計測するようにしている。また、液体や
気体に限らず、固体状、ペースト状、スラリー状などの
物質においても物性値を数値として計測することが要求
されている。例えば、アイスクリームの冷却、発酵後の
パン焼き、冷凍食品の解凍・凍結等の熱伝導現象に支配
される工程にあってはその現象を充分に知悉し、製品の
形状や大きさを決定したり装置の性能、形式等を設計す
るからである。そして、以上のような熱伝導現象におい
て温度伝導率は熱移動を支配する重要な物性値であり、
これを正確に計測することは産業上重要な手段である。
また、物質の温度伝導率は比熱と密度に関係しているこ
とから、物質の構成内容や物質自体の環境温度によって
変化し、これを簡単に計測することが望まれる。ここ
で、上記従来技術として揚げた、には非定常細線加
熱法により温度伝導率ａが計測可能である旨の記載があ
るものの、被測定物の密度ρ、比熱Ｃｐが既知であるこ
とを前提としており、その方法によって求めた熱伝導率
λから、 ａ ＝ λ ／ Ｃｐ・ρ により温度伝導率ａを求める方法である。従って、前提
として被測定物の密度ρ、比熱Ｃｐの両方が既知である
ことを要するが、実際の工業工程ではこれらの値が既知
であることは希であり、例えば食品などにあっては混合
物が多く、また、季節や環境の変動によって成分配分に
変更があり、現実問題として被測定物の密度ρや比熱Ｃ
ｐを知ることは不可能である。特に固体物質では理論的
には発熱体の発熱による熱伝導が従来の細線加熱法でい
うところの定常状態を示さず、永久的に非定常であるた
め、従来の細線加熱法によっては温度伝導率を熱伝導率
の介在無しで得ることは不可能である。また、上記〜
によって流体の物性値を実測値として得ることは困難
である。即ち、これらの計測においては粘性率を実質値
として知る必要はなく、変化の始点や終点を時期的に把
握する方法である。これらの発明では、物性の一つであ
る粘性変化に基づく流体の状態把握であって物性の他の
一つである温度伝導率の把握がどのような流体の状態を
把握することになるかが明らかにされていない。更に、
はレーザーパルス法により一方面から多方面に達する
温度の最大値の半分に達するまでの時間と熱拡散率（温
度伝導率）の関係であり、固体試料以外には特殊な容器
を要し、先に述べたペースト状、スラリー状の試料では
特に均質性が問題となって、測定に時間を要すると共に
インライン計測は不可能である。また、この測定におい
ては熱伝導の定常、非定常は問題ではなく、試料の厚み
が計測の主たる要因となっている。しかし、この試料で
重要なことは、熱の伝導中である温度の変化する時点で
は、熱伝導率が関係することなく熱拡散率を得ているこ
とであり、後に本発明でいう非定常域における熱伝導で
は温度伝導率のみが支配し、熱伝導率は無関係であるこ
とを示唆するものである。[Problems to be Solved by the Invention]
As shown in No. 932, even in the conventional thin wire heating method, the state of fluid viscosity change is grasped from the change of the index value. However, when measuring the state change of a fluid in various industrial fields, it is not only necessary to grasp the state of the viscosity change, but also to obtain substantial physical property values and control the process based on the physical property values. May be required. In such cases, the kinematic viscosity,
Physical properties such as viscosity, thermal conductivity, and thermal conductivity are measured numerically over time. Further, it is required to measure the physical property value as a numerical value not only in liquid or gas but also in substances such as solid, paste and slurry. For example, in processes that are governed by heat conduction phenomena such as cooling ice cream, baking after fermentation, thawing and freezing frozen foods, etc., we are fully aware of such phenomena and decide the shape and size of the product. This is because the performance and format of the device are designed. And, in the heat conduction phenomenon as described above, the thermal conductivity is an important physical property value that governs heat transfer,
Accurately measuring this is an important industrial tool.
Further, since the thermal conductivity of a substance is related to the specific heat and the density, it changes depending on the constituent content of the substance and the environmental temperature of the substance itself, and it is desired to easily measure this. Here, although there is a description that the temperature conductivity a can be measured by the unsteady thin wire heating method described in the above-mentioned prior art, it is premised that the density ρ and the specific heat Cp of the measured object are known. In this method, the thermal conductivity a is calculated from the thermal conductivity λ obtained by the method as follows: a = λ / Cp · ρ. Therefore, as a premise, it is necessary that both the density ρ and the specific heat Cp of the object to be measured be known, but it is rare that these values are known in the actual industrial process. However, there are many changes in the component distribution due to seasonal and environmental changes.
It is impossible to know p. In particular, in the case of solid substances, theoretically, the heat conduction due to the heat generated by the heating element does not show the steady state as in the conventional thin wire heating method and is permanently unsteady. Is not possible without the intervention of thermal conductivity. Also, above
Therefore, it is difficult to obtain the physical property value of the fluid as the actual measurement value. That is, in these measurements, it is not necessary to know the viscosity coefficient as a real value, and it is a method of grasping the start point and the end point of the change with time. In these inventions, the state of a fluid is grasped based on a change in viscosity, which is one of the physical properties, and what state of the fluid is grasped by grasping temperature conductivity which is another one of the physical properties. Not revealed. Furthermore,
Is the relationship between the time it takes for the laser pulse method to reach half of the maximum temperature that reaches one side to the other side and the thermal diffusivity (thermal conductivity), and requires a special container other than the solid sample. In the case of the paste-like and slurry-like samples described above, homogeneity becomes a problem, which requires a long time for measurement and in-line measurement is impossible. In this measurement, steady and non-steady state of heat conduction does not matter, and the thickness of the sample is the main factor of measurement. However, what is important in this sample is that the thermal diffusivity is obtained without any relation to the thermal conductivity at the time when the temperature changes during the conduction of heat. It is suggested that the thermal conductivity in the is governed only by the thermal conductivity, and that the thermal conductivity is irrelevant.
【０００４】[0004]
【課題を解決するための手段】従って、本発明は物質の
温度伝導率を実質的数値として簡単に計測できる方法を
提供することを目的とする。かかる目的を達成すべく、
発熱体から異なる距離にある少なくとも二つの測温素
子、もしくは自ら発熱し、かつ自らの温度を検出可能な
発熱体内蔵もしくは兼用の素子と測温素子を物質内に配
置し、発熱体を発熱せしめてそれら測温素子、もしくは
発熱体と測温素子の温度差が一定温度差を保つようにな
ったときの該温度差を求め、それら測温素子、もしくは
発熱体と測温素子の温度差が発熱開始から上記一定温度
差の１／Ｎの値に到達するまでの時間から物質の温度伝
導率を得ることを特徴とする温度伝導率の計測方法を発
明した。なお、これら二つの測温素子の距離は、物質内
の特定点からの距離をＬ１、Ｌ２としかつＬ１＜Ｌ２の
とき、Ｌ２／Ｌ１＞１となるように構成することが当然
であり、上記Ｎは１より大きい値として、計測される時
間が非定常域にあるように設定される。更に、以上のよ
うな方法により、二種以上の物性既知の物質を用いて各
物質の温度差の１／Ｎの温度差に到達する時間を計測し
て各物質の既知である温度伝導率から較正曲線を定め、
この較正曲線に基づいて温度伝導率が未知の物質の温度
伝導率を求めるようにした。SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for easily measuring the thermal conductivity of a substance as a substantially numerical value. To achieve this purpose,
At least two temperature measuring elements located at different distances from the heating element, or an element with a built-in or dual-purpose heating element that can generate its own temperature and detect its own temperature, and a temperature measuring element are placed in the substance to heat the heating element. Then, the temperature difference between the temperature measuring element or the heating element and the temperature measuring element is calculated when the temperature difference between the heating element and the temperature measuring element becomes constant, and the temperature difference between the temperature measuring element or the heating element and the temperature measuring element is calculated. A temperature conductivity measuring method is invented, wherein the temperature conductivity of a substance is obtained from the time from the start of heat generation until the value reaches 1 / N of the constant temperature difference. It should be noted that the distance between these two temperature measuring elements should be L2 / L1> 1 when L1 and L2 are distances from a specific point in the substance and L1 <L2. N is set to a value larger than 1 so that the measured time is in the unsteady region. Furthermore, by using the above method, the time required to reach a temperature difference of 1 / N of the temperature difference of each substance is measured using two or more types of substances whose physical properties are known, and the known temperature conductivity of each substance is calculated. Define a calibration curve,
Based on this calibration curve, the thermal conductivity of a substance whose thermal conductivity is unknown is determined.
【０００５】[0005]
【作用】物質内において発熱体と該発熱体から異なる距
離にある少なくとも二つの測温素子、もしくは自ら発熱
し、かつ自らの温度を検出可能な発熱体と測温素子を配
置し、発熱体を発熱させながら経時的に測温素子の温度
差、もしくは発熱体と測温素子の温度差を計測するとあ
る時間で一定の温度差を保つ準定常域に到達する。そし
て、このような準定常域に到達する前の非定常域の間に
おいて、これら測温素子の温度差、もしくは発熱体と測
温素子の温度差が上記準定常域の時の温度差の１／Ｎの
値に到達するまでの時間は温度伝導率に依存して変化す
る。本発明は、以上の性質を利用し、それら測温素子、
もしくは発熱体と測温素子の温度差が発熱開始から上記
一定温度差の１／Ｎの値に到達するまでの時間を計測す
ることにより物質の温度伝導率を得ようとするものであ
る。そして、以上のような方法において、二種以上の物
性既知の物質を用いて１／Ｎの温度差に到達する時間と
温度伝導率の較正曲線を定め、その較正曲線に基づいて
未知物質の温度伝導率を得るものである。なお、非定常
域において測定を行うためにＮは１より大きい値である
ことが条件となる。例えばＮ＝２等とすると計算が容易
である。また、このように非定常域において測定を行う
のは、定常域での熱伝導は熱伝達率が影響するからであ
り、熱伝導が温度伝導率に支配される非定常域において
測定を行う必要があるからである。ここで、温度伝導率
ａは比熱Ｃｐ、密度ρ、熱伝導率λの関数であり、一般
には次式 ａ ＝ ｆ（Ｃｐ、ρ、λ） で表されるが、非定常域においては熱伝導率λが関与し
ない関数となる。このことは先に従来技術のとしてあ
げた文献や伝熱工学資料：日本機械学会、改訂第４版、
昭和６１年１０月２０日出版、第１〜１４頁において明
らかにされている。即ち、これらの資料より、円筒座標
系の熱伝導方程式は、次式 ∂Ｔ／∂ｔ ＝ ａ（∂2 Ｔ／∂ｒ2 ＋ １／ｒ・∂Ｔ／∂ｔ） …（１） Ｔ：温度 ｔ：時間 ｒ：半径方向の距離 で表される。温度分布が時間によって変化が認められな
い定常熱伝導の状態では∂Ｔ／∂ｔ ＝ ０であり、そ
の時の基礎方程式は ∇2 Ｔ ＝ ０ が成り立つ。ここで、内部発熱がある場合は ∇2 Ｔ ＋ Ｑ’／λ ＝ ０ Ｑ’：発熱量 と表されるため、定常域では熱伝導率が関与してくる。
しかし、非定常域では ∂Ｔ／∂ｔ ≠ ０ であり、（１）式より温度伝導率ａのみに支配されるこ
とが分かる。なお、本発明でいう定常域、非定常域と
は、従来技術でいう定常状態、非定常状態とは意味が異
なる点に留意を要する。即ち、従来技術、等におい
て、流体中に配置した発熱体を発熱させて熱伝達を生じ
させたとき、発熱体の温度は対流熱伝達の安定域までは
上昇し続けるが、熱伝達が安定した後は一定温度とな
る。従来技術における定常状態とはこのように発熱体の
温度が一定となった状態であり、非定常状態とは発熱体
の温度がこのように一定となるまでの間の状態である。
一方、本発明のように物質内に位置する発熱体を発熱し
続けると、ある時間を経過した後は、発熱体からそれぞ
れ異なる距離にある二つの点の温度は一定の差を保った
まま上昇し続けるようになる。本発明でいう定常域と
は、このように二つの点の温度が一定の差を保ったまま
上昇し続けるようになった状態をいい、その一様温度差
の時間変化だけを扱う、いわゆる準定常域を指してい
る。非定常域とは二つの点の温度がこのように一定の差
を保つようになるまでの間の状態をいう。なお、理論的
には物質が無限の大きさを持っていると考えることがで
きるが、そのような場合には温度が永久的に上昇し続け
るので、 ∂Ｔ／∂ｔ ＝ ０ とならず、定常熱伝導でいう定常域は存在しないことと
なる。そこで準定常域という言葉を使用する。また、現
実には物質が有限の大きさをもっているため、本発明で
いう定常域（準定常域）における２点間の温度差が一定
である状態は永久ではなく、物質内の熱の蓄積により２
点間の温度は次第に接近するようになる。本発明では、
このような場合は熱伝導が異常になったものと見なし、
測定の対象としない。従って本発明は、準定常域に達し
てから非定常域に遡って２点間の温度差を測定して温度
伝導率を得ようとするものであり、上述したように非定
常域においては熱伝達率が温度伝導率に影響しない性質
を利用する手段である。[Function] The heating element and at least two temperature measuring elements located at different distances from the heating element in the substance, or the heating element and the temperature measuring element capable of detecting the temperature of itself and arranging the temperature of the heating element are arranged. When the temperature difference between the temperature measuring element or the temperature difference between the heating element and the temperature measuring element is measured over time while heat is generated, the temperature reaches a quasi-steady region where a constant temperature difference is maintained for a certain period of time. Then, in the non-steady region before reaching such a quasi-steady region, the temperature difference between these temperature measuring elements or the temperature difference between the heating element and the temperature measuring device is 1 of the temperature difference in the above quasi-steady region. The time required to reach the value of / N changes depending on the thermal conductivity. The present invention utilizes the above properties,
Alternatively, the temperature conductivity of the substance is obtained by measuring the time from the start of heat generation until the temperature difference between the heating element and the temperature measuring element reaches the value of 1 / N of the constant temperature difference. Then, in the method as described above, a calibration curve for the time to reach the temperature difference of 1 / N and the thermal conductivity is determined using two or more kinds of substances with known physical properties, and the temperature of the unknown substance is determined based on the calibration curve. It is to obtain conductivity. It should be noted that N is a value larger than 1 in order to perform the measurement in the non-stationary region. For example, if N = 2, the calculation is easy. In addition, the reason why the measurement is performed in the non-steady region is that the heat transfer in the steady region is affected by the heat transfer coefficient. Therefore, it is necessary to perform the measurement in the non-steady region where the heat transfer is governed by the thermal conductivity. Because there is. Here, the thermal conductivity a is a function of the specific heat Cp, the density ρ, and the thermal conductivity λ, and is generally expressed by the following equation a = f (Cp, ρ, λ), but the thermal conductivity in the non-steady region is The function is not related to the rate λ. This is based on the literature and heat transfer materials mentioned above as prior art: Japan Society of Mechanical Engineers, 4th revised edition,
Published on October 20, 1986, pages 1-14. That is, from these materials, the heat transfer equation of the cylindrical coordinate system is as follows: ∂T / ∂t = a (∂ 2 T / ∂r 2 + 1 / r∂T / ∂t) (1) T: Temperature t: time r: distance in radial direction In the state of steady heat conduction where the temperature distribution does not change with time, ∂T / ∂t = 0, and the basic equation at that time is ∇ 2 T = 0. Here, when internal heat is generated, it is expressed as ∇ 2 T + Q '/ λ = 0 Q': calorific value, so that the thermal conductivity is involved in the steady region.
However, in the non-stationary region, ∂T / ∂t ≠ 0, and it can be seen from the equation (1) that the thermal conductivity a is dominant. It should be noted that the steady region and the non-steady region in the present invention have different meanings from the steady state and the non-steady state in the conventional technique. That is, in the prior art, when the heat generating element arranged in the fluid is heated to generate heat transfer, the temperature of the heat generating element continues to rise up to the stable region of convective heat transfer, but the heat transfer becomes stable. After that, the temperature becomes constant. In the related art, the steady state is a state in which the temperature of the heating element is thus constant, and the unsteady state is a state until the temperature of the heating element is in such a constant state.
On the other hand, if the heating element located in the substance is continuously heated as in the present invention, the temperature at two points at different distances from the heating element rises while maintaining a constant difference after a certain time elapses. Will continue to do. The steady-state region in the present invention refers to a state in which the temperature at the two points continues to rise while maintaining a constant difference in this way, and handles only the time change of the uniform temperature difference, the so-called quasi-state. It refers to the stationary region. The non-stationary region is a state until the temperatures at the two points maintain such a constant difference. In theory, it can be considered that a substance has an infinite size, but in such a case, the temperature continues to rise permanently, so ∂T / ∂t = 0 does not hold, This means that there is no steady region for steady heat conduction. Therefore, the term quasi-stationary region is used. Further, in reality, since the substance has a finite size, the state in which the temperature difference between the two points in the steady region (quasi-steady region) according to the present invention is not constant is not permanent, but is due to the accumulation of heat in the substance. Two
The temperature between the points gradually approaches. In the present invention,
In such a case, it is considered that the heat conduction is abnormal,
Not subject to measurement. Therefore, the present invention attempts to obtain temperature conductivity by measuring the temperature difference between two points by going back to the non-steady region and then going back to the non-steady region. It is a means that utilizes the property that the conductivity does not affect the thermal conductivity.
【０００６】[0006]
【実施例】以下本発明の実施例を説明する。図１に示す
ように円柱形状をした物質１の内部に発熱体２と測温素
子３が埋設してある。発熱体２は自ら発熱し、かつ自ら
の温度を検出可能なものであり、例えば、金属細線を内
蔵した発熱センサー等が利用される。そして、これら発
熱体２と測温素子３により両者の温度差を計測する。図
２は物質１の内部中央に発熱体４を埋設し、この発熱体
４から異なる距離になるように二つの測温素子５、６を
配置した例を示しており、これら二つの測温素子５、６
によって両者の温度差を計測するものである。なお、例
えば発熱体４などの物質１内の特定点から二つの測温素
子５、６までの距離Ｌ１、Ｌ２はＬ１＜Ｌ２のときＬ２
／Ｌ１＞１（もしくはＬ２＜Ｌ１のときＬ１／Ｌ２＞
１）の関係になっている。なお、この場合の発熱体は物
質１の外部にあっても、二つの素子が異なる距離に保て
ば良いことは、いうまでもない。本発明にあっては図
１、図２の何れの構成を採ることもでき、何れにしても
物質内に生じている熱伝導を把握できれば良いものであ
るが、以下、図１に示すように発熱体２と測温素子３に
より温度差を計測するものについて説明する。物質１の
周りには冷却容器７が装着してある。８は冷却水入口、
９は冷却水出口である。このように物質１を冷却するの
は測定前において物質１の内部の場所によって異なる温
度域が生じ、温度勾配を生じるのを避けるためであり、
予め計測を行う前に冷却容器７に冷却水を流通させて物
質１の内部の温度を均一にする。EXAMPLES Examples of the present invention will be described below. As shown in FIG. 1, a heating element 2 and a temperature measuring element 3 are embedded inside a substance 1 having a cylindrical shape. The heating element 2 generates heat by itself and can detect its own temperature. For example, a heating sensor having a metal thin wire built therein is used. Then, the temperature difference between the heating element 2 and the temperature measuring element 3 is measured. FIG. 2 shows an example in which a heating element 4 is embedded in the center of the substance 1 and two temperature measuring elements 5 and 6 are arranged at different distances from the heating element 4. 5, 6
The temperature difference between the two is measured by. It should be noted that the distances L1 and L2 from a specific point in the substance 1 such as the heating element 4 to the two temperature measuring elements 5 and 6 are L2 when L1 <L2.
/ L1> 1 (or L1 / L2> when L2 <L1)
The relationship is 1). Needless to say, even if the heating element in this case is outside the substance 1, the two elements may be kept at different distances. In the present invention, either of the configurations shown in FIGS. 1 and 2 can be adopted, and in either case, it suffices to understand the heat conduction occurring in the substance. However, as shown in FIG. What measures the temperature difference by the heating element 2 and the temperature measuring element 3 will be described. A cooling container 7 is attached around the substance 1. 8 is a cooling water inlet,
9 is a cooling water outlet. The reason for cooling the substance 1 in this way is to avoid a temperature gradient that occurs due to different temperature regions depending on the location inside the substance 1 before measurement,
Before the measurement is performed in advance, the cooling water is passed through the cooling container 7 to make the temperature inside the substance 1 uniform.
【０００７】以上のようなものにおいて発熱体２を発熱
させて物質１の内部に熱伝導を生じさせると、測温素子
３で検出される温度もそれに追従して上昇する。こうし
て発熱体２と測温素子３により経時的に測温する。図３
において、曲線１０は発熱体２で検出される温度、曲線
１１は測温素子３で検出される温度、曲線１２はこれら
発熱体２と測温素子３の温度差をそれぞれ経時的に表し
たグラフである。図示のように、両者の温度差はある時
間を経過するとやがて一定の温度差Δθを保つようにな
り、準定常域となる。なお、図１の装置では物質１を外
部から冷却する冷却容器７を備えているので、両者の温
度差は準定常域となった後は一定の温度差Δθを保つこ
ととなるが、そのような冷却手段を備えていない場合に
は、発熱体２と測温素子３で検出される温度はそれぞれ
半永久的に上昇し続けることとなり、両者の温度差は次
第になくなる傾向を示す。そして、発熱体２と測温素子
３の温度差が一定温度差を保つようになったときの温度
差の値Δθを求める。次いで、発熱体と測温素子の温度
差が発熱開始から上記一定温度差Δθの１／Ｎの値に到
達するまでの時間Δｔを求める。なお、温度差は緩やか
に推移して行くので、一定温度差Δθとなったか否か、
即ち準定常域に到達したか否かを決定するには、例えば
演算装置を利用して差分法などによる数値解析で判定す
るとよい。また、Δｔが非定常域における時間となるよ
うにするために、Ｎの値は１より大きい値であることが
必要である。その理由は、上述したように定常域での熱
伝導は熱伝導率が影響するからであり、熱伝導が温度伝
導率に支配される非定常域において測定を行う必要があ
るからである。実施例においてはＮ＝２と定めている。
その主な理由はＮ＝２とすると計算が容易だからであ
る。When the heating element 2 is caused to generate heat in the above-mentioned case to cause heat conduction inside the substance 1, the temperature detected by the temperature measuring element 3 also rises following it. In this way, the temperature is measured with time by the heating element 2 and the temperature measuring element 3. Figure 3
In FIG. 10, a curve 10 is a temperature detected by the heating element 2, a curve 11 is a temperature detected by the temperature measuring element 3, and a curve 12 is a graph showing the temperature difference between the heating element 2 and the temperature measuring element 3 over time. Is. As shown in the figure, the temperature difference between the two eventually keeps a constant temperature difference Δθ after a certain period of time, and is in the quasi-steady region. Since the apparatus of FIG. 1 is provided with the cooling container 7 for cooling the substance 1 from the outside, the temperature difference between the two is kept constant after the quasi-steady region. Without such a cooling means, the temperatures detected by the heating element 2 and the temperature measuring element 3 continue to rise semipermanently, and the temperature difference between the two tends to gradually disappear. Then, the value Δθ of the temperature difference when the temperature difference between the heating element 2 and the temperature measuring element 3 maintains a constant temperature difference is obtained. Next, the time Δt from the start of heat generation until the temperature difference between the heating element and the temperature measuring element reaches the value of 1 / N of the constant temperature difference Δθ is calculated. Since the temperature difference gradually changes, whether or not the constant temperature difference Δθ is reached,
That is, in order to determine whether or not the quasi-stationary region has been reached, for example, it may be determined by a numerical analysis by a difference method or the like using an arithmetic device. In addition, the value of N needs to be a value larger than 1 so that Δt becomes the time in the non-steady region. The reason is that, as described above, the heat conductivity in the steady region is affected by the heat conductivity, and it is necessary to perform the measurement in the non-steady region in which the heat conductivity is governed by the temperature conductivity. In the embodiment, N = 2.
The main reason is that the calculation is easy when N = 2.
【０００８】また、以上のような測定において発熱体２
と測温素子３の距離Ｌが短くなると両者の温度差は小さ
くなる傾向を示す。図４は発熱体２と測温素子３の距離
Ｌと温度差の関係を示すグラフであり、曲線１３は両者
の距離Ｌが１０ｍｍの時の温度差を経時的に示すもので
あり、曲線１４は両者の距離Ｌが８ｍｍの時の温度差を
経時的に示している。曲線１５は発熱体の温度を経時的
に示している。図示のように、発熱体２と測温素子３の
距離Ｌが短くなると両者の温度差は小さくなるので、測
定時間を短くできるようになるが、非定常域において温
度差Δθの１／Ｎの値に到達するまでの間においては、
曲線１３と曲線１４は殆ど重複した格好になり、大きな
差が表れない。しかし、発熱体２と測温素子３の距離Ｌ
が短くなるはどＮは大きな値としたほうがよい。In the above measurement, the heating element 2
When the distance L between the temperature measuring element 3 becomes shorter, the temperature difference between the two tends to become smaller. FIG. 4 is a graph showing the relationship between the distance L between the heating element 2 and the temperature measuring element 3 and the temperature difference, and the curve 13 shows the temperature difference over time when the distance L between them is 10 mm, and the curve 14 Shows the temperature difference over time when the distance L between them is 8 mm. Curve 15 shows the temperature of the heating element over time. As shown in the figure, when the distance L between the heating element 2 and the temperature measuring element 3 becomes shorter, the temperature difference between the two becomes smaller, so that the measurement time can be shortened. However, in the non-steady region, the temperature difference Δθ is 1 / N. Until the value is reached,
The curves 13 and 14 are almost overlapped with each other, and a large difference does not appear. However, the distance L between the heating element 2 and the temperature measuring element 3
Although it becomes shorter, it is better to make N large.
【０００９】図５は発熱体２の発熱量を変えた場合の温
度差の変化を示したものである。発熱体２として金属細
線を内蔵した発熱センサーを使用し、図中曲線１６は印
加電圧が１.３Ｖの時の発熱体２の温度、曲線１６はそ
の時の発熱体２と測温素子３の温度差をそれぞれ示して
いる。また、曲線１８は印加電圧が１．４Ｖの時の発熱
体２の温度、曲線１９はその時の発熱体２と測温素子３
の温度差をそれぞれ示している。図示のように発熱量が
大きくなると準定常域に到達したときの温度差ΔＴも大
きく表れるようになり、測定時間は短くなる。なお、準
定常域に到達したときの温度差ΔＴの１／Ｎになるまで
の時間ΔｔはＮの設定により差の無い値を得ることが可
能である。FIG. 5 shows changes in the temperature difference when the amount of heat generated by the heating element 2 is changed. A heating sensor having a thin metal wire is used as the heating element 2. In the figure, a curve 16 is the temperature of the heating element 2 when the applied voltage is 1.3 V, and a curve 16 is the temperature of the heating element 2 and the temperature measuring element 3 at that time. The difference is shown respectively. A curve 18 is the temperature of the heating element 2 when the applied voltage is 1.4 V, and a curve 19 is the heating element 2 and the temperature measuring element 3 at that time.
The respective temperature differences are shown. As shown in the figure, when the calorific value increases, the temperature difference ΔT when reaching the quasi-steady region also becomes large, and the measurement time becomes short. It should be noted that the time Δt required to reach 1 / N of the temperature difference ΔT when the temperature reaches the quasi-steady region can be obtained by setting N so that there is no difference.
【００１０】以上のような測定を物性（温度伝導率を含
む）が既知の多数の物質について行い、各物質それぞれ
の温度差ΔＴの１／Ｎの温度差に到達するまでの時間Δ
ｔを計測して各物質の既知である温度伝導率から較正曲
線を定めたものが図６である。なお、測定は塩化ビニル
樹脂、有機質土、花崗岩、マグネシア、ニッケル、クロ
ム、ナトリウム、純銀、エチレングリコールの９種類の
物質について行い、発熱体２と測温素子３の温度差が一
定幅で安定したときの温度差ΔＴの１／２の温度差に到
達するまでの時間Δｔと各物質の既知である温度伝導率
ａとの関係を両対数グラフにプロットすることにより、
図中の較正曲線２０を得た。空気と水については実際に
測定せずに理論解析から求めた値をプロットした。ま
た、図１に示したように、測定対象物質を冷却容器７で
冷却して測定し、発熱体２と測温素子３の距離Ｌは９ｍ
ｍに設定した。なお、Ｎを２でない値に定めた場合や発
熱体２と測温素子３の距離Ｌを変えた場合には、図６と
異なる較正曲線となるので、そのような場合は改めて同
様の測定を行い較正曲線を定める必要がある。The above measurement is carried out for a large number of substances whose physical properties (including thermal conductivity) are known, and the time Δ until the temperature difference of 1 / N of the temperature difference ΔT of each substance is reached Δ
FIG. 6 shows the calibration curve determined from the known thermal conductivity of each substance by measuring t. The measurement was carried out on nine kinds of substances, vinyl chloride resin, organic soil, granite, magnesia, nickel, chromium, sodium, pure silver, and ethylene glycol, and the temperature difference between the heating element 2 and the temperature measuring element 3 was stabilized within a certain range. By plotting the relationship between the time Δt until reaching a temperature difference of 1/2 of the temperature difference ΔT and the known thermal conductivity a of each substance on a logarithmic log graph,
A calibration curve 20 in the figure was obtained. The values obtained from theoretical analysis were plotted without actually measuring air and water. Further, as shown in FIG. 1, the measurement target substance is cooled in the cooling container 7 and measured, and the distance L between the heating element 2 and the temperature measuring element 3 is 9 m.
set to m. When N is set to a value other than 2 or when the distance L between the heating element 2 and the temperature measuring element 3 is changed, a calibration curve different from that in FIG. 6 is obtained. In such a case, the same measurement is performed again. It is necessary to perform a calibration curve.
【００１１】次に、こうして求めた較正曲線２０に基づ
いて温度伝導率が未知の物質の温度伝導率を求める実験
を行った。その結果を以下に示す。 （実験例１）被測定物質として８０゜Ｃに加熱したサラ
ダ油に油凝固剤（商品名テンプル−ジョンソン株式会社
製）を１３．５ｇ／４００ミリリットルの割合で配合し
て常温に冷却したものを使用した。発熱体２と測温素子
３の距離Ｌを９ｍｍ、発熱体２の印加電圧を１．３Ｖと
し、発熱開始温度は常温である２７゜Ｃとした。図７は
その実験の結果を示すグラフであり、図中曲線２３は両
者の温度差を時間の経過と共に表したものである。この
実験において、発熱体２と測温素子３の到達した一定の
温度差ΔＴは２３゜Ｃであり、その１／２の値（１１．
５゜Ｃ）になるまでの時間Δｔは０．４分（２４．５
秒）であった。 この時間Δｔ（２４．５秒）から図６
の較正曲線２０を用いて点線２４のようにしてこの物質
の温度伝導率ａを求めたところ、０．５４×１０-3ｍ2
／ｈとなった。Next, based on the calibration curve 20 thus obtained, an experiment was carried out to find the temperature conductivity of a substance whose temperature conductivity is unknown. The results are shown below. (Experimental Example 1) As a substance to be measured, salad oil heated to 80 ° C was mixed with an oil coagulant (trade name: Temple-Johnson Co., Ltd.) at a ratio of 13.5 g / 400 ml and cooled to room temperature. did. The distance L between the heating element 2 and the temperature measuring element 3 was 9 mm, the applied voltage to the heating element 2 was 1.3 V, and the heat generation start temperature was room temperature, 27 ° C. FIG. 7 is a graph showing the results of the experiment, and the curve 23 in the figure shows the temperature difference between the two with the passage of time. In this experiment, the constant temperature difference ΔT reached by the heat generating element 2 and the temperature measuring element 3 was 23 ° C., and a half value (11.
Time Δt to reach 5 ° C is 0.4 minutes (24.5
Seconds). From this time Δt (24.5 seconds), as shown in FIG.
The thermal conductivity a of this substance was determined as indicated by the dotted line 24 using the calibration curve 20 of 0.54 × 10 −3 m 2
/ H.
【００１２】（実験例２）ゼラチン２０％のゲル試料を
用いてその温度伝導率を調べたところ、図８に示す温度
差の推移曲線が得られ、発熱体２が２５゜Ｃのとき発熱
体２と測温素子３の温度差ΔＴが２．８゜Ｃで安定し
た。これより、温度差ΔＴの１／２の値（１．４゜Ｃ）
になるまでの時間Δｔは０．２分（１２秒）であること
が解り、この時間Δｔ（１２秒）から図６の較正曲線２
０を用いてこの物質の温度伝導率ａを求めたところ、
１．１×１０-3ｍ2／ｈとなった。なお、測定は１／１
０００時間単位で行い、温度変化を記録したものであ
る。(Experimental Example 2) When the temperature conductivity of a gel sample of 20% gelatin was examined, the transition curve of the temperature difference shown in FIG. 8 was obtained, and when the heating element 2 was at 25 ° C, the heating element was heated. The temperature difference ΔT between 2 and the temperature measuring element 3 was stable at 2.8 ° C. From this, half the temperature difference ΔT (1.4 ° C)
It can be seen that the time Δt before reaching is 0.2 minutes (12 seconds), and from this time Δt (12 seconds), the calibration curve 2 in FIG.
When the thermal conductivity a of this substance was calculated using 0,
It was 1.1 × 10 −3 m 2 / h. The measurement is 1/1
The temperature change was recorded every 000 hours.
【００１３】次に、このようにして求められた温度伝導
率の真偽について考察する。既知文献である「分散系混
合物の有効温度伝導率」日本機械学会論文集（Ｂ編）５
６巻２１号（１９９０−１）によると、アクリルを母材
とし、酸化チタン（ＴｉＯ2 ）を分散材としたときの温
度伝導率比αｅ* 各材における容積比Φｖ（％）の関係
が示されている。 温度伝導率比 ＝ 分散材の温度伝導率 ／ 母材の温
度伝導率比 で示されており、この資料によれば、アクリルと酸化チ
タンの温度伝導率比は３５．４である。温度伝導率比は
無次元数なので、この比が上記資料に使用された母材
（アクリル）と同じとなるように配合した別の母材を使
用して分散材である酸化チタンとの分散混合物として温
度伝導率比を容積比との関係で調べたとき、上記資料の
母材（アクリル）における関係図と同じ傾向を示すもの
であれば別の母材の温度伝導率は正しいものであると判
断できる。先の実験例１で求められた食用油と凝固剤の
混合物の温度伝導率は図６の較正曲線から求めたもので
あるが、同様の実験により食用油と酸化チタンを混合し
たものについての温度伝導率を調べると図９のような結
果が得られた。この測定結果からこの混合物の温度伝導
率は０．８×１０-3（ｍ2 ／Ｈ）が導かれ、各濃度にお
ける温度伝導率比は図１０（表１）のようになった。な
お、酸化チタンの温度伝導率は３．０２ｍｍ2 ／ｓであ
ることからディメンションをあわせて計算すると容積比
０％のときの温度伝導率比は３５．５３であり、上記資
料と同じアクリルを母材とした混合物の比と同じである
ため比較が可能となる。Next, the authenticity of the thermal conductivity thus obtained will be considered. Known References "Effective Thermal Conductivity of Dispersed Mixtures" Proceedings of JSME (B) 5
According to Volume 6, No. 21 (1990-1), the relationship between the temperature conductivity ratio αe * and the volume ratio Φv (%) of each material when acrylic is used as the base material and titanium oxide (TiO 2 ) is used as the dispersion material is shown. Has been done. Thermal conductivity ratio = = thermal conductivity of dispersion material / thermal conductivity ratio of base material. According to this document, the thermal conductivity ratio between acrylic and titanium oxide is 35.4. Since the thermal conductivity ratio is a dimensionless number, a dispersion mixture with titanium oxide, which is a dispersion material, is used by using another base material compounded so that this ratio is the same as the base material (acrylic) used in the above material. As a result, when the temperature conductivity ratio is examined in relation to the volume ratio, if the same tendency as the relationship diagram for the base material (acrylic) in the above material is shown, the temperature conductivity of another base material is correct. I can judge. The temperature conductivity of the mixture of the edible oil and the coagulant obtained in the above Experimental Example 1 was obtained from the calibration curve of FIG. 6, but the temperature of the mixture of the edible oil and titanium oxide was determined by the same experiment. When the conductivity was examined, the results shown in FIG. 9 were obtained. From this measurement result, the temperature conductivity of this mixture was 0.8 × 10 −3 (m 2 / H), and the temperature conductivity ratio at each concentration was as shown in FIG. 10 (Table 1). Since the thermal conductivity of titanium oxide is 3.02 mm 2 / s, the thermal conductivity ratio when the volume ratio is 0% is 35.53 when the dimensions are calculated together. Since the ratio is the same as the ratio of the mixture used as the material, comparison is possible.
【００１４】図１１はこうして算出された温度伝導率比
を上記資料に示された温度伝導率比と容積比の関係図に
照合させたものを示しており、図示のように、母材がア
クリルである場合と実験例１のように母材が油である場
合において、一致していることがわかる。従って、上記
資料では分散系混合物において粒子容積比が０．２５以
下で求められる温度伝導率が適切値である結果を得てお
り、同容積比の範囲において資料における母材と同じ温
度伝導率である実験例１の食用油を母材とした結果の相
似性から実験例１の食用油の温度伝導率が適切であると
判断できる。もし、食用油の温度伝導率が実質的に異な
っていた場合は、分散系混合物にて温度伝導率の検証を
行った上記資料の方法に即した結果は、資料のアクリル
が示す温度伝導率比の傾向と異なった傾向を示し、食用
油の温度伝導率は間違いであると判断できる。つまりは
図６の較正曲線を利用して求めた物質の温度伝導率が適
切であり、較正曲線の利用について問題がないことが立
証される。ちなみに、寒天についても実験例のようにし
て温度伝導率を求めると、温度伝導率が０．１４７ｍｍ
2 ／ｓ（０．５２９×１０-3ｍ2 ／Ｈ）であり、これを
母材とする酸化チタンとの各容積比における温度伝導率
比を求めてみると、図１２（表２）のようになり、図１
１のごとく実験例１の油よりも小さな傾斜を示す。寒天
の場合は温度伝導率が実験例１の油よりも大きいことか
ら、その温度伝導率比は小さくなることが当然であり、
理論的な考察と実際とが相似した。FIG. 11 shows the temperature conductivity ratio calculated in this way, which is collated with the relationship diagram of the temperature conductivity ratio and the volume ratio shown in the above material. As shown in the drawing, the base material is acrylic. It can be seen that there is a match between the case of ## EQU1 ## and the case where the base material is oil as in Experimental Example 1. Therefore, in the above data, the temperature conductivity obtained when the particle volume ratio is 0.25 or less in the dispersion mixture is obtained as an appropriate value, and the same temperature conductivity as the base material in the data is obtained in the same volume ratio range. From the similarity of the results obtained by using the edible oil of Experimental Example 1 as a base material, it can be judged that the thermal conductivity of the edible oil of Experimental Example 1 is appropriate. If the thermal conductivity of the edible oil is substantially different, the results in accordance with the method of the above material that verified the thermal conductivity of the dispersion mixture are the thermal conductivity ratio indicated by the acrylic material. The tendency is different from that of the above, and it can be judged that the thermal conductivity of edible oil is wrong. That is, it is proved that the temperature conductivity of the substance obtained by using the calibration curve of FIG. 6 is appropriate, and there is no problem in using the calibration curve. By the way, the temperature conductivity of agar was 0.147 mm when it was calculated as in the experimental example.
2 is a /s(0.529×10 -3 m 2 / H), which Looking seek temperature conductivity ratio at each volume ratio of the titanium oxide as a base material, 12 (Table 2) As shown in Figure 1
1 shows a smaller inclination than the oil of Experimental Example 1. Since the thermal conductivity of agar is higher than that of the oil of Experimental Example 1, it is natural that the thermal conductivity ratio is small.
The theoretical consideration and the actual were similar.
【００１５】なお、以上においては、Ｎ＝２とした場合
の各種実験結果を示したが、Ｎを２でない値に定めた場
合や発熱体２と測温素子３の距離Ｌを変えた場合には、
図６と異なる較正曲線となるので、そのような場合は改
めて同様の測定を行い較正曲線を定める必要があること
は上記した通りである。但し、Ｎ＞１とすることが条件
である。なお、もし被測定物質において環境温度が激し
く変化して物質自体の温度も変化し、それによって温度
伝導率も変化するような場合には、各温度における温度
差の１／Ｎの温度差に到達する時間と温度伝導率の相関
関係を予め得ておくなどの方法により、その相関関係か
ら温度伝導率を決定する手段も考えられる。In the above, various experimental results are shown when N = 2, but when N is set to a value other than 2 or when the distance L between the heating element 2 and the temperature measuring element 3 is changed. Is
Since the calibration curve is different from that in FIG. 6, in such a case, it is necessary to perform the same measurement again to determine the calibration curve, as described above. However, the condition is N> 1. If the ambient temperature of the substance to be measured changes drastically and the temperature of the substance itself also changes, which also changes the thermal conductivity, a temperature difference of 1 / N of the temperature difference at each temperature is reached. A method of determining the temperature conductivity from the correlation by a method of previously obtaining the correlation between the time and the temperature conductivity is also conceivable.
【００１６】[0016]
【発明の効果】本発明によれば、各種設計基礎値や製品
品質の安定のための物性値として重要な温度伝導率を迅
速に求めることができ、各種材料、原料の熱拡散の状況
や状態を迅速に把握できる。密度や比熱が既知の物質の
場合には熱伝導率を参照にすることもできるが、この様
な物性値は多くの場合は不明であり、本発明のように温
度伝導率を求めて熱拡散の状況や状態を把握することが
最も適当である。その具体例としては、例えば、パルプ
原料の調合における材料の温度伝導率の制御や食品原料
の調合における熱変質の防止のための制御用基礎値、樹
脂加工等における加熱時間の制御基礎値等を得る場合な
どをあげることができる。また、各種形状物、特に食品
などにおいて製品を冷却や加熱操作する際の熱拡散の状
況や状態が把握できるようになり、製品形状や包装形
態、加熱、冷却時間の設定や加熱、冷却装置の能力、形
式の決定などの基礎値として温度伝導率を利用できる。
即ち、従来はこれらを決定する場合、経験的な把握や安
全率を高くしてカバーするようにしているが、本発明に
よれば製品の出来高や生産速度を加味して適切な設計が
可能になるので、エネルギーの省力化やコストの低減を
図ることができる。また、本発明によれば従来行われて
いる温度伝導率の測定法であるオングストローム法やフ
ラッシュ法に比較して測定装置の規模が小さくて済み、
加えて製造工程などにおけるインラインでの計測ができ
るようになる。しかも、計測装置が簡単に構成でき、保
守もしやすい利点がある。EFFECTS OF THE INVENTION According to the present invention, it is possible to quickly obtain the temperature conductivity which is important as a physical property value for stabilizing various design basic values and product quality, and the thermal diffusion state and state of various materials and raw materials. Can be grasped quickly. In the case of a substance whose density and specific heat are known, it is possible to refer to the thermal conductivity, but such physical property values are unknown in many cases, and thermal diffusion is performed by calculating the thermal conductivity as in the present invention. It is most appropriate to understand the situation and condition of. Specific examples thereof include, for example, a control basic value for controlling the temperature conductivity of materials in the preparation of pulp raw materials and for preventing thermal alteration in the preparation of food raw materials, a control basic value for heating time in resin processing, etc. When you get it, you can list it. In addition, it becomes possible to grasp the state and state of heat diffusion when cooling or heating products in various shapes, especially food etc., product shape and packaging form, heating, setting of cooling time and heating, cooling device Thermal conductivity can be used as a basic value for determining capacity and type.
That is, in the past, when determining these, the empirical grasp and the safety factor are increased to cover, but according to the present invention, an appropriate design can be performed in consideration of the product volume and the production speed. Therefore, energy saving and cost reduction can be achieved. Further, according to the present invention, the scale of the measuring device can be smaller than that of the conventional method of measuring the thermal conductivity, such as the angstrom method or the flash method,
In addition, in-line measurement can be performed in the manufacturing process. Moreover, there is an advantage that the measuring device can be easily configured and is easy to maintain.
【図面の簡単な説明】[Brief description of drawings]
【図１】本発明方法を実施するための測定装置の部分断
面図FIG. 1 is a partial sectional view of a measuring device for carrying out the method of the present invention.
【図２】本発明方法を実施するための測定装置の部分断
面図FIG. 2 is a partial sectional view of a measuring apparatus for carrying out the method of the present invention.
【図３】発熱体と測温素子で検出される温度、発熱体と
測温素子の温度差をそれぞれ経時的に表したグラフFIG. 3 is a graph showing the temperature detected by the heating element and the temperature measuring element and the temperature difference between the heating element and the temperature measuring element over time.
【図４】発熱体と測温素子の距離と温度差の関係を示す
グラフFIG. 4 is a graph showing the relationship between the distance between the heating element and the temperature measuring element and the temperature difference.
【図５】発熱体の発熱量と温度差の関係を示すグラフFIG. 5 is a graph showing the relationship between the calorific value of the heating element and the temperature difference.
【図６】時間Δｔと温度伝導率の較正曲線を示すグラフFIG. 6 is a graph showing a calibration curve of time Δt and thermal conductivity.
【図７】実験例１の測定結果を示すグラフFIG. 7 is a graph showing the measurement results of Experimental Example 1.
【図８】実験例２の測定結果を示すグラフFIG. 8 is a graph showing the measurement results of Experimental Example 2.
【図９】食用油と酸化チタンを混合したものについての
温度伝導率を示すグラフFIG. 9 is a graph showing the thermal conductivity of a mixture of edible oil and titanium oxide.
【図１０】食用油と酸化チタンを混合したものについて
の各濃度における温度伝導率比を示す表１FIG. 10 is a table 1 showing a thermal conductivity ratio at each concentration for a mixture of edible oil and titanium oxide.
【図１１】温度伝導率比を照合させたグラフFIG. 11 is a graph in which the thermal conductivity ratio is collated.
【図１２】寒天についての各濃度における温度伝導率比
を示す表２FIG. 12 is a table 2 showing the thermal conductivity ratio of agar at various concentrations.
１ 物質 ２、４ 発熱体 ３、５、６ 測温素子 1 substance 2, 4 heating element 3, 5, 6 temperature measuring element
Claims (4)
二つの測温素子を物質内に配置し、発熱体を発熱せしめ
てそれら測温素子の温度差が一定温度差を保つようにな
ったときの該温度差を求め、それら測温素子の温度差が
発熱体の発熱開始から前記一定温度差の１／Ｎの値に到
達するまでの時間から物質の温度伝導率を得ることを特
徴とする温度伝導率の計測方法。1. When at least two temperature measuring elements located at different distances from a heating element are arranged in a substance and the heating element is caused to generate heat so that the temperature difference between the temperature measuring elements maintains a constant temperature difference. The temperature difference is obtained, and the temperature conductivity of the substance is obtained from the time from the start of heat generation of the heating element until the temperature difference of the temperature measuring elements reaches the value of 1 / N of the constant temperature difference. Method of measuring conductivity.
な発熱体内蔵もしくは兼用素子と測温素子を物質内に配
置し、発熱体を発熱せしめて発熱体と測温素子の温度差
が一定温度差を保つようになったときの該温度差を求
め、発熱体と測温素子の温度差が発熱開始から上記一定
温度差の１／Ｎの値に到達するまでの時間から物質の温
度伝導率を得ることを特徴とする温度伝導率の計測方
法。2. A heat-generating element built-in or capable of detecting its own temperature or a dual-purpose element and a temperature measuring element are arranged in a substance, and the heat generating element is caused to generate heat so that a temperature difference between the heat generating element and the temperature measuring element is generated. The temperature difference is calculated when the constant temperature difference is maintained, and the temperature of the substance is measured from the time from the start of heat generation until the temperature difference between the heating element and the temperature measuring element reaches 1 / N of the constant temperature difference. A method for measuring thermal conductivity, characterized by obtaining conductivity.
または２に記載の温度伝導率の計測方法。3. The N is a value greater than 1.
Alternatively, the method for measuring the thermal conductivity described in 2.
項１乃至３の何れかの方法で各物質の温度差の１／Ｎの
温度差に到達する時間を計測して各物質の既知である温
度伝導率から較正曲線を定め、この較正曲線に基づいて
温度伝導率が未知の物質の温度伝導率を求めることを特
徴とする温度伝導率の計測方法。4. A method of measuring the time required to reach a temperature difference of 1 / N of the temperature difference of each substance by the method according to any one of claims 1 to 3 by using two or more substances whose physical properties are known. A method for measuring thermal conductivity, characterized in that a calibration curve is determined from a known thermal conductivity, and the thermal conductivity of a substance whose thermal conductivity is unknown is determined based on this calibration curve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30403491A JP2959895B2 (en) | 1991-10-23 | 1991-10-23 | How to measure temperature conductivity |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30403491A JP2959895B2 (en) | 1991-10-23 | 1991-10-23 | How to measure temperature conductivity |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05119003A true JPH05119003A (en) | 1993-05-14 |
| JP2959895B2 JP2959895B2 (en) | 1999-10-06 |
Family
ID=17928265
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30403491A Expired - Lifetime JP2959895B2 (en) | 1991-10-23 | 1991-10-23 | How to measure temperature conductivity |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2959895B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5772321A (en) * | 1995-10-25 | 1998-06-30 | Hewlett-Packard Company | Compensation for spacial and temporal temperature variations in a thermal conductivity detector |
| DE10206045B4 (en) * | 2002-02-14 | 2006-12-14 | Bundesrepublik Deutschland, vertr. d. d. Bundesministerium für Wirtschaft und Technologie, dieses vertr. d. d. Präsidenten der Physikalisch-Technischen Bundesanstalt | Quasi-stationary method for measuring the thermal conductivity |
| JP2015502548A (en) * | 2011-12-21 | 2015-01-22 | インスティテュート ドゥ ラディオプロテクション エ ドゥ シュルテ ヌクレア | Process for estimating thermophysical value of material, measurement process including the estimation process, and self-adjusting flow meter |
-
1991
- 1991-10-23 JP JP30403491A patent/JP2959895B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5772321A (en) * | 1995-10-25 | 1998-06-30 | Hewlett-Packard Company | Compensation for spacial and temporal temperature variations in a thermal conductivity detector |
| DE10206045B4 (en) * | 2002-02-14 | 2006-12-14 | Bundesrepublik Deutschland, vertr. d. d. Bundesministerium für Wirtschaft und Technologie, dieses vertr. d. d. Präsidenten der Physikalisch-Technischen Bundesanstalt | Quasi-stationary method for measuring the thermal conductivity |
| JP2015502548A (en) * | 2011-12-21 | 2015-01-22 | インスティテュート ドゥ ラディオプロテクション エ ドゥ シュルテ ヌクレア | Process for estimating thermophysical value of material, measurement process including the estimation process, and self-adjusting flow meter |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2959895B2 (en) | 1999-10-06 |
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