In order to measure thermal conductivities by the un-steady state relative method under the condition of periodic heating, basic items were considered.
First, with the consideration that a system composed of standard sample (Acryl resin plate, thickness of 5 mm) and unknown sample (Rice grain layer, thickness of semi-infinite) has one contact surface perpendicular to the direction of heat flow, one-dimensional periodic heat conduction was studied numerically. From this, it was shown that the equation (27) derived in paragraph 2-3 is the most appropriate in accuracy to approximate temperatures at the contact surface.
Next, conserning the sensitivity of thermocouples the length of the period of given temperature wave was studied to hold the errors of numerical solutions less than 2% or so. Frorn this result, it has been concluded that if an experiment is conducted under the temperature wave period of t₀, 118(sec)≦t₀≦284(sec), the solutions calculated by using the measured data will satisfy the expected accuracy, in the case that the materials assumed in this calculation are used.
When materials different from those aforementioned are used, their thermal properties are also different from those shown in Table 1. Hence, the error of numerical solutions will show other values. Nevertheless, the relationship between each discretization equation and its accuracy shows a similar tendency.
However, when not only the accuracy of numerical solutious but also the volume of calculation become problems, not the equation (27) but the equation (21) may become more appropriate in some cases.
Therefore, the most appropriate discretization equation should be selected according to materials used.
雑誌名
三重大學農學部學術報告 = The bulletin of the Faculty of Agriculture, Mie University
巻
68
ページ
97 - 103
発行年
1984-03-01
ISSN
0462-4408
書誌レコードID
AN00234337
フォーマット
application/pdf
著者版フラグ
publisher
その他のタイトル
Conduction of Heat through the Contact Surface between Grain Layer and Different Material : Basic Numerical Analysis for Measurement of Thermal Conductivity
穀物と異種材料間の熱伝導 : 熱伝導率測定のための基礎的数値解析
AN002343370006809.pdf
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