| 摘要 |
In order to measure the thermal conductivity lambda of a thermally conducting or insulating material, a test piece of thickness e and cross-sectional area S is placed in a conductimeter, and it is subjected to a preliminary test during which it is heated to a temperature <IMAGE> [lacuna] temperature and the temperature difference for which it is desired to take the measurement. The temperature difference DELTA TP between the two faces of the test piece are then noted. During a subsequent measurement test, the temperature of one of the faces of the test pieces is lowered by DELTA PHI , and the other face is kept at the temperature previously measured, by supplying a heat flux Q to it. The new temperature difference DELTA TM between the faces of the test piece is observed, and the thermal conductivity lambda is deduced therefrom, using the relationship lambda = Qe DIVIDED S( DELTA Tm- DELTA Tp). <IMAGE>
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