Determination of Thermal Conductivity by the Method of the Initial Stage of Warming up a Sample by a Constant Heat Flux.

A method of determining the thermal conductivity of a sample at the initial stage of its warming up is presented. The approach is based on the solution of the problem of heating a plane-parallel infinite plate by a constant heat flux. The description of the theoretical base, solution of the problem, and derivation of the working computational formula are given. The main difference of the developed method from the traditional stationary method of determining thermal conductivity is the use of the initial region of the thermogram of sample warming up. This substantially reduces the time of experiments to several minutes. To realize the method, an automated installation has been devised, and the description of its scheme, algorithm, and of the software composition is given. The automation was made on the base of the computer-aided measuring system "Aksamit 6.25" and a PC. The advantages of the developed method and of the automated installation consist of the substantial reduction of the experiment duration with preservation of the needed uncertainty and error of measurement. [ABSTRACT FROM AUTHOR]