关键词: 固体材料, 热物性测算模型, 平行热线法, 镜像热源法, 测试系统

Abstract: Based on the parallel hot-wire method and the principle of enantiomorphous heat-source, a new model for measuring the thermophysical parameters of solid materials was proposed. On the basis of the principle of hotline test, the existence of virtual mirror heat-source at the symmetrical position of the real heat-source was taken as the boundary of the adiabatic boundary of the specimen, so as to eliminate the influence of the heat accumulation effect caused by the adiabatic boundary. Therefore, the test can no longer limit the experimental time and sample thickness. When the calculation results of the thermal physical parameters in the adjacent time were greater than that of the criteria proposed, the mirror heat-source was introduced to correct the calculated temperature. In order to avoid the dependence of the thermal physical parameters on the calculated value at the initial stage of the experiment, the measured temperature was corrected by the model two times. Asbestos as the research object, through the theoretical analysis combined with numerical calculation, shows that there was a difference between the two correction results, but the difference was not large and the second correction of the thermophysical parameters of the calculation results more stable. The thermal property test applied to the asbestos board, marble, borosilicate glass, silica brick and other 4 kinds of thin and thick material. The results showed that it was consistent with the measured values of other methods in the literature, and the maximum error was less than 5%. This test method was validated for the thin plate samples and thick plate samples, effectively improving the hot wire method test accuracy and expanding the scope of application.

Key words: solid material, thermo-physical parameters, parallel hot wire method, enantiomorphous heat-source, measurement system