Method and a Measuring Unit for Monitoring Thermophysical Characteristics of Heterogeneous Plant Origin Materials

The paper introduces a method and tools for measuring thermophysical characteristics (TPC) of heterogeneous materials which are essentially plant tissues of vegetables and fruits. The method proposed is advantageous as it provides non-destructive thermal control over surface areas of plant objects with lesions that have resulted from phyto-diseases or mechanical effects. When in the process of measuring the thermal conductivity and thermal diffusivity coefficients of plant tissues, the test sample is heated to 10...15 K at the power up to 3500 W/m² and during the time up to 1 minute, the original properties of the research subject are retained. Calibration on standard samples showed that the error in measuring thermophysical characteristics does not exceed 10 %, and for the thermal conductivity coefficient it is not more than 7 %. Experiments with potato plant tissue revealed a difference in thermophysical characteristics of healthy and damaged tuber tissues as a result of some phyto-diseases

The work was supported by the Ministry of Education and Science of the Russian Federation under the agreement no. 14.577.21.0214 (PNIER RFMEFI57716X0214)

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