Vibrations in engineering and technology

Tsurkan Oleh – Doctor of Technical Sciences, Associate Professor, Director of Separate structural subdivision «Ladyzhyn vocational college of Vinnytsia National Agrarian University» (Kravchik Petro St., 5, Ladyzhyn, Vinnytsia Region, Ukraine, 24321, e-mail: tsurkan_ov76@ukr.net).

Spirin Anatoly - candidate of technical sciences, associate professor, teacher of Separate structural subdivision «Ladyzhyn vocational college of Vinnytsia National Agrarian University» (Kravchik Petro St., 5, Ladyzhyn, Vinnytsia Region, Ukraine, 24321, e-mail: spirinanatoly16@gmail.com.

Tverdokhlib Igor – candidate of technical sciences, associate professor of the department of general technical disciplines and occupational safety, Vinnytsia National Agrarian University: Vinniytsia, st. Sonyachna 3, VNAU, 21008, e-mail: igor_tverdokhlib@yahoo.com.

Crop products require good moisture content for successful storage. The drying process is mainly used for this purpose. For its successful design and implementation it is necessary to have information about the physical and mechanical properties of the material, including thermo physical characteristics. It is for the successful implementation of the process of post-harvest processing of pumpkin seeds were planned and conducted experimental studies.

Analysis of previous studies to determine the thermo physical characteristics of various materials, including plant products, showed that in most cases one series of experiments to determine three main indicators - heat capacity, thermal conductivity and thermal conductivity of products. Unfortunately, there is no universal method and installation for determining the required indicators, so in our research we used the original installation, the principle of which is based on the use of non-stationary heating patterns of two semi-bounded rods, where the source of heat is constant power.

The theoretical basis of the implemented method is the solution and analysis of the thermal equation with the corresponding boundary conditions. Intermediate equations were obtained from which the values of thermal conductivity and thermal conductivity for each series of experiments were found by the graph-analytical method of solution. The value of heat capacity of the material was determined from the well-known formula of the ratio of these three indicators. As a result of research and processing of the obtained data, the dependences of the thermo physical properties of the material on its humidity were determined, which are presented in graphical and analytical form. The obtained dependences confirmed the results of researches of some authors on the presence of inflection in the graph of thermal conductivity which is explained by the transition of moisture from free to bound state.

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