International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

In this paper, analytical expressions are obtained for determining the temperature distribution in a two-layer medium with local heating concentrated on the interface surface of the layers for a stable and linearly variable relative to the temperature of the thermal conductivity coefficient of the materials of the layers. Numerical calculations are given, and on this basis, the curves of temperature distribution as a function of spatial coordinates were constructed, which make it possible to
analyze the temperature regimes in a two-layer plate.

The article presents a study of the sound and thermal insulation properties of ceramic plates with cavities, designed for beehives. The plates are obtained by the “casting” method from a water-dispersed colloidal system based on a patent-protected quartz glass-ceramic. They are composed of amorphous SiO2, mullite and cristobalite. To measure the thermal conductivity, a thermal chamber is constructed with a heater installed in it. Given that the heat flow passing through the three-layer ceramic plate for beehives is constant, the temperature difference between the two opposite sides of the plate at steady state (at constant heat flow) is measured and the thermal conductivity is calculated. A two-chamber method is used to determine the sound insulation capacity of the ceramic plates for beehives. The sound pressure of the sound waves – the incident one and of the wave which has passed through the sample –is measured in the frequency range from 100 to 3150 Hz