Thermal conductivity of hollow microspheres with perforated walls

Abstract

One of the main directions of scientific research in the field of materials is the study of the thermophysical properties of composite materials and heterogeneous systems. Understanding these properties and developing analytical forecasting methods are necessary to create materials with the required properties. For the first time, the thermal conductivity of hollow microspheres with perforated walls is investigated as a necessary component of promising new composites. The purpose of this work is to evaluate the possibility of analyzing the effective thermal conductivity of hollow perforated microspheres at the stage of their development. The relations for the analytical evaluation (calculation/forecast) of the effective thermal conductivity of hollow microspheres with different wall materials, types of gas in the pores (air or other gases) and the relative perforation area of the walls of hollow microspheres are obtained. To calculate the thermal conductivity of an object, models and methods of the theory of generalized conductivity are used. The results of the analytical calculation of the values of the effective thermal conductivity of microspheres made of Al2O3, ZrO2, diethylpolysiloxane filled with air, depending on the relative thickness of the microsphere wall and the relative perforation area of the walls at fixed temperatures are presented. The results of the work can be used to predict the properties of new composite materials in a predetermined temperature range.