Mechanical Characteristics of Vacuum Thermal Insulation Panels: Deformation Diagrams, Strength, Deformation Modules

Abstract

The results of studying the mechanical properties of vacuum insulation panels are presented. The compressive strength and deformation modules (elastic and secant) under compression and shear are determined. The dependence of the mechanical characteristics of vacuum insulation panels (VIP) on the type and quantitative ratio of fillers is shown. It is established that the diagram of deformation of the VIP under compression can be described by an analytical function. Experimental studies of the properties of VIP have established that the deformation diagram of VIP has the form characteristic for materials that self-strengthen during loading with a compressive load and is adequately described by the function of G. V. Bulfinger. A method is proposed for determining the coefficients α and β that makes it possible to verify the approximating function using experimental data. Polynomial models describing the dependence of the elastic modulus, strength, and thermal conductivity coefficient on the composition and quantitative ratio of fiber and powder fillers are developed. It is established that the numerical values of the strain modulus depend on the type, amount of powder filler, and their ratio to the fibrous filler. The values of strain and strength models increase with increasing content and size of filler particles. A method for determining the shear modulus for VIP has been developed. It has been experimentally established that the value of the shear modulus for VIP depends on both the filler composition and the characteristics of the panel film shell. Keywords: vacuum insulation panel, diatomite, silica fume, thermal conductivity, strength, compression, shear, modulus of deformation.