Analysis of heat transfer characteristics of sandwich cylindrical shell with an aerogel-metal-rubber composite core

Abstract

Metal-rubber sandwich cylindrical shell displays a broad range of potential applications in the field of thermal insulation due to its advantages of lightweight, high-temperature stability, and superior high-temperature thermal insulation properties. To optimize the thermal insulation performance of a sandwich cylindrical shell with a metal-rubber core, this study proposes the idea of filling the pores of the metal-rubber with aerogel, thereby forming a composite structure of aerogel and metal-rubber (AMR). Through finite element analysis, the law of internal temperature changes in the AMR composite structure and the distribution laws of the velocity field, viscosity field, and pressure field of the sandwich cylindrical shell under varying wind speeds are investigated. These findings are further verified through heat transfer and forced convection tests. The results reveal that the thermal conductivity of the AMR composite structure at the same density is lower than that of the metal-rubber, and the thermal insulation performance of the AMR composite structure is directly proportional to its density. Meanwhile, through the analysis of forced convection heat transfer in the cylindrical shell, it is found that wind speed has a direct relationship with the pressure field, velocity field, and viscosity field. In addition, there is a relatively high viscosity and a low flow rate near the wall of the cylindrical shell, with a higher flow rate at the axis of the cylindrical shell. At the same wind speed, the temperature rise of the sandwich cylindrical shell shows a positive correlation with an increase in density, and the maximum stable temperature also increases correspondingly. Moreover, at the same density, the thermal conductivity demonstrates a negative correlation with increasing temperature.