Study on heat transfer characteristics of hollow composite thermal barrier structure at high temperature

Air interlayers are often used as a part of thermal insulation structure and form a system with solid materials to reduce heat transfer. However, the heat transfer process in the composite structure is affected by many factors at high temperatures. In this paper, a series of heat preservation systems with air gap and solid structure were proposed. Based on the research background of heat preservation in the riser of ingot casting, the heat transfer process in the composite structure was systematically studied by means of numerical simulation and experiment. The heat transfer laws under different geometric structures, thermophysical properties of materials, and surface emissivity were obtained, which could provide theoretical basis for the design of heat preservation structures at high temperatures.