Topology Optimization of Heat-resistant Structures

The standard problem of finding the optimal layout of structural material associated with maximum stiffness is expanded to include consideration of thermal criteria. The problem is posed as a three-phase layout problem where the phases include an insulating or fire retardant material and an unknown distribution of heat sources, in addition to the structural material. The model used is simple, yet results suggest that the introduction of measures to control the temperature in the structure when subjected to significant heat transfer rates can result in layouts that differ substantially from solutions where thermal issues are ignored. Fires typically involve two steps: ignition and flame. Flame propagation, which often follows ignition, occurs by heating of the adjacent materials to the point where the volatiles released by the degradation of the solid materials can be used as fuel. The mechanisms associated with the release of the volatiles are quite complex and involve two distinct processes: fuel generation in the solid phase and combustion in the gas phase. Radiation from the flame, conduction or convection through the gas from the flame and conduction through the solid are three important mechanisms -besides external sourcesthat control the rate of flame spread