Numerical investigation of thermal diffusivity prediction based on analytical solution of transient heat conduction
In this study, the analytical solution of one-dimensional transient heat conduction along the radius direction in an infinitely long cylinder is reformulated to predict thermal diffusivity. Burggraf (JHT, 1964) presented an equation that depicts the relation among the temperature at radius r (r ≠ 0), the temperature at the center, and thermal diffusivity. On the basis of this equation, the temperature at the center (r = 0) and R/2 of the cylinder are used as the input data to obtain a nonlinear function of thermal diffusivity. The solution of this function provides the thermal diffusivity under different temperatures. Simulation results show that for a specified cylinder radius, optimal heat transfer conditions exist for obtaining accurate thermal diffusivity results. This study indicates that the temperature-dependent thermal diffusivity may be estimated in one experiment, and the heat transfer coefficient outside the cylinder can be calculated simultaneously. On the basis of this model, a thermal diffusivity measuring method can be developed.