Modeling for the Transient Radiative Properties of Alumina Particles with Phase Transition

Abstract

Nomenclature F x = volume fraction of the x component in the whole particle f = portion of the phase during the transition from the phase to the phase I = particle's spectral radiance k = imaginary part of the complex refractive index (absorption coefficient) m = complex refractive index of the mixture M x = portion of the x phase in the whole particle m x = complex refractive index of the x component n = real part of the complex refractive index (refractive index) Q abs; = absorption factor of the particle r = radius of the particle r L = equivalent radius of the liquid fraction of the particle r s = equivalent radius of the solid fraction of the particle r s = relative crystallization-front radius T m = equilibrium melting temperature T s = crystallization-front temperature V x = volume of the x component t = time step " = spectral emissivity of the particle " x = dielectric constant of the x component " = dielectric constant of the mixture " d = dielectric constant of the host medium Subscripts L = liquid phase = alpha phase = gamma phase