The non-Fourier effects on transient temperature response in semitransparent medium with black boundary surfaces caused by laser pulse are studied. The processes of the coupled conduction and radiation heat transfer in a one-dimensional semitransparent slab with black boundaries are analyzed numerically. The hyperbolic heat conduction equation is solved by the flux-splitting method, and the radiative transfer equation is solved by the discrete ordinate method. The transient temperature response obtained from hyperbolic heat conduction equation is compared with those obtained from the classical parabolic heat conduction equation. The results show that the non-Fourier effect can be important when the conduction-to-radiation parameter and the thermal relaxation time of heat conduction are larger. Under this condition, for the laser-flash measurement of the thermal diffusivity in semitransparent materials, omitting the non-Fourier effect can result in significant errors.

The transient thermal responses in a two-dimensional semitransparent cylinder with black boundary surfaces caused by a pulse irradiation at one end of the cylinder are studied. The processes of the transient coupled radiative-conductive heat transfer in the cylinder are analyzed numerically. An implicit central-difference scheme is employed for handling the energy equation, while a discrete-ordinates method is used to solve the radiative transfer equation. The effects of various parameters on the transient thermal responses are investigated. It is found that, due to the radiation within medium, the transient temperature of the nonirradiated end surface of the cylinder can be greater than that of the inner medium of cylinder. Temperature evolution curves with two peaks can be observed under some conditions at the nonirradiated end of the cylinder. The effects of the conduction-radiation parameter, the optical thickness and refractive index on the transient temperature responses are large. The effects of single-scattering albedo are more significant for the radiation-dominated case than that for the conduction-dominated case.

The non-Fourier effects on transient thermal response in semitransparent medium with black boundary surfaces caused by a periodic irradiation are studied. The processes of the transient coupled radiative-conductive heat transfer in a one-dimensional semitransparent slab with black boundaries are analyzed numerically. The hyperbolic heat conduction equation is solved by the flux-splitting method, and the radiative transfer equation is solved by the discrete ordinate method. The transient thermal responses obtained from hyperbolic heat conduction equation are compared with those obtained from the classical parabolic heat conduction equation. The results show that the non-Fourier effect can be important when the conduction-to-radiation parameter and the thermal relaxation time of heat conduction are larger. The non-Fourier effect can be important even at a long time after the initial transient if the periodic irradiation at boundary is oscillatory with the period of oscillation of the same order of magnitude as the thermal relaxation time of conduction.

The internal distribution of spectral radiation absorption in a semitransparent spherical particle irradiated uniformly and isotropically is determined by the ray tracing method, and the detailed computation formulae for the internal spectral radiation absorption are deduced. The computed results show that the peak of internal volumetric spectral radiation absorption may locate at the interior shell of the particle. The dimensionless volumetric spectral radiation absorption is higher near the center for weakly absorbing or small spheres, but the dimensionless volumetric spectral radiation absorption is higher near the surface for strongly absorbing or large spheres. The corresponding physical interpretations of the internal spectral absorption distribution are given.

The internal distribution of spectral radiation absorption in one-dimensional semitransparent slab, sphere and cylinder irradiated uniformly and isotropically is determined by the ray tracing method, and the detailed theory for computation are deduced. The computed results show that the internal distribution of spectral radiation absorption in slab differs from that in spherical and cylindrical particles. The peak of internal volumetric spectral radiation absorption may locate at interior shell of the semitransparent sphere and cylinder. The dimensionless volumetric spectral radiation absorption is higher near the center for weakly absorbing or small size parameter, but is higher near the surface for strongly absorbing or large spheres and cylinders. Refraction focuses the rays close to the sphere and cylinder center. With the increases of the refractive index, the dimensionless volumetric spectral radiation absorption increases near the sphere and cylinder centers and decreases near the sphere and cylinder surfaces.