In solving the system of hyperbolic equations, numerical methods that are easy to apply, have high accuracy, do not cause numerical oscillations, and have a shorter runtime are more popular. In the present study, the space-time conservation element and solution element (CESE) method has been developed in 2-D spherical coordinates using polar elements. The developed CESE method has been applied to investigate non-Fourier thermal wave propagation in biological tissue. In order to evaluate the performance of the CESE method, the numerical results have been compared with the existing semi-analytical results and it is observed that the results are completely consistent. The experiment test is then performed to measure the transient temperature behavior of the spherical Intralipid phantom irradiated by a NIR pulsed laser. Comparison of experimental and numerical results shows the applicability of dual phase lag (DPL) model in predicting non-Fourier heat conduction in the tissue. Then, the contours of heat fluxes and temperature during and after laser irradiation are presented and the thermal wave propagation inside the tissue is examined and discussed. The results show that the effects of 2-D thermal wave appear after stopping the laser irradiation. In the following, the study of the effect of tissue type on wave progression in tumor, muscle, and fat demonstrates that in the fat tissue, which has the lowest thermal diffusivity, the thermal progression is less than the tumor and muscle, but the temperature distribution is more than the other tissues.

Keywords