Modeling the Laser Flash Method for Thermal Characterization of Fat Tissue Mimicking Phantom

This paper describes a computational implementation of the laser flash method to determine the thermal conductivity of fat tissue in the software COMSOL Multiphysics, the simulated laser generates a transient temperature rise. By measuring the time that it takes for the heat to be distributed throughout the material, the thermal diffusivity coefficient can be determined, and the thermal conductivity can be calculated. This is important for predicting the heating effects in hyperthermia treatments where heat absorption and dissipation in adipose tissues are involved. The design of a 2D geometry simplifies the computational load by reducing the model's complexity. It also enables the implementation of boundary conditions that simulate the heat source as a Gaussian laser beam and the thermal insulation to emulate an adiabatic environment. As a result, the time it took to reach half of the maximum temperature was 1.416 s, which differs from the theoretical value. Considering the absorption coefficient (µa) in the model with a thermal conductivity of 0.21 W m<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup>K-<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup>, the error decreases from 5.34 % to 0.162 %. Despite this, the model presents a methodology for the thermal characterization of a phantom composed of adipose tissue in the absence of a thermal analyzer.