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The Key Role of Thermal Relaxation Time on the Improved Generalized Bioheat Equation: Analytical Versus Simulated
Alexandra Maria Isabel Trefilov1, Mihai Oane1, Liviu Duta1
1National Institute for Laser, Plasma and Radiation Physics, 077125 Magurele, Romania.
This study develops an advanced analytical model for heat transfer in biological tissues, improving thermal therapy precision. The refined bioheat equation offers more realistic simulations for laser treatments.
Area of Science:
- Biomedical Engineering
- Thermal Physics
- Mathematical Modeling
Background:
- The Pennes bioheat equation is standard for tissue heat transfer but lacks analytical solutions.
- Existing models often use classical Fourier heat conduction, neglecting thermal relaxation times.
Purpose of the Study:
- To develop a novel 3D analytical model for heat transfer in biological tissues using MATHEMATICA.
- To refine the Pennes bioheat equation by incorporating non-Fourier heat transfer and localized heating.
- To derive closed-form analytical solutions for both classical and improved bioheat equations.
Main Methods:
- Developed a 3D analytical model in MATHEMATICA.
- Incorporated non-Fourier heat transfer (relaxation time) and Dirac functions.
- Validated the model using COMSOL Multiphysics simulations.
- Derived closed-form analytical solutions for enhanced bioheat equations.
Main Results:
- Achieved a generalized analytical model for bioheat transfer.
- Demonstrated agreement between analytical (MATHEMATICA) and numerical (COMSOL) results.
- Identified an optimal thermal relaxation time of 1.16 s for simulations.
- Investigated thermal exposure times from 0.01 s to 120 s.
Conclusions:
- The developed analytical model provides a more realistic simulation of heat transfer in biological tissues.
- The refined bioheat equation enhances understanding of thermal therapies, particularly laser irradiation.
- This work supports advancements in optimizing laser-based medical treatments and thermal therapies.
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