In this article, we propose a numerical analysis of the effect of the orthotropic tensor of thermal conductivity during microwave heating of a heterogeneous core–shell morphology. The core is made of a material with high thermal conductivity, whose dielectric loss coefficient guarantees high microwave energy to heat conversion. This type of morphology has a high potential for use in the ablation of tumors, chemotherapy, drug release, and enhancing nano-catalysis, among other applications. Nonetheless, the effect of orthotropic thermal conductivity has not been extensively studied. The system under analysis is a core surrounded by two shells, which are made of materials whose thermal conductivities vary orthogonally. The thermal model consists of a system of three time-dependent coupled parabolic partial differential equations. Such a model is numerically solved using finite elements, and assuming a thermal conductivity tensor for each layer. A strong effect of this type of anisotropy was observed on temperature profiles compared to traditional isotropic materials. Besides, the symmetric release of its internally generated energy was seriously affected. Selected simulated experimental scenarios are presented.

中文翻译：

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核-壳球系统微波热处理过程中正交各向异性热导率张量的影响分析

在本文中，我们提出了对异质核壳形态的微波加热过程中热导率正交各向异性张量的影响的数值分析。磁芯由高导热材料制成，其介电损耗系数保证了较高的微波能量热转换。这种类型的形态在肿瘤消融、化疗、药物释放和增强纳米催化等应用中具有很高的潜力。尽管如此，正交各向异性热导率的影响尚未得到广泛研究。所分析的系统是一个由两个壳包围的核心，壳由热导率正交变化的材料制成。热模型由三个瞬态耦合抛物线偏微分方程系统组成。这种模型使用有限元进行数值求解，并假设每一层的热导率张量。与传统的各向同性材料相比，这种类型的各向异性对温度曲线的影响很大。此外，其内部产生的能量的对称释放受到严重影响。介绍了选定的模拟实验场景。