中文摘要：

磁流体在肿瘤中的扩散和能量在肿瘤中的传递是磁流体热疗中的关键过程，并直接影响到治疗的效果。本文针对这些关键过程，建立了靶区内球形肿瘤的多物理场耦合模型，并采用有限元方法，对其进行了数值求解，获得了肿瘤靶区组织的压力分布、温度分布及磁流体浓度分布。分析了扩散时间、注射点以及磁流体比吸收率等关键因素对温度分布的影响。结果表明，延长扩散时间、在注射总量一定的情况下增加注射点数及增大比吸收率，均可使肿瘤中达到细胞坏死温度的体积增大，从而提高肿瘤的治愈率。但增大比吸收率的同时也会使正常组织的温升增加。

英文摘要：

Diffusion of magnetic fluid and energy transport in the tumor are crucial processes for magnetic fluid hyperthermia and play an important role in tumor treatment. A coupled numerical simulation, including a fluid transport model, a solute transport model and a heat transfer model, was developed to investigate the diffusion process of magnetic fluid and the temperature rise in the tumor tissue in alternating magnetic field. The finite element method was applied to the calculations, and the pressure distribution, concentration distribution, and temperature distribution were obtained. Moreover, the effects of the diffusion time of the magnetic fluid, the number of injection points and the specific absorption rate （SAR） on temperature distributions were analyzed. The results showed that the increases of the diffusion time and the number of injection points caused the volume of tumor tissues with the desired necrosis temperature to increase, and decrease the highest heating temperature of the tumor tissue as well. An increase in the SAR always resulted in an obvious increase in the volume of tumor tissues with the desired necrosis temperature. However, the temperature of the normal tissue also increased with the increase of SAR, which might cause dangers in clinical treatments when it was higher than the safety temperature.