Abstract To address the thermal effect of 3000 W Yb-doped double-clad fiber (YDCF), a double-layer substrate is designed to encapsulate a high power fiber laser. A thermal resistance model is proposed where the contact between the layers is ideal, and the thermal conductivity and thickness, as well as the position of the additional layer, are considered. The axial temperature of the fiber is the lowest, and the temperature uniformity the best, in an Hm-Al system. In addition, the thermal resistance model is also established where the contact between the layers is nonideal. The influence of the interfacial heat transfer coefficient and the thickness of the isotropic and orthotropic layers on the temperature distribution of the fiber are considered. The average temperature of the fiber is the lowest, and the temperature uniformity the best, in an Iso-Ortho system. Numerical simulations are used to verify the two thermal resistance models. The results show that the trend of the change in the analytical value is consistent with that of the simulation value. These thermal resistance models are reasonable and accurate and can be used to analyze more complex fiber laser packaging structures.

中文翻译：

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掺镱双包层光纤在复合系统中的散热模型及温度分布

摘要 为解决3000 W掺镱双包层光纤（YDCF）的热效应问题，设计了双层基板封装高功率光纤激光器。提出了一种热阻模型，其中层之间的接触是理想的，并且考虑了热导率和厚度，以及附加层的位置。在Hm-Al体系中，纤维的轴向温度最低，温度均匀性最好。此外，还建立了层间接触不理想的热阻模型。考虑了界面传热系数和各向同性层和各向异性层的厚度对纤维温度分布的影响。纤维平均温度最低，温度均匀性最好，在 Iso-Ortho 系统中。数值模拟用于验证两种热阻模型。结果表明，分析值的变化趋势与模拟值的变化趋势一致。这些热阻模型合理且准确，可用于分析更复杂的光纤激光器封装结构。