双包层光纤激光器最大输出功率的估算

Estimation of maximum output power of double clad fiber laser

通过热传导方程和边界条件得到高功率双包层光纤激光器温度分布的简化解析解,利用AN-SYS模拟验证了简化的合理性,并以双包层的掺镱光纤激光器为例,把外包层的临界温度设定为80℃,计算了光纤激光器在自然对流、风扇制冷和水制冷条件下最大输出功率。计算结果表明:自然对流的情况下,对流传热系数为10 W.m-2.K-1时,光纤激光器的最大输出功率为105 W;风扇制冷的情况下,对流传热系数为80W.m-2.K-1时,光纤激光器的最大输出功率820 W;要达到kW以上功率输出,必须对光纤进行主动水冷。

Temperature distribution in high power fiber laser was approximately analyzed by thermal conductive equation and boundary condition. The rationality of numerical solution was validated by ANSYS simulation. The fiber laser coating＇s critical temperature was set 80 ℃ and the maximum output power using the thermal conductive equation was computed when the fiber laser is cooled by fan or water, such as Yb-doped double clad fiber laser. Results indicate that when the fiber is cooled in air （the heat transfer coefficient is 10 W·m^-2·K^-1）, fiber laser＇s maximum output power is 105 W. When the fiber is cooled by fan （the heat transfer coefficient is 80 W ·m^-2·K^-1）, the maximum output power is 820 W. If the output power is demanded above 1 kW, the fiber laser must be cooled by water.