Thermal analysis and optimization of ytterbium doped double clad fiber laser based on a general analytic method

摘要

300W end-pump power deposited as heat is predicted to cause a thermal damage for doped double clad fiber (DDCF). In order to estimate cooling effects of DDCF through radiator, the general equation has been solved with a thermal convection boundary under a rectangular plate at the periphery. Steady-state thermal profiles are developed using both a full numerical solution and an analytic approximation which assume the total heat of fiber dissipating through the radiator. The analytic solution, which is in good agreement with the numerical solution, is utilized to obtain a visual result for fiber cooling characteristic. By changing the arrangement of active optical fiber on the radiator base plate, the maximum temperature of the substrate surface is reduced. The data of the two methods show that the cooling effect of optic fiber laser is related to the way of optical fiber and interface materials placement on the radiator. The cooling effect is better when the first kind of layout with a high thermal conductivity interface material layer between optical fiber and the radiator.