Analysis of thermal management strategies for packaging high power fiber optic waveguides

Abstract

High power fiber optic waveguides are emerging as a critical component in high energy laser systems, optical relay of electrical power, and optoelectronic devices. To make use of the advantages of higher power density in these systems, a thorough understanding of the heat dissipation characteristics and thermal management strategies must be developed. With this aim in mind, we report a parametric multi-physics analysis to guide in the materials selection and design of thermal management strategies that would enable operation at previously unobtainable powers and wavelengths. We offer practical design considerations for packaging materials, heat sink design, and containment geometries, and offer insights into how to increase thermally limited power output beyond commercially available state of the art strategies. The results of this parametric analysis suggest that substrate/containment material thermal conductivity should exceed 100 Wm-1K-1, and that under that condition, both heat sink cooling strategy and filler thermal conductivity substantially affect peak temperature. High filler thermal conductivity and high heat sink convective coefficient are required to the point that cutting-edge strategies for conductivity and convective enhancements may be required to allow operation under the desired parameters.