Finite Element Analysis of Space Debris Removal by High-power Lasers

With the development of space station technologies, irradiation of space debris by space-based high-power lasers, can locally generate high-temperature plasmas and micro momentum, which may achieve the removal of debris through tracking down. Considered typical square-shaped space debris of material Ti with 5cmx5cm size, whose thermal conductivity, density, specific heat capacity and emissivity are 7.62W/(m.degrees C), 4500kg/m(3), 0.52J/(kg.degrees C) and 0.3, respectively, based on the finite element analysis of ANSYS, each irradiation of space debris by high-power lasers with power density 106W/m(2) and weapons-grade lasers with power density 3000W/m(2) are simulated under space environment, and the temperature curves due to laser thermal irradiation are obtained and compared. Results show only 2s is needed for high-power lasers to make the debris temperature reach to about 10000K, which is the threshold temperature for plasmas-state conversion. While for weapons-grade lasers, it is 13min needed. Using two line elements (TLE), and combined with the coordinate transformation from celestial coordinate system to site coordinate system, the visible period of space debris is calculated as 5-10min. That is, in order to remove space debris by laser plasmas, the laser power density should be further improved. The article provides an intuitive and visual feasibility analysis method of space debris removal, and the debris material and shape, laser power density and spot characteristics are adjustable. This finite element analysis method is low-cost, repeatable and adaptable, which has an engineering-prospective applications.