Trajectory and survivability estimation of reentry space debris

KAIST researchers have developed trajectory and survivability estimation program for reentry space debris, which can consider the effects of high- temperature gas dynamics and separation behavior, has been developed.

Article  |  Fall 2019

The rapid increase in the amount of space debris is becoming a threat to space assets and to Earth. The debris eventually reenters the Earth’s atmosphere because the lifetime of the debris is limited due to perturbations such as atmospheric drag and solar radiation pressure. During reentry, debris exposed to high temperature temperatures behind a shock wave and undergoes ablation, breakup, and thermochemical non-equilibrium phenomena.

To date, several reentry trajectory and survivability estimation programs have been developed, with examples including a spacecraft-oriented code like Spacecraft Atmospheric Reentry and Aerothermal Breakup (SCARAB) and an object-oriented code like Object Reentry Survival Analysis Tool (ORSAT). These codes are not open to the public. There are a few open codes such as Debris Assessment Software (DAS) and Debris Risk Assessment and Mitigation Analysis (DRAMA), but they have several limitations compared to ORSAT and SCARAB, implying a self-development is required. Furthermore, the existing codes seem to not have the capability to predict the phenomena such as non-equilibrium surface heat transfer and breakup including separation behavior.

In light of this, Seong-Hyeon Park (postdoc fellow) and Gisu Park (assistant professor) in the Department of Aerospace Engineering at KAIST developed a trajectory and survivability estimation program for reentry space debris, which can consider the effects of high-temperature gas dynamics and separation behavior. One of their major research findings is that, as the catalytic efficiency increases, the heat transfer rate increases, leading to low space debris survivability. This implies the importance of the non-equilibrium surface heat transfer in the development of a reentry trajectory estimation program.