THE VIABILITY OF SCALED PARTICLE APPROACH FOR N-BODY SIMULATIONS OF MIXED-SIZE HIGHLY-COLLISIONAL PARTICLE SYSTEM IN GASLESS ENVIRONMENT

• Main Author: Rezky, Muhammad
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/68731
• Institution: Institut Teknologi Bandung

Within the process behind the formation of planetary bodies, the dynamical nature of the formation of planetesimals is still not well understood and contains much uncertainty in its theories. Our current understanding of it was built from observational results, which then continues with N-body numerical simulations. But the formation of a planetesimal is already complex, with ~1027 dust particles that interact with each other and its environment. This presents a challenge to simulate a simplified but representative numerical system that achieves the best of both computational accuracy and time optimisation, which lead us to the introduction of the scaled particle approach. Despite the apparent demand and advantages over super-particle approximation, this approach is still understudied and currently applied only to single-size particle populations. This research aimed to review and expand the scaled particle approach on highlycollisional N-body gasless simulations with mixed-size particle populations. As such, this work highlights the conservation of the collision rate on both physical and numerical systems. The general simulation algorithm was built in Python, using the REBOUND code package and integrator IAS15. As for the implementation of the scaled particle approach, the calculation of numerical particle properties was done separately for each particle species, before mixing them into a simulated system. Simulations have been done on both single-sized and mixed-size particle populations, with results indicating that simulated systems which implement the scaled particle approach can emulate the collisional state of the real physical system with a smaller number of particles. This approach will make it possible to simulate a system of heterogeneous particles that was found in PPDs until it produces a concrete product that maintains its representability to the physical systems, much closer to previous simulation attempts, with less computing power.