GPU-enabled N-body simulations of the Solar System using a VOVS Adams integrator

• Published in: Journal of computational science Vol. 16; pp. 89 - 97
• Main Authors: Sharp, P.W., Newman, W.I.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-09-2016
• Subjects: Adams method; Collisionless N-body; GPU; Self-gravitating disc; Variable-stepsize; Adams method; Collisionless N-body; GPU; Self-gravitating disc; Variable-stepsize
• ISSN: 1877-7503; 1877-7511
• DOI: 10.1016/j.jocs.2016.04.003

•We present a new optimised CUDA C kernel for N-body gravitational simulations.•We combine the kernel with a variable-stepsize Adams integrator to give speed-ups of over 20.•We use ten simulations of 20 million years to investigate the performance of the program.•We show that the numerical solution is several orders of magnitude more accurate that typically produced with symplectic methods.
Collisionless N-body simulations over tens of millions of years are an important tool in understanding the early evolution of planetary systems. We first present a CUDA kernel for evaluating the gravitational acceleration of N bodies that is intended primarily for when N is less than several thousand. We then use the kernel with a variable-order, variable-stepsize Adams method to perform long, collisionless simulations of the Solar System near limiting precision. The varying stepsize means no special scheme is required to integrate close encounters, and the motion of bodies on eccentric orbits or close to the Sun is calculated accurately. Our method is significantly more accurate than symplectic methods and sufficiently fast.