Weighted-Delta-Tracking for Monte Carlo Particle Transport

Weighted-Delta-Tracking for Monte Carlo Particle Transport

Weighted-Delta-Tracking for Monte Carlo Particle Transport 150 150 UKAEA Opendata
CCFE-PR(15)54

Weighted-Delta-Tracking for Monte Carlo Particle Transport

Monte Carlo particle transport (MCPT) codes are incredibly powerful and versatile tools to simulate particle behavior in a multitude of scenarios, such as core/criticality studies, radiation protection, shielding, medicine and fusion research to name just a small subset applications. However, MCPT codes can be very computationally expensive to run when the model geometry contains large attenuation depths and/or contains many components. This paper proposes a simple modification to the Woodcock tracking method used by some Monte Carlo particle transport codes. The Woodcock method utilises the rejection method for sampling virtual collisions as a method to remove collision distance sampling at material boundaries. However, it suffers from poor computational efficiency when the sample acceptance rate is low. The proposed method removes rejection sampling from the Woodcock method in favor of a statistical weighting scheme, which improves the computational efficiency of a Monte Carlo particle tracking code. It is shown that the modified Woodcock method is less computationally expensive than standard ray-tracing and rejection-based Woodcock tracking methods and achieves a lower variance, given a specified accuracy.

Collection:
Journals
Journal:
Annals of Nuclear Energy
Publisher:
Elsevier
Published date:
11/01/2015