MaThRad Workshop 2: Reactor Physics Workshop
Part of the Jacobs/ANSWERS Seminar 2023
18 – 19 May 2023
The MaThRad team were delighted contribute to the 2023 ANSWERS Seminar – an annual meeting for ANSWERS customers and staff associated with the development and use of ANSWERS software. MaThRad hosted two days of workshops which focussed on the numerical methods used by ANSWERS, beginning with introductions on the Monte Carlo software tools MONK (Jacobs), and SCONE (Cambridge) and then concentrating on three main topics:
Convergence and Acceleration of Fission Source Simulations
One of the most important calculations in reactor physics is determining when a reactor is critical, subcritical, or supercritical. Mathematically, the computation amounts to solving an eigenvalue problem: eigenvalue k = 1 corresponds to criticality, k < 1 to subcriticality, and k > 1 to supercriticality. In order to compute the eigenvalue, it is crucial to first calculate the so-called fission source distribution, often denoted by S, which describes the long-run average distribution of fission events in the reactor. Click here to read more…
There are two broad paradigms in numerical analysis: the deterministic approach where space and/or time are discretised in order to approximate a dynamical system, and the Monte Carlo approach where the behaviour of the system is studied by simulating many random replicates of its evolution. The random ray method is a hybrid approach that seeks to leverage the advantages of both paradigms. Click here to read more…
Monte Carlo simulations usually rely on simulating a large number of particles in parallel. In nuclear simulations, the number of particles has to be controlled, so that the system does not die out or grow beyond the limits of computer memory. This population control has the unintended consequence of “clustering” particles in specific spatial regions as the simulation progresses. In turn, clustering renders calculations based on simulation output unreliable. Click here to read more…
Programme and Presentations
Thursday 18th May
(Click on the Session titles to download the presentations where available)
| Session | Presenter | Institution\Company |
| Overview of SCONE | Mikolaj Kowalski | University of Cambridge |
| Overview of MONK | Simon Richards | Jacobs |
| Fission Source Convergence | ||
| Fission Source Convergence | Paul Smith | Jacobs |
| Monte Carlo Source Convergence Acceleration | Valeria Raffuzzi | University of Cambridge |
| Exact methods for simulating stationary distributions | Alex Cox | University of Bath |
| Sequential Monte Carlo: Some perspectives from outside neutron transport | Adam Johansen | University of Warwick |
| Breakout Session: Discussion on Fission Source Convergence | ||
| Breakout Session: Fission Source Convergence Potential Research Topics | ||
| The Random Ray Method | ||
| Monte Carlo “On Rails” The Random Ray Method of Neutron Transport | John Tramm | Argonne National Laboratory |
| Breakout Session: Discussion on the Random Ray Method | ||
| The Random Ray Method: Potential Research Topics | ||
Friday 19th May:
| Session | Presenter | Institution\Company |
| Clustering | ||
| Neutron clustering: from the gambler’s ruin to reactor physics | Eric Dumonteil | CEA – Fundamental Research Division |
| Clustering in particle systems of fixed size | Oliver Tough | University of Bath |
| Breakout Session: Discussion on Clustering | ||
| Clustering: Potential Research Topics | ||
| Markov Media for Radiation Transport | Mikolaj Kowalski | University of Cambridge |
