Dr Andrew Buchan

Senior Lecturer in Engineering Science

School of Engineering and Materials Science
Queen Mary University of London

a.buchan@qmul.ac.uk

www.sems.qmul.ac.uk/staff/a.buchan/

Centre for Sustainable Engineering
Centre for Intelligent Transport

Research
Publications
Grants

Research

Computational Physics, Reactor Physics, Finite Elements

Interests

I specialise in developing computational methods for multi-physics modelling of radiation, fluid flow, and heat transfer, with applications in nuclear engineering, environmental flows, pollution dispersion, ultraviolet-C light for disease removal in air, and chemical removal in drinking water. I have over 20 years of research experience in developing numerical methods, spanning finite elements, control volume, adaptive resolution, Krylov solvers, multi-grid, reduced-order models, sub-grid models, sensitivity analysis, uncertainty quantification, and AI-based modelling. I have developed several frameworks, including FETCH and FETCH2, which are multi-physics codes for nuclear modelling based at Imperial College London, and Wyvern, a coupled radiation-fluid flow simulator for assessing ultraviolet light inactivation of diseases in air and water. I have secured over £8 million in research funding, including an EPSRC early career research fellowship.

Publications

Publications of specific relevance to the Centre for Sustainable Engineering

2024

A reduced order model discretisation of the space-angle phase-space dimensions of the Boltzmann transport equation with application to nuclear reactor problems
Buchan AG, Navon IM and Yang L
Journal of Computational Physics, Elsevier vol. 517, 113268-113268.

DOI 10.1016/j.jcp.2024.113268

QMRO

10-07-2024

2023

Computational Modelling in Nuclear Science and Engineering: The Role of Artificial Intelligence
Pain C, Tehrani A, Heaney C, Chen B, Nwegbu K, Phillips T, Jones A, Dargaville S, Buchan A, Smith P, Bankhead M and Cacuci D
Nuclear Future vol. 19 (5), 42-50.
01-09-2023

Solving the Discretised Neutron Diffusion Equations using Neural Networks
toby P, heaney C, Chen B, Buchan A and Pain C
International Journal For Numerical Methods in Engineering, Wiley

DOI 10.1002/nme.7321

QMRO

12-07-2023

2022

Authors reply to comment by Michio Aoyama on “Development of a gamma ray dose rate calculation and mapping tool for Lagrangian marine nuclear emergency response models” by Little et al.
Little A, Piggott MD and Buchan AG
Marine Pollution Bulletin, Elsevier vol. 184

DOI 10.1016/j.marpolbul.2022.114150

QMRO

10-10-2022

An adaptive reduced order model for the angular discretization of the Boltzmann transport equation using independent basis sets over a partitioning of the space-angle domain
Hughes AC and Buchan AG
International Journal For Numerical Methods in Engineering vol. 123 (16), 3781-3799.

DOI 10.1002/nme.6989

QMRO

30-08-2022

Optimised Adjoint Sensitivity Analysis Using Adjoint Guided Mesh Adaptivity Applied to Neutron Detector Response Calculations
Buchan AG, Cacuci DG, Dargaville S and Pain CC
Energies, Mdpi vol. 15 (14), 5102-5102.

DOI 10.3390/en15145102

QMRO

13-07-2022

Development of a gamma ray dose rate calculation and mapping tool for Lagrangian marine nuclear emergency response models
Little A, Piggott MD and Buchan AG
Marine Pollution Bulletin, Elsevier vol. 181

DOI 10.1016/j.marpolbul.2022.113895

QMRO

08-07-2022

Inactivation Rates for Airborne Human Coronavirus by Low Doses of 222 nm Far-UVC Radiation
Welch D, Buonanno M, Buchan AG, Yang L, Atkinson KD, Shuryak I and Brenner DJ
Viruses, Mdpi vol. 14 (4)

DOI 10.3390/v14040684

QMRO

25-03-2022

2021

Improved estimates of 222 nm far-UVC susceptibility for aerosolized human coronavirus via a validated high-fidelity coupled radiation-CFD code
Buchan AG, Yang L, Welch D, Brenner DJ and Atkinson KD
Scientific Reports, Springer Nature vol. 11 (1)

DOI 10.1038/s41598-021-99204-0

QMRO

07-10-2021

Reduced-order modelling applied to the multigroup neutron diffusion equation using a nonlinear interpolation method for control-rod movement
Heaney CE, Buchan AG, Pain CC and Jewer S
Energies vol. 14 (5)

DOI 10.3390/en14051350

QMRO

01-03-2021

A comparison of element agglomeration algorithms for unstructured geometric multigrid
Dargaville S, Buchan AG, Smedley-Stevenson RP, Smith PN and Pain CC
Journal of Computational and Applied Mathematics, Elsevier vol. 390

DOI 10.1016/j.cam.2020.113379

QMRO

12-01-2021

2020

Predicting airborne coronavirus inactivation by far-UVC in populated rooms using a high-fidelity coupled radiation-CFD model
Buchan AG, Yang L and Atkinson KD
Scientific Reports, Springer Nature vol. 10 (1)

DOI 10.1038/s41598-020-76597-y

QMRO

12-11-2020

A discontinuous and adaptive reduced order model for the angular discretization of the Boltzmann transport equation
Hughes AC and Buchan AG
International Journal For Numerical Methods in Engineering, Wiley vol. 121 (24), 5647-5666.

DOI 10.1002/nme.6516

QMRO

20-09-2020

A three-phase interpenetrating continua approach for wave and porous structure interaction
Yang L, Buchan A, Pavlidis D, Jones A, Smith P, Sakai M and Pain C
Engineering Computations, Emerald Publishing Limited.

DOI 10.1108/EC-08-2019-0386

QMRO

14-05-2020

2019

Scalable angular adaptivity for Boltzmann transport
Dargaville S, Buchan AG, Smedley-Stevenson RP, Smith PN and Pain CC
Journal of Computational Physics, Elsevier Bv, 109124-109124.

DOI 10.1016/j.jcp.2019.109124

QMRO

20-11-2019

Angular adaptivity with spherical harmonics for Boltzmann transport
Dargaville S, Buchan AG, Smedley-Stevenson RP, Smith PN and Pain CC
Journal of Computational Physics, Elsevier Bv vol. 397, 108846-108846.

DOI 10.1016/j.jcp.2019.07.044

QMRO

31-07-2019

A combined immersed body and adaptive mesh method for simulating neutron transport within complex structures
Buchan AG, Dargaville S and Pain CC
Annals of Nuclear Energy, Elsevier Bv vol. 134, 88-100.

DOI 10.1016/j.anucene.2019.05.044

QMRO

11-06-2019

An angular reduced order model for radiative transfer in non grey media
BUCHAN AG
Journal of Quantitative Spectroscopy and Radiative Transfer, Elsevier

DOI 10.1016/j.jqsrt.2019.03.005

QMRO

09-03-2019

Scalable angular adaptivity and robust error metrics
Dargaville S, Buchan AGB, Smedley-Stevenson RP, Smith PN and Pain CC
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering, M and C 2019., 52-60.
01-01-2019

A Reduced Order Model for the Fast Predictions of Reactivity and Neutron Distributions within Reactor Cores
Buchan A, Jewer S and Navon IM
International Conference On Computational & Experimental Engineering and Sciences, Tech Science Press vol. 22 (4), 179-179.

DOI 10.32604/icces.2019.05396

01-01-2019

Angular adaptivity with filtered Pn methods
Dargaville S, Buchan AG, Smedley-Stevenson RP, Smith PN and Pain CC
Transactions of the American Nuclear Society. vol. 120, 479-482.
01-01-2019

Adaptive Modelling for Multiphase Flow Through Debris Bed With Boiling
Yang L, Buchan A, Jones A, Smith P, Sakai M and Pain C
International Conference On Computational & Experimental Engineering and Sciences, Tech Science Press vol. 22 (1), 95-95.

DOI 10.32604/icces.2019.05077

01-01-2019

2018

A Haar Wavelet Method for Angularly Discretising the Boltzmann Transport Equation
Adigun BJ, BUCHAN AG, Adam A, Dargaville S, Goffin MA and Pain CC
Progress in Nuclear Energy, Elsevier

DOI 10.1016/j.pnucene.2018.05.023

QMRO

13-06-2018

Reactor simulators and reduced order modeling
Heaney CE, Pain CC, Buchan AG and Jewer S
Nuclear Future vol. 14 (3), 49-54.
01-01-2018

2017

A goal-based angular adaptivity method for thermal radiation modelling in non grey media
Soucasse L, Dargaville S, Buchan AG and Pain CC
Journal of Quantitative Spectroscopy and Radiative Transfer vol. 200, 215-224.

DOI 10.1016/j.jqsrt.2017.06.015

QMRO

19-06-2017

Adaptive angle and parallel multigrid for deterministic shielding problems
Dargaville S, Buchan A, Smedley-Stevenson R, Smith P and Pain C
Epj Web of Conferences, Edp Sciences vol. 153

DOI 10.1051/epjconf/201715306026

QMRO

01-01-2017

2016

An efficient space-angle subgrid scale discretisation of the neutron transport equation
Buchan AG and Pain CC
Annals of Nuclear Energy, Elsevier vol. 94, 440-450.

DOI 10.1016/j.anucene.2016.03.012

01-08-2016

2015

Solving the Boltzmann transport equation with multigrid and adaptive space/angle discretisations
Dargaville S, Goffin MA, Buchan AG, Pain CC, Smedley-Stevenson RP, Smith PN and Gorman G
Annals of Nuclear Energy, Elsevier vol. 86, 99-107.

DOI 10.1016/j.anucene.2015.02.014

01-12-2015

Adaptive Haar wavelets for the angular discretisation of spectral wave models
Adam A, Buchan AG, Piggott MD, Pain CC, Hill J and Goffin MA
Journal of Computational Physics vol. 305, 521-538.

DOI 10.1016/j.jcp.2015.10.046

QMRO

02-11-2015

Non-intrusive reduced order modelling of the Navier–Stokes equations
Xiao D, Fang F, Buchan AG, Pain CC, Navon IM and Muggeridge A
Computer Methods in Applied Mechanics and Engineering vol. 293, 522-541.

DOI 10.1016/j.cma.2015.05.015

QMRO

28-05-2015

A POD reduced order model for resolving angular direction in neutron/photon transport problems
Buchan AG, Calloo AA, Goffin MG, Dargaville S, Fang F, Pain CC and Navon IM
Journal of Computational Physics vol. 296, 138-157.

DOI 10.1016/j.jcp.2015.04.043

QMRO

04-05-2015

2014

Goal-based angular adaptivity applied to a wavelet-based discretisation of the neutral particle transport equation
Goffin MA, Buchan AG, Dargaville S, Pain CC, Smith PN and Smedley-Stevenson RP
Journal of Computational Physics vol. 281, 1032-1062.

DOI 10.1016/j.jcp.2014.10.063

QMRO

06-11-2014

Reduced order modelling of an unstructured mesh air pollution model and application in 2D/3D urban street canyons
Fang F, Zhang T, Pavlidis D, Pain CC, Buchan AG and Navon IM
Atmospheric Environment, Elsevier vol. 96, 96-106.

DOI 10.1016/j.atmosenv.2014.07.021

01-10-2014

Adjoint eigenvalue correction for elliptic and hyperbolic neutron transport problems
Merton SR, Smedley-Stevenson RP, Pain CC and Buchan AG
Progress in Nuclear Energy, Elsevier vol. 76, 1-16.

DOI 10.1016/j.pnucene.2014.04.014

01-09-2014

Goal-based angular adaptivity applied to the spherical harmonics discretisation of the neutral particle transport equation
Goffin MA, Buchan AG, Belme AC, Pain CC, Eaton MD, Smith PN and Smedley-Stevenson RP
Annals of Nuclear Energy, Elsevier vol. 71, 60-80.

DOI 10.1016/j.anucene.2014.03.030

01-09-2014

An immersed body method for coupled neutron transport and thermal hydraulic simulations of PWR assemblies
Jewer S, Buchan AG, Pain CC and Cacuci DG
Annals of Nuclear Energy, Elsevier vol. 68, 124-135.

DOI 10.1016/j.anucene.2013.12.018

01-06-2014

Non-linear model reduction for the Navier–Stokes equations using residual DEIM method
Xiao D, Fang F, Buchan AG, Pain CC, Navon IM, Du J and Hu G
Journal of Computational Physics, Elsevier vol. 263, 1-18.

DOI 10.1016/j.jcp.2014.01.011

QMRO

01-04-2014

Reduced order borehole induction modelling
Ardjmandpour N, Pain CC, Fang F, Buchan AG, Singer J, Player MA, Xu X, Navon IM and Carter J
International Journal of Computational Fluid Dynamics, Taylor & Francis vol. 28 (3-4), 140-157.

DOI 10.1080/10618562.2014.923846

16-03-2014

The immersed body supermeshing method for modelling reactor physics problems with complex internal structures
Buchan AG, Farrell PE, Gorman GJ, Goddard AJH, Eaton MD, Nygaard ET, Angelo PL, Smedley-Stevenson RP, Merton SR and Smith PN
Annals of Nuclear Energy, Elsevier vol. 63, 399-408.

DOI 10.1016/j.anucene.2013.07.044

01-01-2014

2013

A POD reduced‐order model for eigenvalue problems with application to reactor physics
Buchan AG, Pain CC, Fang F and Navon IM
International Journal For Numerical Methods in Engineering, Wiley vol. 95 (12), 1011-1032.

DOI 10.1002/nme.4533

03-07-2013

Minimising the error in eigenvalue calculations involving the Boltzmann transport equation using goal-based adaptivity on unstructured meshes
Goffin MA, Baker CMJ, Buchan AG, Pain CC, Eaton MD and Smith PN
Journal of Computational Physics, Elsevier vol. 242, 726-752.

DOI 10.1016/j.jcp.2012.12.035

01-06-2013

Goal based mesh adaptivity for fixed source radiation transport calculations
Baker CMJ, Buchan AG, Pain CC, Tollit BS, Goffin MA, Merton SR and Warner P
Annals of Nuclear Energy, Elsevier vol. 55, 169-183.

DOI 10.1016/j.anucene.2012.11.029

01-05-2013

An adjoint-based method for improving computational estimates of a functional obtained from the solution of the Boltzmann Transport Equation
Merton SR, Buchan AG, Pain CC and Smedley-Stevenson RP
Annals of Nuclear Energy, Elsevier vol. 54, 1-10.

DOI 10.1016/j.anucene.2012.10.031

01-04-2013

Multimesh anisotropic adaptivity for the Boltzmann transport equation
Baker CMJ, Buchan AG, Pain CC, Farrell PE, Eaton MD and Warner P
Annals of Nuclear Energy, Elsevier vol. 53, 411-426.

DOI 10.1016/j.anucene.2012.07.023

01-03-2013

Simulated spatially dependent transient kinetics analysis of the Oak Ridge Y12 plant criticality excursion
Buchan AG, Pain CC, Tollit BS, Gomes JLMA, Eaton MD, Gorman GJ, Cooling CM, Goddard AJH, Nygaard ET, Angelo PL and Smith PN
Progress in Nuclear Energy, Elsevier vol. 63, 12-21.

DOI 10.1016/j.pnucene.2012.09.006

01-03-2013

Non-linear Petrov–Galerkin methods for reduced order modelling of the Navier–Stokes equations using a mixed finite element pair
Xiao D, Fang F, Du J, Pain CC, Navon IM, Buchan AG, ElSheikh AH and Hu G
Computer Methods in Applied Mechanics and Engineering, Elsevier vol. 255, 147-157.

DOI 10.1016/j.cma.2012.11.002

01-03-2013

2012

Simulated transient dynamics and heat transfer characteristics of the water boiler nuclear reactor – SUPO – with cooling coil heat extraction
Buchan AG, Pain CC, Goddard AJH, Eaton MD, Gomes JLMA, Gorman GJ, Cooling CM, Tollit BS, Nygaard ET, Glenn DE and Angelo PL
Annals of Nuclear Energy, Elsevier vol. 48, 68-83.

DOI 10.1016/j.anucene.2012.03.027

01-10-2012

Quadratic inner element subgrid scale discretisation of the Boltzmann transport equation
Baker CMJ, Buchan AG, Pain CC, Tollit B, Eaton MD and Warner P
Annals of Nuclear Energy, Elsevier vol. 45, 124-137.

DOI 10.1016/j.anucene.2012.02.020

01-07-2012

A sub‐grid scale finite element agglomeration multigrid method with application to the Boltzmann transport equation
Buchan AG, Pain CC, Umpleby AP and Smedley‐Stevenson RP
International Journal For Numerical Methods in Engineering, Wiley vol. 92 (3), 318-342.

DOI 10.1002/nme.4350

12-06-2012

2011

Riemann boundary conditions for the Boltzmann transport equation using arbitrary angular approximations
Buchan AG, Merton SR, Pain CC and Smedley-Stevenson RP
Annals of Nuclear Energy, Elsevier vol. 38 (5), 1186-1195.

DOI 10.1016/j.anucene.2010.11.019

01-05-2011

2010

The Inner-Element Subgrid Scale Finite Element Method for the Boltzmann Transport Equation
Buchan AG, Candy AS, Merton SR, Pain CC, Hadi JI, Eaton MD, Goddard AJH, Smedley-Stevenson RP and Pearce GJ
Nuclear Science and Engineering, Taylor & Francis vol. 164 (2), 105-121.

DOI 10.13182/nse08-82

01-02-2010

2008

Optimal discontinuous finite element methods for the Boltzmann transport equation with arbitrary discretisation in angle
Merton SR, Pain CC, Smedley-Stevenson RP, Buchan AG and Eaton MD
Annals of Nuclear Energy, Elsevier vol. 35 (9), 1741-1759.

DOI 10.1016/j.anucene.2008.01.023

01-09-2008

Linear and Quadratic Hexahedral Wavelets on the Sphere for Angular Discretizations of the Boltzmann Transport Equation
Buchan AG, Pain CC, Eaton MD, Goddard AJH and Smedley-Stevenson RP
Nuclear Science and Engineering, Taylor & Francis vol. 159 (2), 127-152.

DOI 10.13182/nse159-127

01-06-2008

Chebyshev spectral hexahedral wavelets on the sphere for angular discretisations of the Boltzmann transport equation
Buchan AG, Pain CC, Eaton MD, Smedley-Stevenson RP and Goddard AJH
Annals of Nuclear Energy, Elsevier vol. 35 (6), 1098-1108.

DOI 10.1016/j.anucene.2007.08.021

01-06-2008

Self-Adaptive Spherical Wavelets for Angular Discretizations of the Boltzmann Transport Equation
Buchan AG, Pain CC, Eaton MD, Smedley-Stevenson RP and Goddard AJH
Nuclear Science and Engineering, Taylor & Francis vol. 158 (3), 244-263.

DOI 10.13182/nse08-a2751

01-03-2008

2005

Linear and quadratic octahedral wavelets on the sphere for angular discretisations of the Boltzmann transport equation
Buchan AG, Pain CC, Eaton MD, Smedley-Stevenson RP and Goddard AJH
Annals of Nuclear Energy, Elsevier vol. 32 (11), 1224-1273.

DOI 10.1016/j.anucene.2005.01.005

01-07-2005

Grants of specific relevance to the Centre for Sustainable Engineering

Parallel solvers for voxel-dominant meshes for the Boltzmann Transport Equation
Andrew Buchan
£10,000 Science & Technology Research Council (STFC)
01-11-2024 - 31-03-2025

Fukushima ALPS water A modelling framework for predicting tritium dispersion released within the marine environment
Andrew Buchan
£20,000 EPSRC Engineering and Physical Sciences Research Council
01-10-2023 - 29-02-2024

Early Career Fellowship-GRANT TRANSFER
Andrew Buchan
£464,161 EPSRC Engineering and Physical Sciences Research Council
19-06-2017 - 18-12-2022