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Jonathan Trevelyan's Outputs (107)

An extended isogeometric boundary element formulation for three-dimensional linear elastic fracture mechanics (2024)
Journal Article
Rocha, M., Trevelyan, J., & Leonel, E. D. (2024). An extended isogeometric boundary element formulation for three-dimensional linear elastic fracture mechanics. Computer Methods in Applied Mechanics and Engineering, 423, Article 116872. https://doi.org/10.1016/j.cma.2024.116872

This paper presents a novel extended isogeometric boundary element formulation (XIGABEM) for three-dimensional linear elastic fracture mechanics. The formulation utilises the Dual BEM to accommodate coincident geometries for opposin... Read More about An extended isogeometric boundary element formulation for three-dimensional linear elastic fracture mechanics.

3D isogeometric indirect BEM solution based on virtual surface sources on the boundaries of Helmholtz acoustic problems (2024)
Journal Article
Shaaban, A. M., Trevelyan, J., & Rabczuk, T. (2024). 3D isogeometric indirect BEM solution based on virtual surface sources on the boundaries of Helmholtz acoustic problems. Engineering with Computers, 40(4), 2681-2702. https://doi.org/10.1007/s00366-023-01933-5

A solution for 3D Helmholtz acoustic problems is introduced based on an indirect boundary element method (indirect BEM) coupled with isogeometric analysis (IGA). The novelty of this work arises from using virtual surface sources placed directly on th... Read More about 3D isogeometric indirect BEM solution based on virtual surface sources on the boundaries of Helmholtz acoustic problems.

Direct evaluation of stress intensity factors and T-stress for bimaterial interface cracks using the extended isogeometric boundary element method (2023)
Journal Article
Andrade, H., Trevelyan, J., & Leonel, E. (2023). Direct evaluation of stress intensity factors and T-stress for bimaterial interface cracks using the extended isogeometric boundary element method. Theoretical and Applied Fracture Mechanics, 127, Article 104091. https://doi.org/10.1016/j.tafmec.2023.104091

This paper presents a new extended isogeometric boundary element method (XIGABEM) for the analysis of cracks in two-dimensional bimaterial interfaces. The classical NURBS approximations used in isogeometric formulations are augmented with functions b... Read More about Direct evaluation of stress intensity factors and T-stress for bimaterial interface cracks using the extended isogeometric boundary element method.

The solution of the wave-diffusion equation by a Caputo derivative-based Finite Element Method formulation (2023)
Journal Article
Correa, R., Carrer, J., Solheid, B., Trevelyan, J., Arndt, M., & Machado, R. (2023). The solution of the wave-diffusion equation by a Caputo derivative-based Finite Element Method formulation. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 45(5), Article 261. https://doi.org/10.1007/s40430-023-04175-0

A Finite Element Method approach is presented for the solution of the two-dimensional wave-diffusion equation. The fractional time derivative is considered as a Caputo derivative. Houbolt and Newmark methods are employed for the time-marching process... Read More about The solution of the wave-diffusion equation by a Caputo derivative-based Finite Element Method formulation.

An isogeometric boundary element formulation for stress concentration problems in couple stress elasticity (2023)
Journal Article
Hattori, G., Trevelyan, J., & Gourgiotis, P. (2023). An isogeometric boundary element formulation for stress concentration problems in couple stress elasticity. Computer Methods in Applied Mechanics and Engineering, 407, Article 115932. https://doi.org/10.1016/j.cma.2023.115932

An isogeometric boundary element method (IGABEM) is developed for the analysis of two-dimensional linear and isotropic elastic bodies governed by the couple stress theory. This theory is the simplest generalised continuum theory that can eectively mo... Read More about An isogeometric boundary element formulation for stress concentration problems in couple stress elasticity.

The solution of the anomalous diffusion equation by a Finite Element Method based on the Caputo derivative (2022)
Journal Article
Correa, R., Carrer, J., Solheid, B., & Trevelyan, J. (2022). The solution of the anomalous diffusion equation by a Finite Element Method based on the Caputo derivative. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 44(6), Article 250. https://doi.org/10.1007/s40430-022-03544-5

A Finite Element Method formulation is developed for the solution of the anomalous diffusion equation. This equation belongs to the branch of mathematics called fractional calculus; it is governed by a partial differential equation in which a fractio... Read More about The solution of the anomalous diffusion equation by a Finite Element Method based on the Caputo derivative.

An isogeometric boundary element method for heat transfer problems of multiscale structures in electronic packaging with arbitrary heat sources (2022)
Journal Article
Gong, Y., Chin, F., Dong, C., & Trevelyan, J. (2022). An isogeometric boundary element method for heat transfer problems of multiscale structures in electronic packaging with arbitrary heat sources. Applied Mathematical Modelling, 109, 161-185. https://doi.org/10.1016/j.apm.2022.03.047

We present an isogeometric boundary element method (IGABEM) capable of studying heat transfer problems for multiscale structures in electronic packaging problems. This method offers a number of key improvements compared with current analysis methods... Read More about An isogeometric boundary element method for heat transfer problems of multiscale structures in electronic packaging with arbitrary heat sources.

Analysis of 2D contact problems under cyclic loads using IGABEM with Bezier decomposition (2022)
Journal Article
Loyola, F., Doca, T., Campos, L., Trevelyan, J., & Albuquerque, E. (2022). Analysis of 2D contact problems under cyclic loads using IGABEM with Bezier decomposition. Engineering Analysis with Boundary Elements, 139, 246-263. https://doi.org/10.1016/j.enganabound.2022.03.017

Non-uniform rational B-splines (NURBS) are a convenient way to integrate CAD software and analysis codes, saving time from the operator and allowing efficient solution schemes that can be employed in the analysis of complex mechanical problems. In th... Read More about Analysis of 2D contact problems under cyclic loads using IGABEM with Bezier decomposition.

A NURBS-discontinuous and enriched isogeometric boundary element formulation for two-dimensional fatigue crack growth (2021)
Journal Article
Andrade, H., Trevelyan, J., & Leonel, E. (2022). A NURBS-discontinuous and enriched isogeometric boundary element formulation for two-dimensional fatigue crack growth. Engineering Analysis with Boundary Elements, 134, 259-281. https://doi.org/10.1016/j.enganabound.2021.09.019

A new extended isogeometric boundary element method (XIGABEM) formulation is proposed for simulating multiple fatigue crack propagation in two-dimensional domains. The classical use of NURBS in isogeometric formulations is further extended by repeate... Read More about A NURBS-discontinuous and enriched isogeometric boundary element formulation for two-dimensional fatigue crack growth.

Frequency domain Bernstein-Bezier finite element solver for modelling short waves in elastodynamics (2021)
Journal Article
Benatia, N., El Kacimi, A., Laghrouche, O., El Alaoui, M., & Trevelyan, J. (2022). Frequency domain Bernstein-Bezier finite element solver for modelling short waves in elastodynamics. Applied Mathematical Modelling, 102, 115-136. https://doi.org/10.1016/j.apm.2021.09.034

This work presents a high-order Bernstein-Bézier finite element (FE) discretisation to accurately solve time harmonic elastic wave problems on unstructured triangular mesh grids. Although high-order FEs possess many advantages over standard FEs, the... Read More about Frequency domain Bernstein-Bezier finite element solver for modelling short waves in elastodynamics.

A boundary element method formulation based on the Caputo derivative for the solution of the diffusion-wave equation (2021)
Journal Article
Carrer, J., Solheid, B., Trevelyan, J., & Seaid, M. (online). A boundary element method formulation based on the Caputo derivative for the solution of the diffusion-wave equation. Engineering with Computers, https://doi.org/10.1007/s00366-021-01480-x

A boundary element method formulation is developed and validated through the solution of problems governed by the diffusion-wave equation, for which the order of the time derivative, say α, ranges in the interval (1, 2). This fractional time derivati... Read More about A boundary element method formulation based on the Caputo derivative for the solution of the diffusion-wave equation.

A well simulator for homogeneous reservoirs based on formulations of the isogeometric boundary element method (2021)
Journal Article
Nascimento, L., Gontijo, G., Albuquerque, E., Campos, L., Trevelyan, J., & Fortaleza, E. (2021). A well simulator for homogeneous reservoirs based on formulations of the isogeometric boundary element method. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 43, Article 206. https://doi.org/10.1007/s40430-021-02924-7

The development of a simulator for homogeneous reservoirs with application in producer wells (represented by a sink) and the aquifer analysis is obtained by combining the Boundary Element Method (BEM), the Isogeometric Formulation using NURBS (Non Un... Read More about A well simulator for homogeneous reservoirs based on formulations of the isogeometric boundary element method.

Quadrature methods for highly oscillatory singular integrals (2020)
Journal Article
Gao, J., Condon, M., Iserles, A., Gilvey, B., & Trevelyan, J. (2021). Quadrature methods for highly oscillatory singular integrals. Journal of computational mathematics, 39(2), 227-260. https://doi.org/10.4208/jcm.1911-m2019-0044

We address the evaluation of highly oscillatory integrals, with power-law and logarithmic singularities. Such problems arise in numerical methods in engineering. Notably, the evaluation of oscillatory integrals dominates the run-time for wave-enriche... Read More about Quadrature methods for highly oscillatory singular integrals.

A comparison of high-order and plane wave enriched boundary element basis functions for Helmholtz problems (2020)
Journal Article
Gilvey, B., & Trevelyan, J. (2021). A comparison of high-order and plane wave enriched boundary element basis functions for Helmholtz problems. Engineering Analysis with Boundary Elements, 122, 190-201. https://doi.org/10.1016/j.enganabound.2020.10.008

When undertaking a numerical solution of Helmholtz problems using the Boundary Element Method (BEM) it is common to employ low-order Lagrange polynomials, or more recently Non-Uniform Rational B-Splines (NURBS), as basis functions. A popular alternat... Read More about A comparison of high-order and plane wave enriched boundary element basis functions for Helmholtz problems.

A boundary element method formulation based on the Caputo derivative for the solution of the anomalous diffusion problem (2020)
Journal Article
Carrer, J., Solheid, B., Trevelyan, J., & Seaid, M. (2021). A boundary element method formulation based on the Caputo derivative for the solution of the anomalous diffusion problem. Engineering Analysis with Boundary Elements, 122, 132-144. https://doi.org/10.1016/j.enganabound.2020.10.017

This work presents a boundary element method formulation for the solution of the anomalous diffusion problem. By keeping the fractional time derivative as it appears in the governing differential equation of the problem, and by employing a Weighted R... Read More about A boundary element method formulation based on the Caputo derivative for the solution of the anomalous diffusion problem.

Hybrid nearly singular integration for three-dimensional isogeometric boundary element analysis of coatings and other thin structures (2020)
Journal Article
Gong, Y., Dong, C., Qin, F., Hattori, G., & Trevelyan, J. (2020). Hybrid nearly singular integration for three-dimensional isogeometric boundary element analysis of coatings and other thin structures. Computer Methods in Applied Mechanics and Engineering, 367, Article 113099. https://doi.org/10.1016/j.cma.2020.113099

The isogeometric boundary element method (IGABEM) has great potential for the simulation of elasticity problems because of its exact geometric representation and good approximation properties. These advantages can be extended to thin structures, incl... Read More about Hybrid nearly singular integration for three-dimensional isogeometric boundary element analysis of coatings and other thin structures.

The Boundary Element Method applied to the solution of the Diffusion-Wave problem (2020)
Journal Article
Carrer, J., Solheid, B., Trevelyan, J., & Seaid, M. (2020). The Boundary Element Method applied to the solution of the Diffusion-Wave problem. Engineering Analysis with Boundary Elements, 117, 13-25. https://doi.org/10.1016/j.enganabound.2020.03.027

A Boundary Element Method formulation is developed for the solution of the two-dimensional diffusion-wave problem, which is governed by a partial differential equation presenting a time fractional derivative of order α, with 1.0 < α < 2.0. In the pro... Read More about The Boundary Element Method applied to the solution of the Diffusion-Wave problem.

Singular enrichment functions for Helmholtz scattering at corner locations using the Boundary Element Method (2019)
Journal Article
Gilvey, B., Trevelyan, J., & Hattori, G. (2020). Singular enrichment functions for Helmholtz scattering at corner locations using the Boundary Element Method. International Journal for Numerical Methods in Engineering, 121(3), 519-533. https://doi.org/10.1002/nme.6232

In this paper we use an enriched approximation space for the efficient and accurate solution of the Helmholtz equation in order to solve problems of wave scattering by polygonal obstacles. This is implemented in both Boundary Element Method (BEM) and... Read More about Singular enrichment functions for Helmholtz scattering at corner locations using the Boundary Element Method.

The Boundary Element Method Applied to the Solution of the Anomalous Diffusion Problem (2019)
Journal Article
Carrer, J., Seaid, M., Trevelyan, J., & Solheid, B. (2019). The Boundary Element Method Applied to the Solution of the Anomalous Diffusion Problem. Engineering Analysis with Boundary Elements, 109, 129-142. https://doi.org/10.1016/j.enganabound.2019.09.016

A Boundary Element Method formulation is developed for the solution of the two-dimensional anomalous diffusion equation. Initially, the Riemann–Liouville Fractional derivative is applied on both sides of the partial differential equation (PDE), thus... Read More about The Boundary Element Method Applied to the Solution of the Anomalous Diffusion Problem.

Enhanced Conformal Perfectly Matched Layers for Bernstein-Bezier Finite Element Modelling of Short Wave Scattering (2019)
Journal Article
El-Kacimi, A., Laghrouche, O., Ouazar, D., Mohamed, M., Seaid, M., & Trevelyan, J. (2019). Enhanced Conformal Perfectly Matched Layers for Bernstein-Bezier Finite Element Modelling of Short Wave Scattering. Computer Methods in Applied Mechanics and Engineering, 355, 614-638. https://doi.org/10.1016/j.cma.2019.06.032

The aim of this paper is to accurately solve short wave scattering problems governed by the Helmholtz equation using the Bernstein-Bezier Finite Element method (BBFEM), combined with a conformal perfectly matched layer (PML). Enhanced PMLs, where cur... Read More about Enhanced Conformal Perfectly Matched Layers for Bernstein-Bezier Finite Element Modelling of Short Wave Scattering.

Discontinuous isogeometric boundary element (IGABEM) formulations in 3D automotive acoustics (2019)
Journal Article
Sun, Y., Trevelyan, J., Hattori, G., & Lu, C. (2019). Discontinuous isogeometric boundary element (IGABEM) formulations in 3D automotive acoustics. Engineering Analysis with Boundary Elements, 105, 303-311. https://doi.org/10.1016/j.enganabound.2019.04.011

The isogeometric boundary element method (IGABEM) is a technique that employs non-uniform rational B-splines (NURBS) as basis functions to discretise the solution variables as well as the problem geometry in a boundary element formulation. IGABEM has... Read More about Discontinuous isogeometric boundary element (IGABEM) formulations in 3D automotive acoustics.

An adaptive SVD-Krylov reduced order model for surrogate based structural shape optimization through isogeometric boundary element method (2019)
Journal Article
Li, S., Trevelyan, J., Wu, Z., Lian, H., & Zhang, W. (2019). An adaptive SVD-Krylov reduced order model for surrogate based structural shape optimization through isogeometric boundary element method. Computer Methods in Applied Mechanics and Engineering, 349, 312-338. https://doi.org/10.1016/j.cma.2019.02.023

This work presents an adaptive Singular Value Decomposition (SVD)-Krylov reduced order model to solve structural optimization problems. By utilizing the SVD, it is shown that the solution space of a structural optimization problem can be decomposed i... Read More about An adaptive SVD-Krylov reduced order model for surrogate based structural shape optimization through isogeometric boundary element method.

A solution approach for contact problems based on the dual interpolation boundary face method (2019)
Journal Article
Zhang, J., Shu, X., Trevelyan, J., Lin, W., & Chai, P. (2019). A solution approach for contact problems based on the dual interpolation boundary face method. Applied Mathematical Modelling, 70, 643-658. https://doi.org/10.1016/j.apm.2019.02.013

The recently proposed dual interpolation boundary face method (DiBFM) has been shown to have a much higher accuracy and improved convergence rates compared with the traditional boundary element method. In addition, the DiBFM has the ability to approx... Read More about A solution approach for contact problems based on the dual interpolation boundary face method.

Hybrid nearly singular integration for isogeometric boundary element analysis of coatings and other thin 2D structures (2018)
Journal Article
Gong, Y., Trevelyan, J., Hattori, G., & Dong, C. (2019). Hybrid nearly singular integration for isogeometric boundary element analysis of coatings and other thin 2D structures. Computer Methods in Applied Mechanics and Engineering, 346, 642-673. https://doi.org/10.1016/j.cma.2018.12.019

We present an isogeometric boundary element method (IGABEM) capable of delivering accurate and efficient solutions in the heat transfer analysis of 2D coated structures such as those commonly found in turbomachinery. Although we consider very thin co... Read More about Hybrid nearly singular integration for isogeometric boundary element analysis of coatings and other thin 2D structures.

Bernstein - Bézier based finite elements for efficient solution of short wave problems (2018)
Journal Article
El Kacimi, A., Laghrouche, O., Mohamed, M., & Trevelyan, J. (2019). Bernstein - Bézier based finite elements for efficient solution of short wave problems. Computer Methods in Applied Mechanics and Engineering, 343, 166-185. https://doi.org/10.1016/j.cma.2018.07.040

In this work, the Bernstein-Bézier Finite Element Method (BBFEM) is implemented to solve short wave problems governed by the Helmholtz equation on unstructured triangular mesh grids. As for the hierarchical Finite Element (FE) approach, this high ord... Read More about Bernstein - Bézier based finite elements for efficient solution of short wave problems.

A non-ordinary state-based peridynamics framework for anisotropic materials (2018)
Journal Article
Hattori, G., Trevelyan, J., & Coombs, W. (2018). A non-ordinary state-based peridynamics framework for anisotropic materials. Computer Methods in Applied Mechanics and Engineering, 339, 416-442. https://doi.org/10.1016/j.cma.2018.05.007

Peridynamics (PD) represents a new approach for modelling fracture mechanics, where a continuum domain is modelled through particles connected via physical interactions. This formulation allows us to model crack initiation, propagation, branching and... Read More about A non-ordinary state-based peridynamics framework for anisotropic materials.

Accelerating isogeometric boundary element analysis for 3-dimensional elastostatics problems through black-box fast multipole method with proper generalized decomposition (2018)
Journal Article
Li, S., Trevelyan, J., Zhang, W., & Wang, D. (2018). Accelerating isogeometric boundary element analysis for 3-dimensional elastostatics problems through black-box fast multipole method with proper generalized decomposition. International Journal for Numerical Methods in Engineering, 114(9), 975-998. https://doi.org/10.1002/nme.5773

The isogeometric approach to computational engineering analysis makes use of Non-Uniform Rational B-splines (NURBS) to discretise both the geometry and the analysis field variables, giving a higher fidelity geometric description and leading to improv... Read More about Accelerating isogeometric boundary element analysis for 3-dimensional elastostatics problems through black-box fast multipole method with proper generalized decomposition.

Numerical Simulation of MZF Design with Non-planar Hydraulic Fracturing from Multi-lateral Horizontal Wells (2017)
Journal Article
Sobhaniaragh, B., Trevelyan, J., Mansur, W., & Peters, F. (2017). Numerical Simulation of MZF Design with Non-planar Hydraulic Fracturing from Multi-lateral Horizontal Wells. Journal of Natural Gas Science and Engineering, 46, 93-107. https://doi.org/10.1016/j.jngse.2017.07.005

In recent years, developments in the oil and gas industry have evolved significantly in advancing the mechanical systems technology to perform hydraulic fracturing. However, further developments will require an in-depth understanding of the impacts o... Read More about Numerical Simulation of MZF Design with Non-planar Hydraulic Fracturing from Multi-lateral Horizontal Wells.

High-order finite elements for the solution of Helmholtz problems (2017)
Journal Article
Christodoulou, K., Laghrouche, O., Mohamed, M., & Trevelyan, J. (2017). High-order finite elements for the solution of Helmholtz problems. Computers and Structures, 191, 129-139. https://doi.org/10.1016/j.compstruc.2017.06.010

In this paper, two high-order finite element models are investigated for the solution of two-dimensional wave problems governed by the Helmholtz equation. Plane wave enriched finite elements, developed in the Partition of Unity Finite Element Method... Read More about High-order finite elements for the solution of Helmholtz problems.

Implementation and computational aspects of a 3D elastic wave modelling by PUFEM (2017)
Journal Article
Mahmood, M., Laghrouche, O., Trevelyan, J., & El Kacimi, A. (2017). Implementation and computational aspects of a 3D elastic wave modelling by PUFEM. Applied Mathematical Modelling, 49, 568-586. https://doi.org/10.1016/j.apm.2017.05.013

This paper presents an enriched finite element model for three dimensional elastic wave problems, in the frequency domain, capable of containing many wavelengths per nodal spacing. This is achieved by applying the plane wave basis decomposition to th... Read More about Implementation and computational aspects of a 3D elastic wave modelling by PUFEM.

A boundary element and level set based bi-directional evolutionary structural optimisation with a volume constraint (2017)
Journal Article
Ullah, B., Trevelyan, J., & Islam, S. (2017). A boundary element and level set based bi-directional evolutionary structural optimisation with a volume constraint. Engineering Analysis with Boundary Elements, 80, 152-161. https://doi.org/10.1016/j.enganabound.2017.02.012

A new topology optimisation algorithm is implemented and presented for compliance minimisation of continuum structures using a volume preserving mechanism which effectively handles a volume constraint. The volume preserving mechanism is based on a un... Read More about A boundary element and level set based bi-directional evolutionary structural optimisation with a volume constraint.

Enriched finite elements for initial-value problem of transverse electromagnetic waves in time domain (2017)
Journal Article
Drolia, M., Mohamed, M., Laghrouche, O., Seaid, M., & Trevelyan, J. (2017). Enriched finite elements for initial-value problem of transverse electromagnetic waves in time domain. Computers and Structures, 182, 354-367. https://doi.org/10.1016/j.compstruc.2016.11.011

This paper proposes a partition of unity enrichment scheme for the solution of the electromagnetic wave equation in the time domain. A discretization scheme in time is implemented to render implicit solutions of systems of equations possible. The sch... Read More about Enriched finite elements for initial-value problem of transverse electromagnetic waves in time domain.

An extended boundary element method formulation for the direct calculation of the stress intensity factors in fully anisotropic materials (2016)
Journal Article
Hattori, G., Alatawi, I., & Trevelyan, J. (2017). An extended boundary element method formulation for the direct calculation of the stress intensity factors in fully anisotropic materials. International Journal for Numerical Methods in Engineering, 109(7), 965-981. https://doi.org/10.1002/nme.5311

We propose a formulation for linear elastic fracture mechanics (LEFM) in which the stress intensity factors (SIF) are found directly from the solution vector of an extended boundary element method (XBEM) formulation. The enrichment is embedded in the... Read More about An extended boundary element method formulation for the direct calculation of the stress intensity factors in fully anisotropic materials.

A boundary element and level set based topology optimisation using sensitivity analysis (2016)
Journal Article
Ullah, B., & Trevelyan, J. (2016). A boundary element and level set based topology optimisation using sensitivity analysis. Engineering Analysis with Boundary Elements, 70, 80-98. https://doi.org/10.1016/j.enganabound.2016.06.001

The structural topology optimisation method presented in this paper is based on the boundary element method, level set method and shape sensitivity analysis for two-dimensional linear elastic problems. The proposed method automatically nucleates hole... Read More about A boundary element and level set based topology optimisation using sensitivity analysis.

Backward waves with double zero-group-velocity points in a liquid-filled pipe (2016)
Journal Article
Cui, H., Lin, W., Zhang, H., Wang, X., & Trevelyan, J. (2016). Backward waves with double zero-group-velocity points in a liquid-filled pipe. The Journal of the Acoustical Society of America, 139(3), 1179-1194. https://doi.org/10.1121/1.4944046

Hollow cylinders often exhibit backward propagation modes whose group and phase velocities have opposite directions, and these exhibit a minimum possible frequency at which the group velocity vanishes at a nonzero wavenumber. These zero-group-velocit... Read More about Backward waves with double zero-group-velocity points in a liquid-filled pipe.

Numerical simulation of fracking in shale rocks: current state and future approaches (2016)
Journal Article
Hattori, G., Trevelyan, J., Augarde, C., Coombs, W., & Aplin, A. (2017). Numerical simulation of fracking in shale rocks: current state and future approaches. Archives of Computational Methods in Engineering, 24(2), 281-317. https://doi.org/10.1007/s11831-016-9169-0

Extracting gas from shale rocks is one of the current engineering challenges but offers the prospect of cheap gas. Part of the development of an effective engineering solution for shale gas extraction in the future will be the availability of reliabl... Read More about Numerical simulation of fracking in shale rocks: current state and future approaches.

A three-dimensional implementation of the boundary element and level set based structural optimisation (2015)
Journal Article
Ullah, B., Trevelyan, J., & Ivrissimtzis, I. (2015). A three-dimensional implementation of the boundary element and level set based structural optimisation. Engineering Analysis with Boundary Elements, 58, 176-194. https://doi.org/10.1016/j.enganabound.2015.04.005

This paper presents a three-dimensional structural optimisation approach based on the boundary element and level set methods. The structural geometry is implicitly represented with the level set method, which evolves an initial structural model towar... Read More about A three-dimensional implementation of the boundary element and level set based structural optimisation.

Interactive three-dimensional boundary element stress analysis of components in aircraft structures (2015)
Journal Article
Foster, T., Mohamed, M., Trevelyan, J., Coates, G., Spence, S., & Walker, S. (2015). Interactive three-dimensional boundary element stress analysis of components in aircraft structures. Engineering Analysis with Boundary Elements, 56, 190-200. https://doi.org/10.1016/j.enganabound.2015.01.017

Computer aided design of mechanical components is an iterative process that often involves multiple stress analysis runs; this can be time consuming and expensive. Significant efficiency improvements can be made by increasing interactivity at the con... Read More about Interactive three-dimensional boundary element stress analysis of components in aircraft structures.

A direct SIF approach for anisotropic materials using the boundary element method (2015)
Presentation / Conference Contribution
Hattori, G., Alatawi, I., & Trevelyan, J. (2015). A direct SIF approach for anisotropic materials using the boundary element method. In A. J. Gil, & R. Sevilla (Eds.), Proceedings of the 23rd Conference on Computational Mechanics, ACME-UK 2015, 8th-10th April 2015, College of Engineering, Swansea University, Wales, UK (279-282)

Recently developments in numerical methods such as the Extended Finite Element Method (X-FEM) and the Extended Boundary Element Method (X-BEM) have significantly improved the accuracy in linear elastic fracture mechanics (LEFM) problems. Nevertheless... Read More about A direct SIF approach for anisotropic materials using the boundary element method.

A direct evaluation of stress intensity factors using the Extended Dual Boundary Element Method (2015)
Journal Article
Alatawi, I., & Trevelyan, J. (2015). A direct evaluation of stress intensity factors using the Extended Dual Boundary Element Method. Engineering Analysis with Boundary Elements, 52, 56-63. https://doi.org/10.1016/j.enganabound.2014.11.022

We introduce an alternative method in computational fracture mechanics to evaluate Stress Intensity Factors (SIFs) directly using the Extended Dual Boundary Element Method (XBEM) for 2D problems. Like other enrichment approaches, the new approach is... Read More about A direct evaluation of stress intensity factors using the Extended Dual Boundary Element Method.

Extended isogeometric boundary element method (XIBEM) for three-dimensional medium-wave acoustic scattering problems (2015)
Journal Article
Peake, M., Trevelyan, J., & Coates, G. (2015). Extended isogeometric boundary element method (XIBEM) for three-dimensional medium-wave acoustic scattering problems. Computer Methods in Applied Mechanics and Engineering, 284, 762-780. https://doi.org/10.1016/j.cma.2014.10.039

A boundary element method (BEM), based on non-uniform rational B-splines (NURBS), is used to find solutions to three-dimensional wave scattering problems governed by the Helmholtz equation. The method is extended in a partition-of-unity sense, multip... Read More about Extended isogeometric boundary element method (XIBEM) for three-dimensional medium-wave acoustic scattering problems.

Mixed enrichment for the finite element method in heterogeneous media (2014)
Journal Article
Diwan, G., Mohamed, M., Seaid, M., Trevelyan, J., & Laghrouche, O. (2015). Mixed enrichment for the finite element method in heterogeneous media. International Journal for Numerical Methods in Engineering, 101(1), 54-78. https://doi.org/10.1002/nme.4795

Problems of multiple scales of interest or of locally nonsmooth solutions may often involve heterogeneous media. These problems are usually very demanding in terms of computations with the conventional finite element method. On the other hand, differ... Read More about Mixed enrichment for the finite element method in heterogeneous media.

Enriched BEM for fracture in anisotropic materials (2014)
Presentation / Conference Contribution
Hattori, G., Sáez, A., Trevelyan, J., & García-Sánchez, F. (2014). Enriched BEM for fracture in anisotropic materials. In V. Mallardo, & M. H. Aliabadi (Eds.), Advances in boundary element and meshless techniques XV (309-314)

Characteristics of group velocities of backward waves in a hollow cylinder (2014)
Journal Article
Cui, H., Lin, W., Zhang, H., Wang, X., & Trevelyan, J. (2014). Characteristics of group velocities of backward waves in a hollow cylinder. The Journal of the Acoustical Society of America, 135(6), 3398-3408. https://doi.org/10.1121/1.4872297

It is known that modes in axially uniform waveguides exhibit backward-propagation characteristics for which group and phase velocities have opposite signs. For elastic plates, group velocities of backward Lamb waves depend only on Poisson's ratio. Th... Read More about Characteristics of group velocities of backward waves in a hollow cylinder.

Boundary element simulation of fatigue crack growth in multi-site damage (2014)
Journal Article
Price, R., & Trevelyan, J. (2014). Boundary element simulation of fatigue crack growth in multi-site damage. Engineering Analysis with Boundary Elements, 43, 67-75. https://doi.org/10.1016/j.enganabound.2014.03.002

This paper presents an efficient and automatic scheme for modelling the growth of multiple cracks through a two-dimensional domain under fatigue loading based on linear elastic fracture mechanics. The dual boundary element method is applied to perfor... Read More about Boundary element simulation of fatigue crack growth in multi-site damage.

Dynamically-controlled variable-fidelity modelling for aircraft structural design optimisation (2014)
Journal Article
Allen, J., Coates, G., & Trevelyan, J. (2014). Dynamically-controlled variable-fidelity modelling for aircraft structural design optimisation. Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, 228(8), 1434-1449. https://doi.org/10.1177/0954410013493074

Structural mass optimisation of an aircraft design is important in increasing the likelihood that a high quality airframe is designed of minimal weight whilst providing necessary resistance to load. Analysis of such structures is often performed at a... Read More about Dynamically-controlled variable-fidelity modelling for aircraft structural design optimisation.

Structural optimisation based on the boundary element and level set methods (2014)
Journal Article
Ullah, B., Trevelyan, J., & Matthews, P. (2014). Structural optimisation based on the boundary element and level set methods. Computers and Structures, 137, 14-30. https://doi.org/10.1016/j.compstruc.2014.01.004

A new method of structural topology optimisation is proposed in which an evolutionary approach is used with boundary element and level set methods. During the optimisation iterations, the proposed method automatically introduces internal cavities and... Read More about Structural optimisation based on the boundary element and level set methods.

The equal spacing of N points on a sphere with application to partition-of-unity wave diffraction problems (2014)
Journal Article
Peake, M., Trevelyan, J., & Coates, G. (2014). The equal spacing of N points on a sphere with application to partition-of-unity wave diffraction problems. Engineering Analysis with Boundary Elements, 40, 114-122. https://doi.org/10.1016/j.enganabound.2013.11.020

This paper addresses applications involving the selection of a set of points on a sphere, in which the uniformity of spacing can be of importance in enhancing the computational performance and/or the accuracy of some simulation. For the authors, the... Read More about The equal spacing of N points on a sphere with application to partition-of-unity wave diffraction problems.

A comparison of techniques for overcoming non-uniqueness of boundary integral equations for the collocation partition of unity method in two dimensional acoustic scattering (2013)
Journal Article
Diwan, G., Trevelyan, J., & Coates, G. (2013). A comparison of techniques for overcoming non-uniqueness of boundary integral equations for the collocation partition of unity method in two dimensional acoustic scattering. International Journal for Numerical Methods in Engineering, 96(10), 645-664. https://doi.org/10.1002/nme.4583

The Partition of Unity Method has become an attractive approach for extending the allowable frequency range for wave simulations beyond that available using piecewise polynomial elements. The non-uniqueness of solution obtained from the conventional... Read More about A comparison of techniques for overcoming non-uniqueness of boundary integral equations for the collocation partition of unity method in two dimensional acoustic scattering.

An enriched finite element model with q-refinement for radiative boundary layers in glass cooling (2013)
Journal Article
Mohamed, M., Seaid, M., Trevelyan, J., & Laghrouche, O. (2014). An enriched finite element model with q-refinement for radiative boundary layers in glass cooling. Journal of Computational Physics, 258, 718-737. https://doi.org/10.1016/j.jcp.2013.11.005

Radiative cooling in glass manufacturing is simulated using the partition of unity finite element method. The governing equations consist of a semi-linear transient heat equation for the temperature field and a stationary simplified P1 approximation... Read More about An enriched finite element model with q-refinement for radiative boundary layers in glass cooling.

Correlation between hole insertion criteria in a boundary element and level set based topology optimisation method (2013)
Journal Article
Ullah, B., & Trevelyan, J. (2013). Correlation between hole insertion criteria in a boundary element and level set based topology optimisation method. Engineering Analysis with Boundary Elements, 37(11), 1457-1470. https://doi.org/10.1016/j.enganabound.2013.08.003

The research work presented in this paper is based on the correlation between two hole insertion criteria in a boundary element method (BEM) and level set method (LSM) based structural topology optimisation scheme for 2D elastic problems. The hole in... Read More about Correlation between hole insertion criteria in a boundary element and level set based topology optimisation method.

Time-independent hybrid enrichment for finite element solution of transient conduction–radiation in diffusive grey media (2013)
Journal Article
Mohamed, M., Seaid, M., Trevelyan, J., & Laghrouche, O. (2013). Time-independent hybrid enrichment for finite element solution of transient conduction–radiation in diffusive grey media. Journal of Computational Physics, 251, 81-101. https://doi.org/10.1016/j.jcp.2013.05.030

We investigate the effectiveness of the partition-of-unity finite element method for transient conduction–radiation problems in diffusive grey media. The governing equations consist of a semi-linear transient heat equation for the temperature field a... Read More about Time-independent hybrid enrichment for finite element solution of transient conduction–radiation in diffusive grey media.

A hyper-heuristic approach to aircraft structural design optimization (2013)
Journal Article
Allen, J., Coates, G., & Trevelyan, J. (2013). A hyper-heuristic approach to aircraft structural design optimization. Structural and Multidisciplinary Optimization, 48(4), 807-819. https://doi.org/10.1007/s00158-013-0928-3

The conceptual design of an aircraft is a challenging problem in which optimization can be of great importance to the quality of design generated. Mass optimization of the structural design of an aircraft aims to produce an airframe of minimal mass w... Read More about A hyper-heuristic approach to aircraft structural design optimization.

Improving wind turbine drivetrain bearing reliability through pre-misalignment (2013)
Journal Article
Whittle, M., Trevelyan, J., Shin, W., & Tavner, P. (2013). Improving wind turbine drivetrain bearing reliability through pre-misalignment. Wind Energy, 17(8), 1217-1230. https://doi.org/10.1002/we.1629

Improving the reliability of wind turbines (WT) is an essential component in the bid to minimize the cost of energy, especially for offshore wind because of the difficulties associated with access for maintenance. Numerous studies have shown that WT... Read More about Improving wind turbine drivetrain bearing reliability through pre-misalignment.

Extended isogeometric boundary element method (XIBEM) for two-dimensional Helmholtz problems (2013)
Journal Article
Peake, M., Trevelyan, J., & Coates, G. (2013). Extended isogeometric boundary element method (XIBEM) for two-dimensional Helmholtz problems. Computer Methods in Applied Mechanics and Engineering, 259, 93-102. https://doi.org/10.1016/j.cma.2013.03.016

Isogeometric analysis is a topic of considerable interest in the field of numerical analysis. The boundary element method (BEM) requires only the bounding surface of geometries to be described; this makes non-uniform rational B-splines (NURBS), which... Read More about Extended isogeometric boundary element method (XIBEM) for two-dimensional Helmholtz problems.

An Isogeometric Boundary Element Method for elastostatic analysis: 2D implementation aspects (2013)
Journal Article
Simpson, R., Bordas, S., Lian, H., & Trevelyan, J. (2013). An Isogeometric Boundary Element Method for elastostatic analysis: 2D implementation aspects. Computers and Structures, 118, 2-12. https://doi.org/10.1016/j.compstruc.2012.12.021

The concept of isogeometric analysis, whereby the parametric functions that are used to describe CAD geometry are also used to approximate the unknown fields in a numerical discretisation, has progressed rapidly in recent years. This paper advances t... Read More about An Isogeometric Boundary Element Method for elastostatic analysis: 2D implementation aspects.

A partition of unity FEM for time-dependent diffusion problems using multiple enrichment functions (2013)
Journal Article
Mohamed, M., Seaid, M., Trevelyan, J., & Laghrouche, O. (2013). A partition of unity FEM for time-dependent diffusion problems using multiple enrichment functions. International Journal for Numerical Methods in Engineering, 93(3), 245-265. https://doi.org/10.1002/nme.4383

An enriched partition of unity FEM is developed to solve time-dependent diffusion problems. In the present formulation, multiple exponential functions describing the spatial and temporal diffusion decay are embedded in the finite element approximatio... Read More about A partition of unity FEM for time-dependent diffusion problems using multiple enrichment functions.

Novel basis functions for the partition of unity boundary element method for Helmholtz problems (2012)
Journal Article
Peake, M., Trevelyan, J., & Coates, G. (2012). Novel basis functions for the partition of unity boundary element method for Helmholtz problems. International Journal for Numerical Methods in Engineering, 93(9), 905-918. https://doi.org/10.1002/nme.4411

The BEM is a popular technique for wave scattering problems given its inherent ability to deal with infinite domains. In the last decade, the partition of unity BEM, in which the approximation space is enriched with a linear combination of plane wave... Read More about Novel basis functions for the partition of unity boundary element method for Helmholtz problems.

Rapid re-meshing and re-solution of three-dimensional boundary element problems for interactive stress analysis (2012)
Journal Article
Foster, T., Mohamed, M., Trevelyan, J., & Coates, G. (2012). Rapid re-meshing and re-solution of three-dimensional boundary element problems for interactive stress analysis. Engineering Analysis with Boundary Elements, 36(9), 1331-1343. https://doi.org/10.1016/j.enganabound.2012.02.020

Structural design of mechanical components is an iterative process that involves multiple stress analysis runs; this can be time consuming and expensive. It is becoming increasingly possible to make significant improvements in the efficiency of this... Read More about Rapid re-meshing and re-solution of three-dimensional boundary element problems for interactive stress analysis.

Evaluation of J1 and J2 integrals for curved cracks using an enriched Boundary Element Method (2011)
Journal Article
Simpson, R., & Trevelyan, J. (2011). Evaluation of J1 and J2 integrals for curved cracks using an enriched Boundary Element Method. Engineering Fracture Mechanics, 78(4), 623-637. https://doi.org/10.1016/j.engfracmech.2010.12.006

This paper introduces an enriched Boundary Element Method in which functions are introduced that are known to model singularities or discontinuities from a priori knowledge of the solution space. Additional fundamental solutions are introduced to sol... Read More about Evaluation of J1 and J2 integrals for curved cracks using an enriched Boundary Element Method.

A partition of unity enriched dual boundary element method for accurate computations in fracture mechanics (2011)
Journal Article
Simpson, R., & Trevelyan, J. (2011). A partition of unity enriched dual boundary element method for accurate computations in fracture mechanics. Computer Methods in Applied Mechanics and Engineering, 200(1-4), 1-10. https://doi.org/10.1016/j.cma.2010.06.015

This paper introduces an enriched Boundary Element Method in which functions are introduced that are known to model singularities or discontinuities from a priori knowledge of the solution space. Additional fundamental solutions are introduced to sol... Read More about A partition of unity enriched dual boundary element method for accurate computations in fracture mechanics.

Numerical evaluation of two-dimensional partition of unity boundary integrals for Helmholtz problems. (2010)
Journal Article
Honnor, M., Trevelyan, J., & Huybrechs, D. (2010). Numerical evaluation of two-dimensional partition of unity boundary integrals for Helmholtz problems. Journal of Computational and Applied Mathematics, 234(6), 1656-1662. https://doi.org/10.1016/j.cam.2009.08.012

There has been considerable attention given in recent years to the problem of extending finite and boundary element-based analysis of Helmholtz problems to higher frequencies. One approach is the Partition of Unity Method, which has been applied succ... Read More about Numerical evaluation of two-dimensional partition of unity boundary integrals for Helmholtz problems..

A coupled BEM/Scaled Boundary FEM formulation for accurate computations in linear elastic fracture mechanics (2010)
Journal Article
Bird, G., Trevelyan, J., & Augarde, C. (2010). A coupled BEM/Scaled Boundary FEM formulation for accurate computations in linear elastic fracture mechanics. Engineering Analysis with Boundary Elements, 34(6), 599-610. https://doi.org/10.1016/j.enganabound.2010.01.007

Issues relating to the practical implementation of the coupled boundary element–scaled boundary finite element method are addressed in this paper. A detailed approach highlights fully the process of applying boundary conditions, including the treatme... Read More about A coupled BEM/Scaled Boundary FEM formulation for accurate computations in linear elastic fracture mechanics.

On adaptive definition of the plane wave basis for wave boundary elements in acoustic scattering: the 2D case (2010)
Journal Article
Trevelyan, J., & Coates, G. (2010). On adaptive definition of the plane wave basis for wave boundary elements in acoustic scattering: the 2D case. Computer Modeling in Engineering & Sciences, 55(2), 147-170. https://doi.org/10.3970/cmes.2010.055.147

The terminology "wave boundary elements" relates to boundary elements enriched in the Partition of Unity sense by a multiple plane wave basis for the analysis of the propagation of short wavelength waves. This paper presents a variant of this approac... Read More about On adaptive definition of the plane wave basis for wave boundary elements in acoustic scattering: the 2D case.

A numerical coordinate transformation for efficient evaluation of oscillatory integrals over wave boundary elements. (2009)
Journal Article
Trevelyan, J., & Honnor, M. (2009). A numerical coordinate transformation for efficient evaluation of oscillatory integrals over wave boundary elements. The Journal of integral equations and applications, 21(3), 447-468. https://doi.org/10.1216/jie-2009-21-3-447

When the Partition of Unity Method is applied to a discretised integral equation form of the Helmholtz operator, the computational cost is dominated by the evaluation of highly oscillatory integrals over discretisations. This paper presents a new num... Read More about A numerical coordinate transformation for efficient evaluation of oscillatory integrals over wave boundary elements..

Efficient Calculation of Stress Intensity Factors using a Coupled BEM-SBFEM Algorithm. (2008)
Presentation / Conference Contribution
Bird, G. E., Trevelyan, J., & Augarde, C. E. (2008). Efficient Calculation of Stress Intensity Factors using a Coupled BEM-SBFEM Algorithm. In B. A. Schrefler, & U. Perego (Eds.), 8th World Congress on Computational Mechanics WCCM8. 5th European Congress on Computational Methods in Applied Sciences and Engineering ECCOMAS 2008

On wave boundary elements for radiation and scattering problems with piecewise constant impedance (2005)
Journal Article
Perrey-Debain, E., Trevelyan, J., & Bettess, P. (2005). On wave boundary elements for radiation and scattering problems with piecewise constant impedance. IEEE Transactions on Antennas and Propagation, 53(2), 876-879. https://doi.org/10.1109/tap.2004.841274

Discrete methods of numerical analysis have been used successfully for decades for the solution of problems involving wave diffraction, etc. However, these methods, including the finite element and boundary element methods, can require a prohibitivel... Read More about On wave boundary elements for radiation and scattering problems with piecewise constant impedance.

Plane-wave basis finite elements and boundary elements for three-dimensional wave scattering (2004)
Journal Article
Perrey-Debain, E., Laghrouche, O., Bettess, P., & Trevelyan, J. (2004). Plane-wave basis finite elements and boundary elements for three-dimensional wave scattering. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 362(1816), 561-577. https://doi.org/10.1098/rsta.2003.1335

Classical finite-element and boundary-element formulations for the Helmholtz equation are presented, and their limitations with respect to the number of variables needed to model a wavelength are explained. A new type of approximation for the potenti... Read More about Plane-wave basis finite elements and boundary elements for three-dimensional wave scattering.

Wave boundary elements : a theoretical overview presenting applications in scattering of short waves (2004)
Journal Article
Perrey-Debain, E., Trevelyan, J., & Bettess, P. (2004). Wave boundary elements : a theoretical overview presenting applications in scattering of short waves. Engineering Analysis with Boundary Elements, 28(2), 131-141. https://doi.org/10.1016/s0955-7997%2803%2900127-9

It is well known that the use of conventional discrete numerical methods of analysis (FEM and BEM) in the solution of Helmholtz and elastodynamic wave problems is limited by an upper bound on frequency. The current work addresses this problem by inco... Read More about Wave boundary elements : a theoretical overview presenting applications in scattering of short waves.

Plane wave interpolation in direct collocation boundary element method for radiation and wave scattering : numerical aspects and applications (2003)
Journal Article
Perrey-Debain, E., Trevelyan, J., & Bettess, P. (2003). Plane wave interpolation in direct collocation boundary element method for radiation and wave scattering : numerical aspects and applications. Journal of Sound and Vibration, 261(5), 839-858. https://doi.org/10.1016/s0022-460x%2802%2901006-4

The classical boundary element formulation for the Helmholtz equation is rehearsed, and its limitations with respect to the number of variables needed to model a wavelength are explained. A new type of interpolation for the potential is then describe... Read More about Plane wave interpolation in direct collocation boundary element method for radiation and wave scattering : numerical aspects and applications.