1,721,039 research outputs found
A novel single domain approach for numerical modelling Solid Oxide Fuel Cells
No full textPurpose – The purpose of this paper is to describe two- and three-dimensional numerical modelling
of solid oxide fuel cells (SOFCs) by employing an accurate and stable fully matrix inversion free finite
element algorithm.
Design/methodology/approach – A general and detailed mathematical model has been developed
for the description of the coupled complex phenomena occurring in fuel cells. A fully matrix inversion
free algorithm, based on the artificial compressibility (AC) version of the characteristic-based split
(CBS) scheme and single domain approach have been successfully employed for the accurate and
efficient simulation of high temperature SOFCs.
Findings – For the first time, a stable fully explicit algorithm has been applied to detailed multidimensional
simulation transport phenomena, coupled to chemical and electrochemical reactions, in
fluid, porous and solid parts of a SOFC. The accuracy of the present results has been verified via
comparison with experimental and numerical data available in the literature.
Originality/value – For the first time, thanks to a stabilization analysis conducted, the AC-CBS
algorithm has been successfully used to numerically solve the generalized model, applied in this
paper to describe transport phenomena through free fluid channels and porous electrodes of SOFCs,
without the need of further conditions at the fluid-electrode interface
Artificial Compressibility Based CBS Scheme for the Solution of the Generalized Porous Medium Model
No full textIn this work, the authors present an artificial compressibility (AC) version of the characteristic-
based split (CBS) algorithm for the numerical solution of flow through a fluidsaturated
porous medium. In this study, a fully matrix-inversion-free version of the CBS
algorithm is used for the first time to solve the generalized porous medium flow equations
for forced-, free-, and mixed-convection problems. The efficiency, the accuracy, and the
steady-state convergence of the AC-CBS algorithm are verified through comparison with
numerical and analytical solutions available in the literature. The advantages of the proposed
AC-CBS scheme include easy parallelization and implementation procedure
Laminar and turbulent flow calculations through a model human upper airway using unstructured meshes
No full textCharacteristic-based-split (CBS) algorithm for incompressible flow problems with heat transfer
No full textA physics-driven and machine learning-based digital twinning approach to transient thermal systems
No full textPurpose – In this study, the authors propose a novel digital twinning approach specifically designed
for controlling transient thermal systems. The purpose of this study is to harness the combined power of
deep learning (DL) and physics-based methods (PBM) to create an active virtual replica of the physical
system.
Design/methodology/approach – To achieve this goal, we introduce a deep neural network (DNN)
as the digital twin and a Finite Element (FE) model as the physical system. This integrated approach is
used to address the challenges of controlling an unsteady heat transfer problem with an integrated
feedback loop.
Findings – The results of our study demonstrate the effectiveness of the proposed digital twinning
approach in regulating the maximum temperature within the system under varying and unsteady heat flux
conditions. The DNN, trained on stationary data, plays a crucial role in determining the heat transfer
coefficients necessary to maintain temperatures below a defined threshold value, such as the material’s
melting point. The system is successfully controlled in 1D, 2D and 3D case studies. However, careful
evaluations should be conducted if such a training approach, based on steady-state data, is applied to
completely different transient heat transfer problems.
Originality/value – The present work represents one of the first examples of a comprehensive digital
twinning approach to transient thermal systems, driven by data. One of the noteworthy features of this
approach is its robustness. Adopting a training based on dimensionless data, the approach can
seamlessly accommodate changes in thermal capacity and thermal conductivity without the need for
retraining
Natural convection in porous medium-fluid interface problems: A finite element analysis by using the CBS procedure
No full textForced convection heat transfer from solder balls on a printed circuit board using the characteristic based split (CBS) scheme
No full textA stabilized finite element algorithm for the solution of SOFC problems
No full textIn this work, a new stabilized finite element algorithm, using a single domain approach for the solution of mass and energy transport phenomena in solid oxide fuel cells is presented. The proposed numerical procedure is based on the Artificial Compressibility (AC) Characteristic Based Split (CBS) scheme. The stability analysis carried out by the authors for the first time is based on the order of magnitude analysis of all the terms present in the conservation equations. The stability limits speed up the simulation process enormously. Furthermore, the single domain approach allows the application of the present method to the simulation of a whole cells stack
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