simulation as the third pillar in engineering ...xfem used for traction-free interface in wake of...
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JUBILEE SCIENTIFIC CONFERENCE “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
SIMULATION AS THE THIRD PILLAR IN ENGINEERING SCIENCE
RENÉ DE BORST REGIUS PROFESSOR OF CIVIL ENGINEERING AND
MECHANICS, UNIVERSITY OF GLASGOW
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
The Ancient Greeks: Plato vs Aristotle
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
• Plato: deductive reasoning is the basic mode for scientific progress
• Aristotle: induction is the cornerstone of progress in the sciences
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
From René Descartes and Sir Francis Bacon to the mid – 20th Century
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
• René Descartes (1596 – 1650) was a mathematician and further developed the method of deduction: Based on an idea (a hypothesis), one developed conclusions by systematic reasoning.
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
From René Descartes and Sir Francis Bacon to the mid – 20th Century
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
• Sir Francis Bacon (1561 – 1626), the father of empiricism, and further developed the method of induction: Based on one or more observation, one could develop a theory.
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
From René Descartes and Sir Francis Bacon to the mid – 20th Century
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
• Induction and deduction became the two pillars of modern science, including engineering science.
• Free translation:
Induction = Experiment
Deduction = Theory
THEORY EXPERIMENT
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
From René Descartes and Sir Francis Bacon to the mid – 20th Century
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
• In engineering and most natural sciences, the theory is often described in terms of partial differential equations.
• Analysis is needed to solve these…
THEORY EXPERIMENT
ANALYSIS
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
From René Descartes and Sir Francis Bacon to the mid – 20th Century
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
• For complicated geometries, non-linear effects etc. analysis tools are not powerful enough.
• This is how SIMULATION
entered as the third pillar
THEORY EXPERIMENT
SIMULATION
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
The Modern Age: Some Possibilities
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
• All simulation relies on discretisation: replacing partial differential equations by discrete (algebraic) equations.
Examples:
Finite difference methods
Boundary integral methods
Finite element methods
Meshless methods, IsoGeometric Analysis, …
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
The Modern Age: Some Possibilities
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
It is enabled by the development of
modern, digital computers. Application areas:
Structural engineering
Safety: crash simulation
Optimisation
Electro-magnetics and wave guides
Patient-specific simulations
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Structural Engineering: Historical buildings
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
Courtesy: Jan Rots
St. Lambertus church
in Maastricht
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Safety: Crash Simulations
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
Courtesy: TASS Roll-over of a car
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Optimisation: Mega-Structures
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
Courtesy: Ole Sigmund Airbus A-380
? ?
Topology optimisation
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Optimisation: Nano-Optics
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
Courtesy: Ole Sigmund
Modelling of photonic
materials and wave guides
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Patient-specific simulations
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
Courtesy: Tom Hughes
Simulation of blood flow
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
• Starter notch at the left
• Red denotes MD space
• Thick drawn lines denote
finite elements with overlap
coupling
Combined MD – FEM calculations: overlap coupling with weight functions weak enforcement of velocity coupling in intermediate space XFEM used for traction-free interface in wake of crack tip
Dynamic crack propagation
And There is More: Discrete Simulation of Discrete Matter
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Increasing loading rate
1 - propagation 2,3 - shear zones 4,5 - branching
Continuum – atomistic coupling
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
And There is More: Discrete Simulation of Discrete Matter
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
• Multi-scale analyses
• Analyses for more physical phenomena
The paradigms of contemporary computational science
Example:
Simulation of existing and propagating
cracks in fluid-saturated porous medium
With applications to energy, environment, and health
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Multi-scale approach
Problem statement
Mass and momentum
balance on subgrid scale
Structured or unstructured
finite element discretisation
Crack propagation unbiased by finite element discretisation
Computational science now: Multi-Scale and Multi-Physics
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Linear-elastic fracture mechanics
Pressure gradient
Example calculations
Stationary cracks in a
fluid-saturated medium
Computational science now: Multi-Scale and Multi-Physics
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
pressure
Example calculations
Quasi-static loading
Biaxial test with initial
imperfection under axial
compression
Tresca-like criterion for
inception of shear band
Computational science now: Multi-Scale and Multi-Physics
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Isogeometric analysis of fracture
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
IsoGeometric Analysis: Another New Paradigm?
Isogeometric analysis: use spline functions for interpolation instead of Lagrange polynomials
splines
polynomials
Major advantage:
More accurate stress calculation
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Isogeometric analysis of fracture
Better flow calculation in porous media
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
IsoGeometric Analysis: Another New Paradigm?
Satisfaction of local mass balance
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Different orders of interpolation for the displacement and
the pressure in isogeometric analysis?
Cubic interpolastion for displacements
Quadratic interpolation for pressure
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
IsoGeometric Analysis: Another New Paradigm?
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Isogeometric analysis of porous media
The influence of the presence and direction of
cracks on the flow pattern in porous media
norm of displacements
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
IsoGeometric Analysis: Another New Paradigm?
Fluid velocity in cracks is several orders of magnitude higher than in porous medium
“PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”
Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science
• Simulation technology has a huge impact
on many aspects of our lives: safety,
energy, water & environment, health
• In the past fifty years it has evolved into the
Third Pillar of Science & Engineering,
indispensible for any novel development
• Yet, the awareness that it is a field of its
own, needing an evolution as such, is not
yet always there (politicians, funding
agencies, university administrators,…)
In sum…