SIMULATION AS THE THIRD PILLAR IN ENGINEERING SCIENCE REN DE BORST - PowerPoint PPT Presentation

SIMULATION AS THE THIRD PILLAR IN ENGINEERING SCIENCE RENÉ DE BORST REGIUS PROFESSOR OF CIVIL ENGINEERING AND MECHANICS, UNIVERSITY OF GLASGOW JUBILEE SCIENTIFIC CONFERENCE “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

The Ancient Greeks: Plato vs Aristotle • Plato: deductive reasoning is the basic mode for scientific progress • Aristotle: induction is the cornerstone of progress in the sciences Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

From René Descartes and Sir Francis Bacon to the mid – 20th Century • 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. Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

From René Descartes and Sir Francis Bacon to the mid – 20th Century • 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. Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

From René Descartes and Sir Francis Bacon to the mid – 20th Century • Induction and deduction became the two pillars of modern science, including engineering science. • Free translation: THEORY EXPERIMENT Induction = Experiment Deduction = Theory Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

From René Descartes and Sir Francis Bacon to the mid – 20th Century • In engineering and most natural sciences, the theory is often described in terms of partial differential EXPERIMENT THEORY equations. • Analysis is needed to solve these… ANALYSIS Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

From René Descartes and Sir Francis Bacon to the mid – 20th Century • For complicated geometries, non-linear effects etc. analysis tools are not powerful enough. EXPERIMENT THEORY • This is how SIMULATION entered as the third pillar SIMULATION Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

The Modern Age: Some Possibilities • 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, … Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

The Modern Age: Some Possibilities 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 Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

Structural Engineering: Historical buildings St. Lambertus church in Maastricht Courtesy: Jan Rots Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

Safety: Crash Simulations Roll-over of a car Courtesy: TASS Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

Optimisation: Mega-Structures Topology optimisation ? ? Airbus A-380 Courtesy: Ole Sigmund Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

Optimisation: Nano-Optics Modelling of photonic materials and wave guides Courtesy: Ole Sigmund Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

Patient-specific simulations Simulation of blood flow Courtesy: Tom Hughes Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

And There is More: Discrete Simulation of Discrete Matter Dynamic crack propagation • 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 Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

And There is More: Continuum – atomistic coupling Discrete Simulation of Discrete Matter Increasing loading rate 1 - propagation 2,3 - shear zones 4,5 - branching Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

The paradigms of contemporary computational science • Multi-scale analyses • Analyses for more physical phenomena Example: Simulation of existing and propagating cracks in fluid-saturated porous medium With applications to energy, environment, and health Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

Computational science now: Problem statement Multi-Scale and Multi-Physics Crack propagation unbiased by Multi-scale approach finite element discreti sation Structured or unstructured Mass and momentum finite element discretisation balance on subgrid scale Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

Computational science now: Example calculations Multi-Scale and Multi-Physics Stationary cracks in a fluid-saturated medium Linear-elastic fracture mechanics Pressure gradient Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

Computational science now: Example calculations Multi-Scale and Multi-Physics Quasi-static loadi ng Biaxial test with initial imperfection under axial compression Tresca-like criterion for inception of shear band pressure 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: Isogeometric analysis of fracture Another New Paradigm? Isogeometric analysis: use spline functions for interpolation instead of Lagrange polynomials splines Major advantage: More accurate stress calculation polynomials 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: Isogeometric analysis of fracture Another New Paradigm? Better flow calculation in porous media Satisfaction of local mass balance 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: Another New Paradigm? 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 “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”

IsoGeometric Analysis: Isogeometric analysis of porous media Another New Paradigm? The influence of the presence and direction of cracks on the flow pattern in porous media norm of displacements Fluid velocity in cracks is several orders of magnitude higher than in porous medium Prof.dr.ir. René de Borst: Simulation as the Third Pillar in Engineering Science “PRACTICAL APPLICATIONS OF INNOVATIVE SOLUTIONS RESULTING FROM SCIENTIFIC RESEARCH”