Contents
List of Figures
List of Tables
1 Introduction of the equations of fluid dynamics
1.1 Presentation of the Euler equations
1.1.1 The Euler equations in differential form (vectors)
1.1.2 The Euler equations in differential form (components)
1.1.3 The solution of the Euler equations
1.1.4 The prototype numerical solution of the Euler equations
1.2 Derivation of the Euler equations
1.2.1 Possible basic quantities
1.2.2 Choice of basic quantities
1.2.3 Fluxes through surface
1.2.4 Changes of the conserved quantities
1.2.5 Euler equations in integral form
1.2.6 Euler equations: from integral to differential form I
1.2.7 Euler equations: from integral to differential form II
1.3 Extensions of the Euler equations
1.3.1 Hydrodynamics equations including viscosity
1.3.2 Hydrodynamics equations including gravity
1.3.3 Hydrodynamics equations including magnetic fields
1.3.4 Hydrodynamics equations including radiation
1.4 Radiation hydrodynamics of stellar atmospheres
1.4.1 Conditions in stellar atmospheres
1.4.2 Stationary case: assumptions
1.4.3 Stationary case: results
1.4.4 Static case
1.4.5 Coupling of radiation transport and hydrodynamics
1.5 Euler equations as hyperbolic system
1.5.1 1D Euler equations in conservation form
1.5.2 Quasi-linear system
1.5.3 Hyperbolic system
1.5.4 Eigenvalues for the Euler equations
2 The one-dimensional linear advection equation
2.1 Introduction of the linear advection equation
2.1.1 Linear advection as special case: density and momentum
2.1.2 Linear advection as special case: total energy
2.1.3 Linear advection as special case
2.1.4 Analytic solution of the linear advection equation
2.1.5 Solution along characteristic curves
2.2 Naive numerics: discretization attempts
2.2.1 Simple ODE: discretization
2.2.2 Simple ODE: examples
2.2.3 Simple ODE: remarks
2.2.4 Parabolic PDE: heat equation
2.2.5 Parabolic PDE: discretization
2.2.6 Parabolic PDE: stability
2.2.7 Parabolic PDE: example
2.2.8 Linear advection equation: discretization
2.2.9 Linear advection equation: crash
2.2.10 Linear advection equation: the lesson
2.3 Basic concepts
2.3.1 Discretization in space: wishlist
2.3.2 Discretization in space by finite differences
2.3.3 Discretization in space by finite volumes
2.3.4 Discretization in space by other methods
2.3.5 Discretization in space: grids
2.3.6 Integral form and weak solution
2.3.7 Integral form and flux centering
2.3.8 Centering of quantities, fluxes, and differences
2.3.9 Update formula in conservation form
2.3.10 Stencil diagrams
2.3.11 Stencil diagrams: spatial centering
2.3.12 Stencil diagrams: centering in time
2.3.13 CFL condition
2.3.14 Truncation error
2.3.15 Consistency - stability - convergence
2.3.16 Derivations of donor cell scheme
2.3.17 Further concepts
2.4 Examples
2.4.1 Parameter of the following examples
2.4.2 Naive FTCS scheme
2.4.3 Implicit centered scheme
2.4.4 BTCS scheme
2.4.5 Donor cell (FTBS) scheme
2.4.6 FTFS scheme
2.4.7 Lax-Friedrichs scheme
2.4.8 Lax-Wendroff scheme
2.4.9 Beam-Warming scheme
2.4.10 Fromm scheme
2.5 Analysis of schemes
2.5.1 Overshoot
2.5.2 Artificial viscosity
2.5.3 Modified equation for the FTFS scheme I
2.5.4 Modified equation for the FTFS scheme II
2.5.5 Modified equation for the FTBS scheme
2.5.6 Linear stability analysis of original PDE
2.5.7 Linear stability analysis: use
2.5.8 Linear stability analysis of naive FTCS scheme
2.5.9 Linear stability analysis of donor cell (FTBS) scheme
2.5.10 Linear stability analysis: remarks
2.6 Non-linear schemes
2.6.1 Godunov's idea
2.6.2 Monotonicity
2.6.3 Flux of PLM schemes
2.6.4 Examples: PLM: slopes with linear parameter dependence
2.6.5 PLM: slope-limiter
2.6.6 PLM scheme with Minmod slope-limiter
2.6.7 PLM scheme with vanLeer slope-limiter
2.6.8 PLM scheme with Superbee slope-limiter
2.6.9 PPM scheme
2.6.10 WENO scheme
2.6.11 Scheme with Superbee slope, only boundary value used
2.6.12 Further improvements
3 Non-linear advection: Burgers' equation
3.1 Introduction of Burgers' equation
3.1.1 Viscous and inviscid Burgers' equation
3.1.2 Solution along characteristic curves
3.1.3 Compression waves and shocks
3.1.4 Shock speed I
3.1.5 Shock speed II
3.1.6 Expansion waves
3.1.7 Similarity solutions I
3.1.8 Similarity solutions II
3.1.9 Classification of Riemann problems
3.2 Numerical examples
3.2.1 Velocity at cell boundary
3.2.2 Flux-splitting
3.2.3 Example: small-amplitude wave
3.2.4 Example: Gaussian and conservativity
3.2.5 Lax-Wendroff theorem
3.2.6 Example: step-function and conservativity
3.2.7 Example: expansion shock and rarefaction fan
3.2.8 Entropy production by artificial viscosity
3.2.9 Entropy fix
3.2.10 Concepts from the linear world
3.2.11 Transformation of shock speed formula
3.2.12 Second-order extension of flux formula
4 One-dimensional non-linear hydrodynamics
4.1 New Difficulties
4.1.1 A coupled non-linear system
4.1.2 Positivity of density
4.1.3 Positivity of pressure
4.1.4 Where is upwind?
4.2 The Riemann problem for the 1D Euler equations
4.2.1 The Riemann problem
4.2.2 Rankine-Hugoniot conditions
4.2.3 Example: Sod shock tube
4.2.4 Jumps in the solution of the Sod shock tube problem
4.3 Riemann solvers
4.3.1 Godunov-type schemes
4.3.2 Riemann solvers and higher-order schemes
4.4 Approximate (linear) Riemann solvers
4.4.1 Linearized flux
4.4.2 Linearized Riemann solver
4.4.3 Examples of schemes
4.4.4 Example: Sod shock tube with Roe solver, constant
4.4.5 Example: Sod shock tube with Roe solver, Minmod slope
4.4.6 Example: Sod shock tube with Roe solver, vanLeer slope
4.4.7 Example: Sod shock tube with Roe solver, Superbee slope
4.4.8 Example: Sod shock tube with Roe solver, PP reconstruction
4.5 Alternative concepts
5 Applications
5.1 Composing operators
5.1.1 Operator adding versus splitting
5.1.2 Godunov versus Strang operator splitting
5.1.3 Steady-state solutions with operator adding or splitting
5.1.4 Linear stability of operator adding or splitting
5.1.5 Going multi-dimensional
5.2 Coupling of hydrodynamics and radiation transport
5.2.1 Coupling
5.2.2 Stability requirements
5.2.3 Approximations
5.3 Improvements
5.3.1 Non-Cartesian and/or refined grids
5.3.2 Optimization strategies
A. Nomenclature
A..1 Quantities
A..2 Vector notation
B. Exercises
B..1 Linear advection
B..2 Expanding SN bubble hits molecular cloud
C. Schedule
D. References
D..1 Lecture Notes
D..2 Books
D..3 Articles
D..4 Hydrodynamic codes
Index