PHY 688: Topics in Astrophysics: The Application of Simulation in Astrophysics
Syllabus
The following topics will be covered. Some will occupy more than one lecture. Lecture notes will be posted here after each class.
- Introduction and application of simulation to astrophysics
A brief overview of the areas where simulation is used in astrophysics
- Broad overview of conservation laws (LeVeque Ch. 2)
An introduction to the types of problems we will consider
- Derivation of the Euler equations (LeVeque Ch. 2, 14; Shu Ch. 2-4; Tritton Ch. 5)
A physically motivated derivation of the equations of hydrodynamics
- Instabilities and Turbulence (Shu Ch. 8,9; Shore Ch. 9)
A survey of the dominant instabilities in astrophysics
- A first look at shocks (Choudhuri Ch. 6)
A high-level discussion of wave steepening and the derivation of the Rankine-Hugoniot jump conditions
- Numerical differentiation and Errors (Laney Ch. 6)
A review of numerical differentiation, error norms, truncation error, and roundoff error
- ODEs
A brief review of solving ordinary differential equations numerically
- Finite-volume methods
more on the framework for solving hyperbolic PDEs
- Basics of Numerical Solutions (Ferziger & Peric Ch. 2)
An overview of the properties that make up a good solution method
- Linear advection equation
First order methods for solving a simple hyperbolic PDE.
- Explicit and implicit discretizations; stability analysis
derivation of the CFL condition
- Higher-order methods
Higher order reconstruction and slope limiters
- The Characteristic Form of the Euler Equations and Basics of Hyperbolic PDEs (Laney Ch. 3)
- Riemann problem
The Riemann problem for the Euler equations and approximate solutions
- Solving the Euler equations
Numerical methods for the equations of gas dynamics
- Case study: Type Ia supernovae
A discussion of simulation techniques used in the study of SNe Ia
- Multidimensions
Techniques for extending these methods to multiple dimensions
- Verification and validation
How to know if you are getting the right solution.
- Software development practices
Some tips and tools to help avoid common development mistakes
- Design of a hydro program
An overview of the design of a modern hydrodynamics code
- High-performance computing
Summary of the techniques used in high-performance computing, including MPI
- The FLASH code
Tutorial on using the FLASH hydrodynamics code
Some optional topics that will be covered if there is time:
- Numerical Methods for the Heat Equation
A brief discussion of some techniques used in solving the heat equation
- Multigrid
The multigrid method for solving elliptic PDEs
- PPM
An overview of the piecewise parabolic method
- Stellar Equation of State
Extending methods to general equations of state
- Combustion
Techniques used in combustion
- AMR
An overview of adaptive mesh refinement
- Low speed flows
Methods for low Mach number flows in astrophysics
- Cosmological hydrodynamics
An introduction to the techniques used for cosmological simulation
Course work
There will be ~4 homework assigments throughout the term. Each
student will give a ~15-20 minute presentation on the application of
simulation to their field of interest. Additionally, these will be a
final computational project, involving setting up, running, and
analysing a fluid dynamics problem. Students will prepare a paper
describing their results. The topic will be chosen together with the
instructor.
updated Jan. 23, 2006